Text Amendment - Residential Freestanding Solar Arrays_1st Reading Copyright 2014
City of Dubuque Public Hearings # 3.
ITEM TITLE: Text Amendment - Residential Freestanding Solar Arrays
SUMMARY: Proof of publication on notice of public hearing to consider a request by the
City of Dubuque to amend the Unified Development Code to establish
procedures for the review of new freestanding solar arrays and the Zoning
Advisory Commission recommending approval.
ORDINANCE Amending Title 16 of the City of Dubuque Code of
Ordinances, Unified Development Code, by Amending Articles 16-5-2-2
(R-1), 16-5-3-2 (R-2) 16-5-4.3 (R-2A), 16-5-5.3 (R-3) and 16-5-6.3 (R-4),
16-5-7.3 (OR) and 16-5-9.3 (OC) to establish maximum area and height
requirements for residential freestanding solar arrays
SUGGESTED DISPOSITION: Suggested Disposition: Receive and File; Motion B; Motion A
ATTACHMENTS:
Description Type
❑ ZAC Letter Staff Memo
❑ Staff Materials Supporting Documentation
❑ Staff Materials Supporting Documentation
❑ Ordinance Ordinance
❑ Public Input 1 Supporting Documentation
❑ Public Input 2 Supporting Documentation
❑ Public Input 3 Supporting Documentation
❑ Public input 4 Supporting Documentation
❑ Public Input 5 Supporting Documentation
❑ Public input 6 Supporting Documentation
❑ Public Input 7 Supporting Documentation
❑ Public Input 8 Supporting Documentation
❑ Public Input 9 Supporting Documentation
❑ Public Input 10 Supporting Documentation
❑ Public Input 11 Supporting Documentation
❑ Proof of Publication Supporting Documentation
❑ Suggested Motion Supporting Documentation
Planning Services Department Dubuque
City Hall THE CITY OF
50 West 13H,I Sheet 1 D TR E
Dubuque, A 52001-4864 lJ L
(563)589-4210 phone 11..
(563)5894221 fax •ma•mll Masterpiece on the Mississippi
(563)690-6678 TDD
planning@cityofdubuque.org
July 10, 2015
The Honorable Mayor and City Council Members
City of Dubuque
City Hall —50 W. 13th Street
DubuquelA 52001
Applicant: City of Dubuque
Description: Text Amendment regulating the size of Residential Freestanding Solar
Arrays
Dear Mayor and City Council Members:
The City of Dubuque Zoning Advisory Commission has reviewed the above-cited
request. The application, staff report and related materials are attached for your review.
Discussion
Staff Member Kyle Kritz reviewed the proposed text amendment, noting freestanding
solar arrays have been allowed in the Zoning regulations since 1985, and are regulated
as an accessory structure. Staff noted that accessory structures in residential districts
are allowed to be 1,000 square feet in area and 15 feet in height. Staff Member Kritz
reviewed four potential options for the Zoning Advisory Commission to consider:
1) Leave the Ordinance as is;
2) Require a conditional use permit for a freestanding solar array in residential
districts;
3) Create a threshold of 100 square feet and 10 feet in height for freestanding solar
arrays in residential districts that could be waived by the Zoning Board of
Adjustment through the Special Exception process; and
4) Prohibit freestanding solar arrays in residential districts altogether.
There were several public comments regarding the safety of solar arrays including
EMFs, children's safety and property values. Speakers also stated that solar arrays are
safe, meet all applicable electrical codes, and advance the City's sustainability goals.
One speaker pointed out the recommendation to limit arrays to 100 square feet is
unreasonable as it takes approximately 500 square feet to power a typical single-family
home. The speaker also suggested that the size of freestanding solar arrays should be
proportional to the size of the property.
Service People Integrity Responsibility Innovation Teamwork
The Honorable Mayor and City Council Members
Page 2
The Zoning Advisory Commission discussed the request, asking questions about the
safety of the wiring, the size of array necessary for a single-family home, the typical
height of a freestanding array, and reviewed the four options presented by Planning
staff.
Recommendation
By a vote of 7 to 0, the Zoning Advisory Commission recommends that the City Council
approve an amendment limiting freestanding solar arrays on residential property to 100
square feet in area and 10 feet in height, with the ability for a property owner wanting to
exceed the maximum standards to petition the Zoning Board of Adjustment for a Special
Exception.
A simple majority vote is needed for the City Council to approve the amendment as
recommended by the Zoning Advisory Commission.
Respectfully submitted,
Patrick Norton, Chairperson
Zoning Advisory Commission
cc: Rich Russell, Building Services Manager
Service People Integrity Responsibility Innovation Teamwork
rHa crrY os Dubuque City of Dubuque
Planning Services Department
Dubuque,IA 52001-4805
Masterpiece on the Mississippi Phone: 563-589-4210
P PP Fax: 563-589-4221
plannincj@cityofdubu ua e ora
PLANNING APPLICATION FORM
❑Variance ❑Preliminary Plat ❑Simple Subdivision ❑Certificate of Appropriateness
❑Conditional Use Permit ❑Major Final Plat ®Text Amendment ❑Advisory Design Review(Public Projects)
❑Appeal ❑Minor Final Plat ❑Temporary Use Permit ❑Certificate of Economic Non-Viability
❑Special Exception ❑Simple Site Plan ❑Annexation [--]Historic Designation
❑Limited Setback Waiver ❑Minor Site Plan ❑Historic Revolving Loan ❑Demolition
❑Rezoning/PUD/ID ❑Major Site Plan ❑Historic Housing Grant ❑Port of Dubuque Design Review
Please type or print legibly in in
Property owner(s): Phone:
Address: City: State: Zip:
Fax#: Cell #: E-mail:
Applicant/Agent: City of Dubuque Phone: 589-4210
Address: 50 W. 131h Street City: Dubuque State: IA Zip: 52001
Fax#: Cell #: E-mail: [)Ianning@citvtofdubuque.org
Site location/address: N/A Neighborhood Association: N/A
Existing zoning: N/A Proposed zoning: N/A District: N/A Landmark: ❑ Yes ❑ No
Legal Description(Sidwell parcel ID#or lot number/block number/subdivision): N/A
Total property(lot)area (square feet or acres): N/A
Describe proposal and reason necessary (attach a letter of explanation, if needed): Amend the Unified Development Code to
establish procedures for the review of new freestanding solar arrays in residential and office zoning districts
CERTIFICATION: I/we,the undersigned, do hereby certify/acknowledge that:
1. It is the property owner's responsibility to locate property lines and to review the abstract for easements and restrictive
covenants.
2. The information submitted herein is true and correct to the best of my/our knowledge and upon submittal becomes public
record;
3. Fees are not refundable and payment does not guarantee approval; and
4. All additional required written and graphic materials are attached.
Property Owner(s): Date:
Applicant/Agent: —_. Date:
FOR OFFICE USE ONLY—APPLICATION SUBMITTAL CHECKLIST
Fee: Received by: — Date: X477* Docket:
THE cbAd
irY or Dubuque
UB E
Masterpiece on the Mississippi
May 26, 2015
TO: Zoning Advisory Commission
FROM: Kyle L. Kritz, Associate Planner '• •
SUBJECT: Text Amendment for Residential Freestanding Solar Arrays
INTRODUCTION
The Zoning Board of Adjustment recently reviewed two special exception requests to
allow freestanding solar arrays to exceed either the accessory structure height limit or
accessory structure square footage in a single-family residential neighborhood. Most of
the adjacent property owners who spoke at those meetings were concerned with the
impact of a freestanding solar array on the use and enjoyment of their properties.
Planning staff is proposing a text amendment to the Unified Development Code to
establish height and size requirements for accessory freestanding solar arrays in
residential zoning districts.
BACKGROUND
Planning staff has put together a proposal for regulating freestanding solar arrays in
residential and office districts areas as an interim step in providing more comprehensive
requirements to facilitate the installation of both freestanding and building-mounted
solar arrays within the community.
As a backdrop to the recent requests before the Zoning Board of Adjustment, the City of
Dubuque is a pilot community for the Solar Ready Iowa Initiative. Being solar ready can
be defined as having a predictable, transparent process in place to receive the
necessary approvals to install solar installations.
Currently, the UDC allows freestanding solar arrays as an accessory structure in all
zoning districts. For residential districts, this would allow a freestanding solar array to
up to 1,000 square feet and 15 feet in height, the same as any other accessory
structure. These regulations have been in place since 1985. The two recent accessory
solar array installations reviewed by the Zoning Board of Adjustment are the first two
such requests since 1985.
Memo to Zoning Advisory Commission Page 2
Planning staff has done research on how other communities regulate freestanding solar
arrays, and they basically fall into three approaches:
I
The first approach is that a few communities, most notable being the City of Chicago, do
not allow freestanding solar arrays at all in residential areas.
A second approach, which is considered to be a 'Best Practice', is to establish a
threshold where below an established solar panel square footage and height, the solar
arrays are allowed by right. If either the height of the solar array or the panel size
exceeds the established limits, then a review and approval is required prior to
installation.
A third approach is to require that any freestanding solar array within a residential area
require review and approval prior to installation. Typically, this involves the review and
approval of a Conditional Use Permit.
A fourth approach is to not change the current regulations that allow freestanding solar
arrays as a permitted accessory structure in residential areas. Accessory structures are
limited to 15 feet in height and 1,000 square foot in area.
DISCUSSION
Planning staff is recommending that freestanding solar arrays be restricted to 100
square foot in area and 10 feet in height measured from the grade level to the highest
point of the structure. If either the square footage or height requirements are exceeded,
then a special exception will be necessary.
Planning staff is proposing to establish a threshold on square footage and height for two
principal reasons. One, by establishing the thresholds, it is viewed as a 'Best Practice"
in that a reasonably sized structure is allowed by right with no additional review other
than Building permits and is less costly. A Conditional Use Permit has a $333
application fee plus $2 per notice. A Special Exception fee is $133 and only the
adjacent neighboring property owners are notified.
Planning staff believes that a Conditional Use Permit for freestanding solar array would
be excessive, in that a solar array, while being physically quite different from a detached
garage, is still an accessory structure. Homeowners wishing to have an accessory
garage larger than what is allowed by Code, also only need apply for a Special
Exception and not a Conditional Use Permit. Planning staff also believes that the
notification of property owners within 200 feet is not necessary. Only the neighbors
directly adjacent to the property will typically have a view of the proposed installation.
Planning staff anticipates submitting a more comprehensive amendment to facilitate the
City becoming solar friendly. While establishing additional regulations does not at first
glance seem to promote the installation of solar arrays, appropriate regulations are
necessary to ensure that solar arrays are compatible with surrounding property. This
Memo to Zoning Advisory Commission Page 3
approach is similar to the regulations that exist for wind energy conversion systems and
communication towers and antennas.
RECOMMENDATION
Planning staff is recommending that residential and office districts in the Unified
Development Code be amended to continue to allow freestanding solar arrays, but limit
the area to 100 square foot and the height to 10 feet. Planning staff requests that the
Zoning Advisory Commission review the proposal and make a recommendation to City
Council on the proposed text amendment.
KLK/mkr
Attachments
rHa crrY os Dubuque City of Dubuque
Planning Services Department
Dubuque,IA 52001-4805
Masterpiece on the Mississippi Phone: 563-589-4210
P PP Fax: 563-589-4221
plannincj@cityofdubu ua e ora
PLANNING APPLICATION FORM
❑Variance ❑Preliminary Plat ❑Simple Subdivision ❑Certificate of Appropriateness
❑Conditional Use Permit ❑Major Final Plat ®Text Amendment ❑Advisory Design Review(Public Projects)
❑Appeal ❑Minor Final Plat ❑Temporary Use Permit ❑Certificate of Economic Non-Viability
❑Special Exception ❑Simple Site Plan ❑Annexation [--]Historic Designation
❑Limited Setback Waiver ❑Minor Site Plan ❑Historic Revolving Loan ❑Demolition
❑Rezoning/PUD/ID ❑Major Site Plan ❑Historic Housing Grant ❑Port of Dubuque Design Review
Please type or print legibly in in
Property owner(s): Phone:
Address: City: State: Zip:
Fax#: Cell #: E-mail:
Applicant/Agent: City of Dubuque Phone: 589-4210
Address: 50 W. 131h Street City: Dubuque State: IA Zip: 52001
Fax#: Cell #: E-mail: [)Ianning@citvtofdubuque.org
Site location/address: N/A Neighborhood Association: N/A
Existing zoning: N/A Proposed zoning: N/A District: N/A Landmark: ❑ Yes ❑ No
Legal Description(Sidwell parcel ID#or lot number/block number/subdivision): N/A
Total property(lot)area (square feet or acres): N/A
Describe proposal and reason necessary (attach a letter of explanation, if needed): Amend the Unified Development Code to
establish procedures for the review of new freestanding solar arrays in residential and office zoning districts
CERTIFICATION: I/we,the undersigned, do hereby certify/acknowledge that:
1. It is the property owner's responsibility to locate property lines and to review the abstract for easements and restrictive
covenants.
2. The information submitted herein is true and correct to the best of my/our knowledge and upon submittal becomes public
record;
3. Fees are not refundable and payment does not guarantee approval; and
4. All additional required written and graphic materials are attached.
Property Owner(s): Date:
Applicant/Agent: —_. Date:
FOR OFFICE USE ONLY—APPLICATION SUBMITTAL CHECKLIST
Fee: Received by: — Date: X477* Docket:
THE cbAd
irY or Dubuque
UB E
Masterpiece on the Mississippi
May 26, 2015
TO: Zoning Advisory Commission
FROM: Kyle L. Kritz, Associate Planner '• •
SUBJECT: Text Amendment for Residential Freestanding Solar Arrays
INTRODUCTION
The Zoning Board of Adjustment recently reviewed two special exception requests to
allow freestanding solar arrays to exceed either the accessory structure height limit or
accessory structure square footage in a single-family residential neighborhood. Most of
the adjacent property owners who spoke at those meetings were concerned with the
impact of a freestanding solar array on the use and enjoyment of their properties.
Planning staff is proposing a text amendment to the Unified Development Code to
establish height and size requirements for accessory freestanding solar arrays in
residential zoning districts.
BACKGROUND
Planning staff has put together a proposal for regulating freestanding solar arrays in
residential and office districts areas as an interim step in providing more comprehensive
requirements to facilitate the installation of both freestanding and building-mounted
solar arrays within the community.
As a backdrop to the recent requests before the Zoning Board of Adjustment, the City of
Dubuque is a pilot community for the Solar Ready Iowa Initiative. Being solar ready can
be defined as having a predictable, transparent process in place to receive the
necessary approvals to install solar installations.
Currently, the UDC allows freestanding solar arrays as an accessory structure in all
zoning districts. For residential districts, this would allow a freestanding solar array to
up to 1,000 square feet and 15 feet in height, the same as any other accessory
structure. These regulations have been in place since 1985. The two recent accessory
solar array installations reviewed by the Zoning Board of Adjustment are the first two
such requests since 1985.
Memo to Zoning Advisory Commission Page 2
Planning staff has done research on how other communities regulate freestanding solar
arrays, and they basically fall into three approaches:
I
The first approach is that a few communities, most notable being the City of Chicago, do
not allow freestanding solar arrays at all in residential areas.
A second approach, which is considered to be a 'Best Practice', is to establish a
threshold where below an established solar panel square footage and height, the solar
arrays are allowed by right. If either the height of the solar array or the panel size
exceeds the established limits, then a review and approval is required prior to
installation.
A third approach is to require that any freestanding solar array within a residential area
require review and approval prior to installation. Typically, this involves the review and
approval of a Conditional Use Permit.
A fourth approach is to not change the current regulations that allow freestanding solar
arrays as a permitted accessory structure in residential areas. Accessory structures are
limited to 15 feet in height and 1,000 square foot in area.
DISCUSSION
Planning staff is recommending that freestanding solar arrays be restricted to 100
square foot in area and 10 feet in height measured from the grade level to the highest
point of the structure. If either the square footage or height requirements are exceeded,
then a special exception will be necessary.
Planning staff is proposing to establish a threshold on square footage and height for two
principal reasons. One, by establishing the thresholds, it is viewed as a 'Best Practice"
in that a reasonably sized structure is allowed by right with no additional review other
than Building permits and is less costly. A Conditional Use Permit has a $333
application fee plus $2 per notice. A Special Exception fee is $133 and only the
adjacent neighboring property owners are notified.
Planning staff believes that a Conditional Use Permit for freestanding solar array would
be excessive, in that a solar array, while being physically quite different from a detached
garage, is still an accessory structure. Homeowners wishing to have an accessory
garage larger than what is allowed by Code, also only need apply for a Special
Exception and not a Conditional Use Permit. Planning staff also believes that the
notification of property owners within 200 feet is not necessary. Only the neighbors
directly adjacent to the property will typically have a view of the proposed installation.
Planning staff anticipates submitting a more comprehensive amendment to facilitate the
City becoming solar friendly. While establishing additional regulations does not at first
glance seem to promote the installation of solar arrays, appropriate regulations are
necessary to ensure that solar arrays are compatible with surrounding property. This
Memo to Zoning Advisory Commission Page 3
approach is similar to the regulations that exist for wind energy conversion systems and
communication towers and antennas.
RECOMMENDATION
Planning staff is recommending that residential and office districts in the Unified
Development Code be amended to continue to allow freestanding solar arrays, but limit
the area to 100 square foot and the height to 10 feet. Planning staff requests that the
Zoning Advisory Commission review the proposal and make a recommendation to City
Council on the proposed text amendment.
KLK/mkr
Attachments
Prepared by: Laura Carstens, City Planner Address: City Hall. 50 W. 13th St Telephone: 589-4210
Return to: Kevin Firnstahl, City Clerk Address: City Hall-50 W. 13 St Telephone: 589-4121
ORDINANCE NO. -15
AN ORDINANCE AMENDING TITLE 16 OF THE CITY OF DUBUQUE CODE OF
ORDINANCES, UNIFIED DEVELOPMENT CODE, BY AMENDING ARTICLES 16-5-2-2 (R-
1), 16-5-3-2 (R-2) 16-5-4.3(R-2A), 16-5-5.3(R-3) AND 16-5-6.3 (R-4), 16-5-7.3 (OR) AND
16-5-9.3(OC) TO ESTABLISH MAXIMUM AREA AND HEIGHT REQUIREMENTS FOR
RESIDENTIAL FREESTANDING SOLAR ARRAYS.
NOW, THEREFORE, BE IT ORDAINED BY THE CITY COUNCIL OF THE CITY OF
DUBUQUE, IOWA:
Section 1. That Title 16 of the City of Dubuque Code of Ordinances, Unified
Development Code Articles 16-5-2.3 (R-1), 16-5-3.3 (R-2), 16-5-4.3 (R-2A), 16-5-5.3 (R-3),
16-5-6.3 (R-4), 16-5-7.3 (OR) and 16-5-9.3 (OC) are hereby amended as follows:
5-2.3, 5-3.3, 5-4.3, 5-5.3, 5-6.3, 5-7.3, 5-9.3 Accessory Uses
Solar Collector (freestanding array[s] are limited to not more than 100 aggregate
square feet and 10 feet in height).
Section 2. The foregoing amendment has heretofore been reviewed by the
Zoning Advisory Commission of the City of Dubuque, Iowa.
Section 3. This ordinance shall take effect immediately upon publication, as
provided by law.
Passed, approved and adopted this day of 2015.
Roy D. Buol, Mayor
Attest:
Kevin S. Firnstahl, City Clerk
SOLARPLANETPOWERING FUTURE GENERATIONS
Date: 4/20/2015
To:City of Dubuque Zoning committee
From: Tim Mueller
Re:Proposed conditional use permit requirement for ground mounted solar installations
Mess: This proposed requirement adds another layer of complexity to the already burdensome process of
installing and commissioning solar PV systems.This whole idea not only delays construction deadlines but
it will add additional costs to the overall project.The entire solar industry has strived to get those costs as
low as possible to encourage multi-market growth.Adding additional costs and regulations will only
discourage growth and progress toward the City of Dubuque's effort to promote sustainability.
If a system meets all the criteria of the National Electric Code and passes all required inspections by both
the City of Dubuque and the local utility field engineers,it is thereby deemed safe to operate.If the PV
structure meets the local required setbacks and height requirements,it has met the criteria of any other
accessory use structure and should not be given additional scrutiny. The current building permit should be
sufficient regulation for these types of structures.The opinions of the neighbors should have no bearing on
whether or not you can build and operate a distributed generation PV system.
Here is some text from the DSIREUSA.org website:
Iowa's solar access easement provision allows for access to sunlight to operate a solar energy system. Those
who are unable to obtain a voluntary solar easement from a property owner may apply to the solar access'
regulatory board for an order granting a solar access easement if the relevant city council or county board
of supervisors has created such a board.In the absence of such a board,the matter is referred to the local
district court.Applications for an easement must contain specific information about the size,location,and
orientation of the solar energy system as well as a description of the actions that have been taken to
minimize the impact on neighboring estates.
Iowa code also grants municipalities the right to issue ordinances prohibiting subdivisions from including
restrictive covenants that limit the use of solar collectors.
I believe the rights of home owners who want to covert the sun's energy into electricity
should NOT be hindered from doing so, regardless of what a neighbor thinks about it.
Respectfully,
Tim Mueller D E E 0: d [E
President/Solar Planet Inc. D
MhY 2 0 '2015
CITY OF DUBUQUE
PLANNING SERVICES DEPARTMENT
5VLL _-&-6 6V -ne 8 96@tI
SOLAR RIGHTS
SARA C.BRONIN;
INTRODUCTION............................................................................................. 1218
I. WHY INDIVIDUAL SOLAR RIGHTS..................................................... 1222
IL EXPRESS AGREEMENTS..................................................................... 1225
A. Express Easements..........................................................:......... 1231
B. Covenants.................................................................................. 1236
C. Tenancy.....................................................................................
III. GOVERNMENTAL ALLOCATIONS....................................................... 1237
A. Permits....................................................................................... 1238
B. Zoning........................................................................................
IV. COURT ASSIGNMENTS OF RIGHTS..................................................... 12531
A. Nuisance....................................................................................
B. Prescriptive Easements............................................................. 1257
C. Implied Easements..................................................................... 1263
CONCLUSION................................................................................................. 1265
The rights to access and to harness the rays of the sun —solar rights —are
extremely valuable. These rights can detennine whether and how an
individual can take advantage of the sun's light, warmth, or energy, and they
can have significant economic consequences. Accordingly,for at least two
thousand years, people have attempted to assign solar rights in a fair and
efficient manner.
In the United States, attempts to assign solar rights have fallen short. A
quarter century ago, numerous American legal scholars debated this
deficiency. They agreed that this country lacked a coherent legal framework
for the treatment of solar rights, especially given the emergence of solar
collector technology that could transform solar energy into thermal, chemical,
or electrical energy. These scholars proposed several legal regimes that they
believed would clarify solar rights and facilitate increased solar collector use.
Very little has changed since this debate about solar rights began. Although
somejurisdictions have experimented with scholars'suggestions, reforms have
not been comprehensive, and solar rights are guaranteed in very few places.
At least in part because of the muddled legal regime, and despite numerous
Associate Professor of Law,University of Connecticut School of law. I would like to
thank Professors Jill Anderson, Eric Bluemel, Elizabeth Burleson, Peter Byrne, Nestor
Davidson,K.K. DuVivier, Alexandra Klass, Ruth Mason, Jim Salzman, Peter Siegelman,
and Kurt Strasser,and the faculties of Arizona State University,University of Connecticut,
and University of Denver for their help in shaping this piece.
1217
i
i
1218 BOSTON UNI VERSITY LA W RE HE W [Vol. 89:1217
technological advances that have reduced the cost of solar collectors, only one
percent ofou r nation's energy currently comes from the sun.
In this context, this Article aims to reinvigorate and refocus the scholarly
debate about solar rights. The Article first explains why solar rights are
valuable to both individuals and to the country as a whole. It then analyzes
three methods by which solar rights can be allocated- express agreements
behveen property owners, governmental permit systems or zoning ordinances,
and court assignments that result from litigation. Although this Article
analyzes the concerns of both solar rights seekers and possible burdened
parties with respect to current law, it does not fdly address the possible
solution to the problem oj'solar rights. Instead, this Article sets the stage for a
second piece, Modern Lights, simultaneously being published in the University
of Colorado Law Review.
INTRODUCTION
The rights to access and to harness the rays of the sun—solar rights—have
significant economic consequences. Solar rights dictate whether a property
owner can grow crops, illuminate her space without electricity, dry wet
clothes, reap the health benefits of natural light, and, perhaps most
significantly in our modern era, operate solar collectors — devices used to
transform solar energy into thermal,chemical,or electrical energy.'
For at least two thousand years,people have attempted to assign solar rights
in a fair and efficient manner.2 Ancient Romans protected the right to solar
heat and light through prescriptive easements, government allocations, and
court decrees? Ancient Greeks protected solar rights through rigid land
r See, e.g., NEB. REV. $'IAT. ANN. § 66-904 (West 2003) (defining a solar energy
collector to mean "a device, structure, or part of a device or structure which is used
primarily to transform solar energy into thermal, chemical, or electrical energy"); John
Lungren, Solar Entitlement. A Proposed Legislative Model,4 J.ENERGY L. &POL'Y 171,
186 (1983) (proposing a model statute and defining a "solar energy collector" to be "a
structure or portion of a structure which is used to convert solar energy into thermal,
chemical, or electrical energy, including any space or structural components specifically
designed to retain heat derived from solar energy and any mechanism specifically
maintained to produce photosynthetic products"). The term includes such devices as hot
water heaters, photovoltaic panels, devices for heating and cooling, domestic hot water
systems, pumps, and devices for supplying energy for commercial, industrial, and
agriculture processes. -
3 See Melvin M.Eisenstadt,Access to Solar Energy:The Problem and Its Current Status,
22 NAT.RESOURCES J. 21, 21 (1982) ("For at least the past 2,000 years, man has heated
buildings with solar energy and designed such buildings with access to the needed
sunshine.").
3 GAIL BUYER HAYES,SOLAR ACCESS LAN:PROTECTING ACCESS TO SUNLIGHT FOR SOLAR
ENERGY SYSTEMS 14(1979)(describing an inscription on the Temple of Apollo at Pompeii,
which states that the local government had to compensate property owners because a temple
blocked their sunlight);Borimir Jordan&John Perlin,Solar Energi, Use and Litigation in
2009] SOLAR RIGHTS 1219
planning schemes that oriented streets and buildings to take advantage of light
and passive solar heat More recent rules — such as the so-called "ancient
lights" rule established in medieval England or the permit system currently
used by Japan — have continued to refine the concept of solar rights.5 Each
regime has recognized that sunlight, in reaching any one parcel, may travel
across multiple parcels, and its route may vary throughout the day and from
day to day. By necessity,then,the creation of solar rights implicates the rights
of neighbors,both immediate and further afield.
In the United States,solar rights have fallen short,either because they do not
exist or because,where they do exist,they provide inadequate protection to the
holders of the rights. In the late 1970s and early 1980s, numerous American
legal scholars debated these deficiencies. These commentators agreed that the
absence of a coherent legal framework for the treatment of solar rights had
negative consequences, chief among which was the dampening effect on the
use of solar collectors. In their view, solar collector's produced an
environmentally-friendly,inexhaustible,and economically secure alternative to
carbon-based fuels.b The law,they argued, should encourage the proliferation
of clean energy by providing rights to solar collector owners. These scholars
advanced several proposals to change the law to meet this goal. Their
Ancient Times, 1 SOLAR L.REL,.583,592-93(1979)(observing that`Roman sun rooms were
common enough to provoke disputes over solar rights and judicial decrees to settle them");
Stephen Christopher Unger, Ancient Lights in fElgleyville: An Argument for Bre
Unobstructed View of a National Pastime,38 IND.L.Rev. 533,548(2005)(observing that
"Roman law enforced solar rights as an important source of light and heat").
4 Jordan & Perlin,srpra note 3, at 585-86 (asserting that Greek planning considered
solar energy as early as the fifth century B.C.E. and describing a Greek city whose houses
were laid out in a north-south orientation designed to take advantage of passive solar
heating). Greeks did not limit their expertise in solar design to buildings;Archimedes used
a solar concentrator to bum enemy ships. Donald N. Zillman &Raymond Deeny, Legal
Aspects of Solar Energy Development, 1976 ARIZ.ST.L.J.25,26.
s See PATRICK J.DALTON,LAND LAW 189(1972)(describing how English courts applied
the"ancient lights"concept of negative easements to light and air rights by the seventeenth
century);Gail Feingold Takagi,Designs on Sunshine:Solar Access in fire United States and
Japan, 10 CONN.L.Rev. 123, 146(1977)(describing Japan's motivation for defining solar
rights to be"securing sunlight for health,with energy conservation of marginal relevance").
I W. Wade Berryhill&William H. Parcell III, Guaranteeing Solar Access in Virginia,
13 U. turn. L. REV. 423, 425 (1979); David L. Bersohn, Securing Solar Energy Rights:
Easements,Nuisance, or Zoning?,3 COLUM.J.ENVTL.L. 112, 112(1976-1977)(observing
that solar energy,unlike traditional forms of energy,"does not cause land surface spoliation,
black lung and the smog-related respiratory and cardiovascular diseases, oily seas, or
thermal or radiological pollution"); see also Ziliman & Deeny, supra note 4, at 25
(describing the effects of the 1973 oil embargo,such as long lines at the filling stations,as
well as fears about nuclear power). Bersohn also recognizes some of the drawbacks of solar
energy:"Central solar power generation involves extensive land use preemption,and might
cause local aquatic thermal pollution and disrupt atmospheric circulation patterns."
Bersolm,supra,at 113.
1220 BOSTON UNIVERSITYLAWREVIEW [Vol. 89:1217
proposals ranged from revisions to existing statutes,to the rise of nuisance suits
to bar neighbors from blocking one another's light, to the creation of permit
systems or zoning ordinances which administratively allocate solar rights.
By the mid-1980s, one commentator observed that "[a]Ithough these
alternatives have been the subject of arguments for years,a clear policy has not
yet emerged."t To date, despite scholars' efforts, progress with respect to the
clarification and efficient allocation of solar rights has been slow. A few
jurisdictions have experimented with their suggestions, but reforms have not
been comprehensive, and solar rights are guaranteed in very few jurisdictions.
At least in part because of the muddled legal regime, and despite numerous
technological advances that have reduced the cost of solar collectors, only one
percent of our nation's energy currently cones from the sun.$ Many
cormnunities, reeling from record-high oil prices in 2008, have expressed an
interest in prioritizing solar energy, but the tension between the legal system
and solar collector usage has not been resolved.
In the context of an increasingly urgent debate over global warning and the
need to reduce America's dependence on carbon-based fuels,this Article ahris
to reinvigorate the scholarly debate about solar rights,with a focus on the solar
collector as one important use. Part I explains why we should reinvigorate the
debate: solar access is valuable not just to individuals, but also to the country
as a whole. Part I also argues that we need individual, as opposed to
communal,solar rights. The Article goes on to present three primary methods
by which solar rights are currently allocated to and among individuals: express
agreements between property owners, governmental allocations, and court
assignments. In analyzing each method, this Article focuses on two concepts:
first, efficiency, defined as the extent to which the rights are in the end
allocated to those who value them most and that proper compensation is paid
to those who are hurt by such allocation; second, transaction costs, which are
the administrative, monitoring, and/or information costs incurred during an
exchange of a right, beyond the cost of the right itself. Although these two
I Lungren,supra note 1,at 172("Solar access is not a new legal issue, Minimal access
protection has been sought through application of land use controls,nuisance doctrine,prior
appropriation,easements,and restrictive covenants."),
a Yuliya Chernova, Shedding Light on Solav, WALL ST. J., June 30, 2008, at R6
("[D]espite subsidies that have helped push up demand, solar power still accounts for less
than 1%of power generation in the U.S. That's because even with subsidies, solar power
remains expensive compared with energy based on traditional fuels like coal and natural
gas.").
9 See, e.g., SCOTT ANDERS, KEVIN GRIGSBY S' CAROLYN ADI KUDUK, UNTV. OF SAN
DIEGO SCI. OF LAW, CALIFORNIA'S SOLAR SHADE CONTROL ACT: A REVIEW OF THE
STATUTES Arm RELEVANT CASES 1 (2007) (documenting the goal of the California Solar
Initiative to multiply the photovoltaic megawatt production by nearly seventeen times and
asserting that"[s]uch a drastic increase in the number of operating photovoltaic systems in
addition to the anticipated increase in solar water heaters could multiply solar access
questions arising from these installations").
2009] SOLAR RIGHTS 1221
concepts clarify the shortcomings of existing solar rights,increasing efficiency
and reducing transaction costs may not be the only goals for an ideal future
solar rights regime, a topic that is considered in a companion piece to this
Article. Attention is also paid to which patty — the benefited party or the
burdened party — has the initial entitlement under each regime, as the
assignment of the initial entitlement can influence both efficiency and
transaction costs.10
Express agreements, such as express easements, covenants, and tenancy
arrangements, are discussed in Pail It. Through an express agreement, two or
more property owners can agree to a method of allocating solar rights,
provided that the government does not prohibit such methods, or, even better,
expressly allows them. The initial entitlement in these cases is, by default, in
the hands of the burdened party or, when a solar collector is involved, in the
hands of the potential obstructer. From an efficiency standpoint, these
arrangements are perhaps the most effective means of allocation. In the ideal
case,they involve parties with some knowledge about the rights they have(and
choose to relinquish)or receive(and choose to pay for). These parties bargain
based on the values they respectively place on the receipt or relinquishment of
that right. Unfortunately, express agreements involve very high transaction
costs. Individuals may be required to pay for attorneys, conduct title searches,
and spend valuable time drafting express agreements. Moreover,the exchange
of a solar right using an express agreement may involve multiple parties who
take too long to(or never)agree on the appropriate allocation.
Part III of this Article describes how the government can allocate solar
rights —an arrangement that may in some ways be more efficient with respect
to transaction costs than the express agreements described in Part II.
Governmental allocations may occur through the award of solar permits or
through zoning decisions. Typically, these rights are awarded through
standard procedures that usually include petitioning a public decision-making
body. Depending on the regime,the initial entitlement may be in the hands of
either the benefited or burdened party: a zoning ordinance, for example,might
establish solar rights for all owners of solar collectors within its jurisdiction,
whereas a permit system might exist where the default rule is the absence of
solar rights for anyone. In one sense,transaction costs may be low because the
process is well defined: it public body must typically make a decision in
accordance with established rules and schedules. hi other respects, however,
government awards may be quite costly: the individualized allocation process
can be tedious,and may still require that rights seeker's hire attorneys and other
professionals. More significantly, government allocations are far from
predictable or uniform, and do not necessarily result in awards that are truly
justified on efficiency grounds.
10 See Sara C. Broom, Modern Lights, 80 U. Core.L. REv. (forthcoming Nov. 2009)
(describing in Part 11 the consequences of the assignment of the initial entitlement).
1222 BOSTON UNIVERSITYLAWREVIEW [Vol. 89:1217
Finally,Part IV deals with court-assigned rights—perhaps the least efficient
and most costly method of obtaining a solar right. In the rare instance in which
a court has considered solar rights —using nuisance,prescriptive easement, or
implied easement principles—it usually has failed to award solar rights to the
party who could maximize their use. As one cormmentator observed, "The
courts are a weak ally to the contemporary solar energy user."11 Transaction
costs are highest (when compared with the other two methods considered by
this Article) for court-assigned rights. Each case may be very complicated,
and litigation is expensive relative to the value of the right.
The three current methods of allocating solar rights vary greatly, and
although each attempts to balance competing interests, each falls short in
certain respects. Throughout Parts 1I through IV, this Article dissects the
inability of the current legal regime to respond to the pressing problem of solar
rights. The criticisms contained here are not meant to imply that the current
regimes are unsalvageable. Rather, they underscore the need for a new
approach to solar tights. A companion piece to this Article will flesh out some
elements of the new approach.1z
I. WHY INDIVIDUAL SOLAR RIGHTS
Except in a few limited circumstances, the American legal system has not
recognized the solar right—the ability of a property owner to enjoy or utilize a
defined amount of sunlight on her parcel and to defend this right as against
other property owners. Yet there are at least two strong reasons for this _
country to do so,especially as such rights might apply to solar collectors.
First,solar access is extremely valuable to the individuals who have it. The
quality and amount of sunlight which reaches a structure's interior, for
example, affects three economic measures: the resale price of the structure, as
buyers will pay premiums for naturally lit space; the productivity of the
structure's occupants, who work better with sunlight than artificial light; and
the operating costs of heating, cooling, and lighting systems.13 Similarly, the
use of sunlight in outdoor areas can have financial consequences: a property
owner can grow garden vegetables, produce commercial crops for resale, or
use sunlight instead of electricity to dry laundry—all of which save or generate
income. Perhaps most importantly, solar collectors, for which sunlight is the
primary and essential ingredient, almost always save owners more in energy
costs than the purchase price, and rapid technological developments have
U Kenneth James Potis,Solar Access Rights in Florida: Is There a Right to Sunlight in
the Sunshine State?,10 NovA L.J. 125,145(1985).
12 Bronin,Modern Lights,supra note 10.
13 GREGORY H. KATS, THE COSTS AND FINANCIAL BENEFITS Or GREEN BUILDINGS: A
REPORT TO CALIFORNIA'S SUSTAINABLE BUILDING TASK FORCE 65(2003)(summarizing the
results of eight studies which indicated that natural light helped to increase worker
productivity by a mean of 7.1"/o); Franklin Gewrtz, Obstruction of Sunlight as a Private
Nuisance,65 CAL.L.REV.94, 106(1977).
20091 SOLAR RIGHTS 1223
rendered them increasingly more valuable and will continue to do so in years
to come.14 The recognition that solar access has value to individuals must
serve as the basis for any solar rights regime.
Second, a solar rights regime also has value to the county as a whole.
There is increasing awareness of the dangers of overdependence on fossil
fuels, both from an environmental and geopolitical standpoint. However, our
failure to consider solar rights appropriately has dampened investment in
domestic solar collectors — efficient producers of clean energy—because it is
difficult to justify substantial up-front investments in solar collectors without a
guarantee of solar access. The reluctance to invest in solar collectors has
affirmed our dependence on foreign fossil fuels. The energy conservation and
energy security rationales for solar rights go hand in hand and have been
discussed for decades.IS A chorus of commentators writing thirty years ago
praised solar energy and solar collectors and called our failure to recognize
solar rights "an impediment to widespread conversion to solar energy,"16 "the
single most important legal issue concerning solar energy,"° and "the major
legal issue associated with solar energy."18 Although the need for guaranteed
property rights in solar access has grown more acute,we have failed to modify
the law to provide thein.
In light of these two important reasons for a solar rights regime, it is worth
emphasizing why this regime must be tailored to provide rights to individual
property owners. Some might question the need for complex legal systems
that support small-scale individual, as opposed to large-scale communal, solar
installations. They might point to the fact that investors have purchased large
14 See, e.g., U.S. ENVTL. PROTEC'T'ION AGENCY, IMPROVE ENERGY EFFICIENCY WITH
SOLAR WATER IIEATING (2001), available at http:/hvww.energystar.gov/ia/new_homes/
features/BSSolarWaterHeating.pdf(observing that fifteen to twenty-five percent of energy
use in residential buildings is devoted to heating hot water, and a solar water heater can
reduce annual operating costs by up to eighty percent); SANDY F.KRAEMER,SOLAR LAw:
PRESENT AND FUTURE,w1TH PRorosrD Foams 7 (1978)(observing that"[iln buildings,the
overwhelming bulk of the average building's energy requirement,70%or more,is for low-
grade heat which can be provided by solar systems").
" See, e.g., Sophia Douglass Pfeiffer, Ancient Lights: Legal Protection of Access to
Solar Eneig➢,68 A.B.A.J.288,291 (1982)(asserting that"[]t would indeed be regrettable
if the demonstrated need For utilization of solar energy— a technological reality today—
were to be left unmet because of the modern legal system's inability to devise adequate
measures to protect solar access"); cf. Takagi, supra note 5, at 146 (describing Japan's
rationale for solar access as being "based upon securing sunlight for health, with energy
conservation of marginal relevance").
16 Dale D.Goble,Solar Rights:Guaranteeing a Place in the San,57 OR.L.REV.94,134
(1977). Goble also called the access issue"the fundamental legal impediment"to the rise of
solar collectors. Id.at 97-98.
Berryhill&Parcell,supra note 6,at 426.
Is Adrian J.Bradbrook,Future Directions in Solar Access Protection, 19 ENVTL.L. 167,
168(1988).
1224 BOSTON UNIVERSITYLAWREVIEW [Vol.89:1217
tracts of rural land across the country to collect and distribute solar power to
multiple end users.19 Large solar installations on vast rural parcels with few
neighbors may not require a full solar rights regime. If this country could
depend on large installations, it might be argued, no individual solar rights
regime is necessary.
Yet we cannot depend on large installations to satisfy all solar power
demand. They do not, and could not, produce enough energy to meet ever-
rising demands for green power. The end users of large installations include
only those people who live within the area that can be reached by transmission
lines. Many large installations are concentrated in the South and the West,and
do not serve individuals in other parts of the country. Even those who do
receive solar power from large plants might receive less than they should, as
capacity is lost during transmission through notoriously inefficient electric
lines. Finally, large solar installations have been criticized (and sometimes
stalled) by environmental advocates who believe that they disrupt delicately
balanced ecological systems 20
While the growing number of large installations may signal that the market
has begun to embrace the economies of scale, the need for small installations
remains. Individual solar collectors can serve the many end users that are not
reachable by large solar installations. In addition, individual solar collectors
allow individuals to benefit directly from their investment; solar power offered
by the owners of large installations is not generally sold to end users at cost,
but instead at prices which approach conventional power prices. When it
comes to the environment, individual solar collectors have a smaller negative
impact than do large installations. And finally, individual solar collectors are
more efficient than large installations because they are installed near the end
user,meaning that little is lost during transmission.
In theory, there is a middle ground between the individual solar collector
and the large solar installation: a mid-sized facility,which might, for example,
serve a small urban neighborhood with costs divided equally among neighbors
within a few blocks. This Article does not consider the legal complexities that
relate to such shared generation because each state's rules differ significantly.
Mid-sized facilities generating power to multiple end users might,for example,
have to incorporate as an electric utility, file paperwork with the public utility
control commission, submit to the governance of an electric cooperative, or
19 See, e.g.,Todd Woody, The Southwest Desert's Real Estate Room,CNNMoNEY.coM,
July 11, 2008, hop://money.cnn.con/2008/07/07/technologyhvoody_solacfortune/
index.htm(focusing on land banking in the Mojave Desert for solar uses).
20 Id;see also Bersohn,supra note 6 at 113 ("Central solar power generation involves
extensive land use preemption,and might cause local aquatic thermal pollution and disrupt
atmospheric circulation patterns").
20091 SOLAR RIGHTS 1225
obey other rules. Most states' rales are so onerous that mid-sized solar
facilities are rare 21
Yet it is worth noting that some issues faced by individual landowners with
respect to solar rights would also be faced by those who collectively form a
mid-sized solar facility, especially in urban areas. The mid-sized facility, like
the individual solar collector owner, would somehow have to obtain rights
across other parcels to ensure solar access. Similarly, although large-scale
rural installations might not seem to require solar rights initially, the need for
solar rights may arise if development patterns around the installation site
change. Even though this Article focuses on individual solar rights, any
advance in solar rights would also benefit operators of mid-sized and urban
solar facilities,or even large-scale or rural installations. This Article will now
examine some of the methods for allocating solar rights, whatever the size of
the need.
11. EXPRESS AGREEMENTS
The first and perhaps most straightforward method of assigning solar rights
is by express agreements between private parties,where these agreements have
been implicitly or explicitly authorized by law. Express agreements are the
most efficient means of allocating solar rights to the respective parties: each
party understands her rights and has received compensation in some form or
amount to which she has consented. Usually, the compensated parties are
those who would have had the initial entitlement under the law—the burdened
parties, and not the solar rights seekers. Used as devices to reassign these
initial entitlements, express agreements come with significant transaction
costs: bargaining is time-consuming and expensive, especially when attorneys
must be hired and formalities must be followed.22 Transaction costs may be
particularly high in bilateral monopoly situations,where the possible parties to
an express agreement are limited to a small number of individuals.23 These
costs hinder the creation of express solar agreements"
Despite the costs, the law has allowed at least three types of express
agreements to serve as the basis for a solar right. The first type, express
easements, typically involves neighbors in established areas and requires
individualized negotiation. The second, covenants, which bind current and
subsequent owners, function best in new residential subdivisions but are
21 In a search,the author could not find any examples of shared solar cooperatives of this
nature.
22 Any time bargaining is required, as it is in the case of express agreements, high
transaction costs are likely. See Robert Cooter, The Cost of Corse, I I J.LEG.STUD. 1,23
(1982).
21 See,e.g.,ROBEKr COOTER Q'.THOMAS ULEN,LAW AND ECONOMICS(2007).
24 Admittedly,data on this point is limited,and determining the number of express solar
agreements in the country is,practically speaking,impossible;however,the infrequency of
their appearance in courts and in legal literature reveals that these barriers are significant.
1226 BOSTON UNIVERSITYLAWREVIEW [Vol. 89:1217
difficult to enact in established or nonresidential areas. Third, and least-used,
lessor-lessee arrangements tie the solar right to the term of tenancy — a
limitation that hinders up-front investment in solar collectors. Although each
of these agreements has a slightly different nature,each might be instructive in
considering a better solar rights regime.
A. Express Easements
The creation of an easement requires rigorous bargaining by multiple
parties,and the resulting high transaction costs prevent large-scale adoption of
easements that guarantee solar rights. Easements allow one landowner (the
dominant owner) to have certain rights over the real property of another
landowner (the servient owner)25 These rights take one of two forms:
affirmative rights that entitle the dominant owner to physical access of the
servient parcel; and negative rights that encumber the servient owner's use of
her property,usually preventing the servient owner from undertaking particular
activities. An easement does not grant the dominant owner ownership rights,
but rather allows the dominant owner to enforce the rights contained in the
easement. These enforcement powers endure, and remain with the land for
subsequent purchasers, until and unless some event or condition renders them
unenforceable.
Solar easements, a kind of negative easement, can create solar rights
between dominant and servient owners by burdening the servient owner's use
of her property.26 More specifically, a solar easement can prevent a servient
owner from improving her property in a way that blocks sunlight from falling
on all or part of the dominant estate (in effect, defining a solar skyspace).
Although it is possible to argue that the common law contemplates solar
easements, legislation allowing landowners to create express solar easements
avoids ambiguity and has become popular.27 At least twenty-eight state
statutes allow the creation and recording of express easements for solar access
by private landowners 28 Solar easement statutes do not themselves create
25 BLACK'S LAN DICTIONARY 585-86(9th ed.2009).
261d. at 587 (defining a "negative easement" as "[a]n easement that prohibits the
servient-estate owner from doing something,such as building an obstruction").
27 See Adrian J.Bradbrook,Australian and American Perspectives on the Protection of
Solar and Wind Access, 28 NAT. RESOURCES J. 229, 238 (1988) (explaining that "[w]ith
respect to solar access,the most widespread form of legislation adopted in the United States
is legislation recognizing the validity of an easement for solar access").
28 ALASKA STAT. § 34.15.145 (2008) (requiring writing and recording of the size of the
easement,any terms and conditions,and compensation for"[a]n easement obtained for the
purpose of protecting the exposure of property to the direct rays of the sun"); CAL. CIV.
CODE § 801.5 (West 2007); COLD.Rim. STAT. §§ 38-32.5-100.3 to-103 (2008) (allowing
injunctive relief"[i]n addition to other legal remedies"); FLA.STAT.ANN. § 704.07 (West
2000) (requiring six elements in written and recorded easements and protecting solar
easements from extinguishment by allowing a solar collector owner to file a notice); GA.
CODE ANN. §§ 44-9-20 to -23 (2002) (requiring that solar easements be in writing and
20091 SOLAR RIGHTS 1227
include a description of airspace and any terms and conditions of the granting or
termination);IDAHO CODE ANN.§55-615(2007)(requiring writing and recording of the size
of the easement,any terms and conditions,and compensation for an casement`obtained for
the purpose of exposure of a solar energy device to sunlight"); 30 ILT.Come. STAT.ANN.
725/1.2 (West 2001 & Supp. 2008) (allowing solar skyspace easements for structures,
vegetation,or other activity as long as the easement is described in three-dimensional terms
and includes "performance criteria for adequate collection of solar energy"); IOWA Cone
ANN.§564A.7(West 1992)(requiring that solar access easements be in writing and include
a"legal description of the dominant and servient estates"and of the space through which the
casement extends, in addition to optional provisions such as compensating the burdened
owner);KAN,SEAT.ANN. §§ 58-3801 to-3802 (2005);Ky.REV.SzA'r.ANN.§ 381.200(2)
(LexisNexis 2002)("A solar easement may be obtained for the purpose of ensuring access
to direct sunlight"); ME. Rev. STAT. ANN. tit. 335 § 1401 (1999) (providing that such
easements run with the land and are subject to court-decreed abandonment and other
limitations); MD. CODE ANN., REAL PROP. § 2-118 (LexisNexis 2003) (establishing an
"incorporeal property interest . . . enforceable in both law and equity" for casements,
conditions, or restrictions which relate to the "[p]reservation of exposure of solar energy
devices"); MINN. STAT. ANN. § 500.30 (West 2002 & Supp. 2009) (analogizing solar
easements to any other conveyance and providing enforcement for solar easements by
injunction or other proceedings in equity);MO.ANN.Scree. §442.012(West 2000)(calling
solar energy a"property right,"not subject to eminent domain,for which easements must be
expressly negotiated);MONT.CODE ANN. §§ 70-17-301 to-302(2007)(requiring that size,
terms and conditions,and termination provisions of an casement be in writing);NEB.REV.
STAT. §§ 66-909 to -911 (2003) (defining a "solar skyspace casement" and requiring a
description of the vertical and horizontal angles of the easement); NEV. Rev. STAT. §§
111.370-.380 (2007) (providing detailed definitions of the easement, its vesting, and three
methods of termination); N.H. Rev. STAT. ANN. §§ 447:49-:50 (2001) (defining a "solar
skyspace easement"to include the casement form and requiring certain information to be
provided therein); N.S. STAT. ANN. §§ 46:3-24 to -26 (West 2003) (requiring writing and
recording of the size of the easement,any terms and conditions,and compensation);N.D.
CENT. CODE §§ 47-05-01.1 to .2 (1999); OHIO REV. CODE ANN. § 5301.63 (LexisNexis
2004) (describing five necessary elements for solar access casements and allowing for
owners of benefited land to access any equitable remedy and damages for obstruction);OR.
REV.STAT.ANN. §§ 105.890,.895(West 2003 &Sapp.2008);R.I.GEN.LAWS§§ 34-40-1
to -2 (1995) (defining "solar easement" to include restrictions, easements, covenants, or
conditions to a deed "for the purpose of ensuring adequate exposure of a solar energy
system");TENN.CODE ANN. §§66-9-204 to-206(2004)(providing the statutory assumption
that such easement mus with the land);UTAH CODE ANN.§§57-13-1 to-2(2000)(defining
solar easements,setting out writing requirements and allowing enforcement by injunction);
VA.CODE ANN.§§55-352 to-354(2007)(requiring writing and recording of the size of the
easement, any terms and conditions, and compensation for solar easements); WASH.REV.
CODE ANN.§§64.04.140-.170(West 2005)(including the requirement for a"description of
the extent of the solar easement which is sufficiently certain to allow the owner of the real
property subject to the easement to ascertain the extent of the easement," and providing
remedies such as actual damages, reasonable attorney's fees, and injunctions); WIS. STAT.
ANN. § 700.35 (West 2001) (defining `renewable energy resource casement" as "an
easement which limits the height or location, or both, of permissible development on the
i
i
1228 BOSTON UNIVERSITYLA W REVIEW [Vol. 89:1217
easements, but allow private entities and political subdivisions to create
thern.29 The majority of states require such easements to be in writing and
contain detailed information about the size of the affected space,the manner of
termination,and compensatiou.30 In most jurisdictions,the easement must also
be recorded on the land records, to provide notice to individuals researching
the dominant or servient estates.
Express solar easements have several benefits. Most obviously, each party
to an easement has voluntarily bargained to a mutually agreeable result: the
dominant owner receives a solar corridor, while the servient owner receives
compensation to offset her burden 31 Another key advantage for dominant
owners is the receipt of a property right that is usually permanent and
irrevocable.32 Finally, private parties make and enforce solar easements,
therefore obviating the need for unnecessary governmental bureaucracy.33 As
burdened land in terms of a structure or vegetation, or both, for the purpose of providing
access for the benefited land to wind or sunlight passing over the burdened land").
29 See Lungren,supra note 1, at 180. Bu!see O'Neill v. Brown,609 N.E.2d 835, 840
(111. App. Ct. 1993) (finding that the Illinois Comprehensive Solar Energy Act, 30 ILL.
Comm.STAT.72511.2(f)(1)(2008),defined a solar skyspace easement but did not allow such
easements to be created).
30 See John William Gergacz,Legal Aspects of Solar EnergF:Statutory Approaches for
Access to Sunlight, 10 B.C. ENVTL. AFF. L. REv. 1, 11-12 (1982); Dennis L. Phelps &
Richard R. Yoxall, Solar Energy:An Analysis of the Implementation of Solar Zoning, 17
WAsHJmRN L.J. 146,150-51 (1977-1978);Erik J.A.Swensen et al.,State and Local Policies
Affecting the Advancement of Renewable Energy Sources, ABA ENERGY COn\4S.
NEWSLETTER, Jan. 2007, at 10, available at http:/hvww.abanct.org/environicommittees/
energy/newsletter/j an07/cnergyOI07.pdf.
31 See,e.g.,Eisenstadt,supra note 2,at 25;Shawn M.Lyden,An Integraled Approach to
Solar Access, 34 CASE W.Rrs.L.Rev.367,395 (1983-1984);Stephen F. Williams,Solar
Access and Property Rights: A Maverick Analysis, 11 CONN. L. REv. 430, 437 (1979)
("Setting aside occasional lunacies, no one will sell solar rights to a neighbor unless the
consideration is at least equal to the value of what he foregoes,in terms of opportunities to
enlarge his house,grow trees,or whatever. And since no one will pay more for solar rights
than what they are worth to him,all transfers that occur will be beneficial ones."). Bal see
Dale D. Goble, Solar Access and Property Rights: Reply to a "Maverick" Analysis, 12
CONN.L. Rev. 270, 283-84 (1979) (criticizing Williams's assumption that efficiency can
determine entitlements,arguing instead that entitlements determine efficiency).
32 See, e.g., LIoward R. Osofsky, Salar Building Envelopes: A Zoning Approach far
Protecting Residential Solar Access, 15 URB.LAW.637,639-40(1983);Donald N.Zillman,
Common-Law Doch•ines and.Solar Enelgt; in LEGAL ASPECTS OF SOLAR ENERGY 25, 31
(John H.Minian&William H.Lawrence eds., 1981)("The easement is a satisfactory legal
device for the solar user. Ile has no particular desire to own the neighbor's property. He
only needs to keep adequate direct sunlight streaming across the neighbor's land to his
collectors or passive construction. This limited use can allow the neighbor to retain a wide
variety of uses on his property,including the installation of solar equipment of his own.").
33 Osofsky, supra note 32, at 641 ("Solar easements require minimum government
involvement and are not affected by zoning changes on adjacent property.'). But see infra a
2009] SOLAR RIGHTS 1229
a result of these benefits, as one scholar put it, solar easement statutes have
become a popular and"inexpensive form of legislative cheerleading."34
This form of"legislative cheerleading"has not,however, home much fruit:
a search of federal and state cases revealed not it single case dealing with
express solar easements.35 An optimist might suggest that the lack of cases
reveals that express easements function well. More likely, it reflects the fact
that such easements are rare. Indeed,the primary benefit of the solar easement
— its voluntary nature — may also prevent its widespread adoption. Potential
obstracters might disagree on the terms of an easement or refuse to negotiate
altogether.36 Even when all patties agree to negotiate, solar easements take
time to formulate.37 Moreover, negotiations cost money — not just for
attorneys' fees, recording fees, and other administrative costs, but for the
easement itself, as a servient owner will more likely sell a solar casement than
donate it.38 Servient owners may overcharge for easements, either because
they overvalue their interests39 or because their relationships with the dominant
owners function as a bilateral monopoly, each side being the only possible
party to a transaction.40 These costs may increase the already-high cost of
text accompanying notes 45-52 (describing Iowa's approach in which state government
plays a role in the creation of solar easements).
J4 Zillman,supra note 32,at 32.
35 The author conducted several such searches and found no such cases.
36 Osofsky,supra note 32,at 641. The lone exception to this grant of initial entitlements
occurs in Iowa. See infra text accompanying notes 45-52.
31 See Goble, supra note 31, at 287 (asserting that unequal bargaining positions, the
possibility of multiple parties, novelty, inertia, and drafting complexities increase
transaction costs);Williams,sopa note 31,at 437-40(reasoning that transaction costs may
be higher in developed areas than in areas which are not yet developed).
38 Tamara C. Sampson &R. Alta Charo,Access to Sunlight:Resolving Legal Issues to
Encourage the Use of Solar Energy, Il Cot.um.J.ENVTL.L.417,424(1986)("The costs of
the easement include both substantive costs for the restrictions on property use, and
transaction costs,such as drafting agreements.").
39 See Williams,supra note 31, at 443 (identifying landowners' competing claims: for
the solar collector, lower energy costs; for the neighbor, the desire to perhaps enjoy full-
grown trees, whose shade could lower the neighbor's energy costs); Felicity Barringer,
Trees Block Solar Panels, and a Feud Ends in Court, N.Y. TIMES, Apr. 7, 2008, at A14
(describing two California neighbors'competing interests in redwood trees and solar access
for photovoltaic panels).
40 Cf. Lydon, sapra note 31, at 395 (stating that "even a cooperative landowner may
charge the solar user an exhorbitant[sic] price for the casement"and"easements are only
capable of protecting access for sited solar systems"); Carol Polis,Note,Obtaining Access
to Solar Energy:Nuisance, Water Rights, and Zoning Administration,45 BROOK.L.REV.
357, 364 (1978-1979) (stating that such agreements "possibly curtail[] the use of this
alternative energy source because the owner of the airspace could demand an exorbitant
price").
1230 BOSTON UNIVERSITYLAWREVIEW [Vol. 89:1217
solar energy systems and make them less attractive than cheaper forms of
energy.41
At least some of these costs stem from the assignment of initial entitlements:
in the vast majority of jurisdictions, the initial entitlement rests with the
potential obstructer,or the potential servient owner.42 The potential obstructer
may never agree to an casement; even if she does, she has the power to set a
high price on the easement.43 Because express easements often involve
bilateral monopolies, an individual party can hold out or demand exorbitant
compensation if she does not want to give up her entitlement. The assignment
of the entitlement thus inhibits greater use of solar collectors44
One state, Iowa, assigns the initial entitlement in solar easements in a way
that avoids at least some transaction coStS.45 Like other states, Iowa allows
users to create solar easements voluntarily.46 When a potential obstructer
holds out, however, Iowa authorizes local regulatory boards to create
easements without the burdened landowner's consent, provided that the
burdened landowner receives just eompensation.A7 Local legislative bodies
may establish "solar access regulatory boards" which govern applications for
solar casements41 An applicant must submit a statement of need, the legal
description of the estates, a description of the solar collector,an explanation of
the application's reasonableness, and a statement that the applicant has
attempted to negotiate an easement 49 The law requires the review board to
grant compensation for burdened property owners "based on the difference
between the fair market value of the property prior to and after granting the
solar access easement."50 Anecdotally, the statute has encouraged voluntary
4' Eisenstadt,supra note 2,at 25;Gevurtz,supra note 13,at 115.
42 See, e.g.,Polis,supra note 40, at 364 ("The Colorado statute, by requiring that the
right be bought,in effect grants the entitlement of solar access to the potential obstructor,
who is allowed to establish the cost."),
43 See ALAN S. MILLER ET AL., SOLAR ACCESS AND LAND USE: STATE OF THE LAW 4
(1977)(describing the windfall received by an owner of burdened property as unjustified).
44 Goble,supra nate 16,at 103 ("[T]he current assignment of the right is not conducive
to the use of solar energy. While economic theory suggests that the initial assignment of a
property interest will have no effect on resource allocation if the right is freely transferable,
the theory assumes that transactions are costless. In fact, transaction costs are often
substantial.").
45 See IOWA CODE ANN.§564A.7.1 (West 1992)("Persons,including public bodies,may
voluntarily agree to create a solar access easement.").
46 See id. §564A.7.
41 It/ §§ 564A.1-.9(summarizing the procedures to obtain access to solar energy). The
"just compensation"requirement attempts to avoid challenges under the Takings Clause of
the Constitution.
48 Id.§§564A.2(7),.3.
49 Id.§564A.4(describing these and other requirements of the application).
50 Id §564A.5(3).
20091 SOLAR RIGHTS 1231
agreements 51 The Iowa approach reflects a sensible statutory solution to the
holdout problem.52
B. Cotenants
In certain circumstances, covenants, a second type of express agreement,
avoid the difficulties of express easements in promoting solar rights. Like
express easements, covenants include conditions that run with the land and
endure indefinitely.53 Covenant conditions range widely in substance and may
involve usage, characteristics of future purchasers,building configuration, site
planning, aesthetic regulations, noise rules, and financial assessments, among
other things. A covenant must be recorded on the land records in sufficient
detail to provide notice of the existence and substance of the covenant. The
recording and notice requirement allows the cost or benefit of the covenant to
be incorporated into the purchase price of a parcel.54 In this sense, covenants
are efficient; purchasers with knowledge implicitly agree to incorporate the
terms of the covenant in their purchase. Covenants also appear to be fair,
because they often burden or benefit the owners of multiple parcels in the same
way, with the same provisions applied to parcels in a geographically
contiguous area,and because purchasers take land with notice of the covenant.
The right to enforce(or the standing to overturn) covenants is shared between
the owner of a covenanted property, other property owners burdened or
benefited by the same covenant, and subsequent purchasers.55 Covenants
appear most often, and fimction best, in residential neighborhoods with
relatively homogenous lot sizes and structure types 56
51 Potis,supra note 11,at 142 n,130.
52 Gergacz,supra note 30,at 30(calling the Iowa statute a"grant of eminent domain to
individual solar energy users . . . [which nonetheless] seems to be . . . equitable and
workable").
53 BLACK'S LAw DICTIONARY,sip'a note 25,at 421.
W See John William Gergacz, Solar Energy Law Easements of Access to Sunlight, 10
N.M.L.REV. 121, 136(1979-1980)(highlighting the importance of the legal description of
the parcel by saying that"[c]areful drafting would be required if the solar access rights were
created either by express covenant or by express easement").
55 Berryhill &Parcell,sopa note 6,at 438;Debra L. Stangl,Comment,Assuring Legal
Access to Solar Ene)gy:An Overview with Proposed Legislation for the State ofNebraslra,
12 CREIGHTON L.REV.567,609(1978-1979). Note that casement rights,by contrast,vest in
only the servient and dominant owners.
" Berryhill & Parcell, saga note 6, at 439 (commenting on covenants' "limited
applicability to established neighborhoods and commercially and industrially developed
land where structures are not of uniform size and height");Jesse L.Mamson,A Legislative
Approach to Solar Access: Transferable Development Rights, 13 NEN ENG.L. REV. 835,
846(1978)(criticizing restrictive covenants as being unhelpful in established neighborhoods
and commercial and industrial areas).
1232 BOSTON LWVERSITYLAWREVIEW [Vol. 89:1217
Some critics have called covenants a"two-edged sword because they can be
used to either inhibit or enhance the use of solar systems."S7 Covenants may
limit building and tree heights, govern the use of certain technologies, and
mandate aesthetic guidelines. Depending on the specific requirement, each
condition could either facilitate or hinder the use of solar collectors S8 A
developer may inadvertently thwart the installation of solar collectors by
creating a covenant with financial gain, not solar access, in mind.59 For
example, she may ask her attorney to draft a covenant that prohibits the
installation of"equipment"on rooftops. In the developer's mind,this covenant
would ensure it uniform aesthetic and thereby preserve or enhance property
values. For the potential solar user, however, the covenant precludes (or at
least renders ambiguous)the possibility of locating a solar collector on the roof
— often the most practical location for a collector. Litigation to clarify the
covenant would be costly and inconvenient, and a property owner may simply
avoid the installation of the solar collector altogether.60
To avoid such scenarios, some states have begun to legislate for covenants
that promote, rather than hinder, solar collector use. Although coots will
enforce covenants for solar access even if legislatures do not specifically
authorize them,61 several states have made their authorization explicit 6z At
least a dozen states go further,voiding restrictive covenants or deed conditions
if they unreasonably restrict or increase the cost of a solar system 61 Three
n Eisenstadt,supra note 2,at 26(mentioning that many developments with architectural
review boards reject solar access because of aesthetic concerns). See also Mattison,supra
note 56, at 846 ("Restrictive covenants are excellent tools to secure access in new
developments.").
51 See Berryhill &Parcell,supra note 6, at 438 (describing covenants which facilitate
solar use as "resuict[ing] the height and placement of structures and trees so as to avoid
blocking of solar collectors ofusers within the subdivision");Eisenstadt,supra note 2,at 26.
" Eisenstadt, supra note 2, at 27 ("[T]he developer exercises his own discretion in
deciding whether to impose such covenants,").
" See Kmye v. Old Orchard Ass'n, No. C 209 453 (Cal. Super. Ct., Feb. 28, 1979)
(reported in Current Developments, 1 SmAaL.REP. 3,8(1979))(considering this question
and relying on a state statute to find in Favor of the solar user).
61 Gergacz,supra note 54,at 133-34.
b2 See, e.g.,MD.CODE ANN,REAL,PROP. §2-118(7)(LexisNexis 2003)(authorizing the
creation of covenants which relate to the "[p]reservation of exposure of solar energy
devices");NEB.REV.STAT. §66-909(2003)(defining"solar skyspace easement"to include
covenants);N.H.REV.STAT.Arm. §§477:49-:50(2001); R.I.GEN.LAWS §§ 34-40-1 to-2
(1995); UTAH CODE: ANN. §§ 57-13-1 to -2 (2000); WASH. REV. CODE ANN. §
64.04.150(I)(b)(West 2005).
63 Aarz.REV.STAT.ANN. §33-439A(2007);CAL.CIV.CODE.§714(a)-(b)(West 2007&
Supp. 2009) (voiding "[a]ny covenant, restriction, or condition contained in any deed,
contract, security instrument, or other instrument affecting the transfer or sale of, or any
interest in,real property that effectively prohibits or restricts the installation or use of a solar
energy system"unless such restrictions"do not significantly increase the cost of the system
2009] SOLAR RIGHTS 1233
states have created special rules for condominiums or homeowners'
associations, prohibiting certain restrictions on solar collectors G4 One state,
Iowa, does not itself ban, but instead empowers localities to ban, covenants
with unreasonable restrictions on solar collectors.65 Although one
or significantly decrease its efficiency or specified performance, or . . . allow for an
alternative system of comparable cost, efficiency, and energy conservation benefits');
Coto. REV. STAT. § 38-30-168(1) to -(2) (2008) (excepting restrictions that constitute
"[a]esthetic provisions that impose reasonable restrictions on the dimensions,placement,or
external appearance of a renewable energy generation device and that do not (I)
Significantly increase the cost of the device;or(II)Significantly decrease its performance or
efficiency"); FLA. STAT. ANN. § 163.04(2) (West 2006 & Supp. 2009);HAW.REV. STAT.
ANN. § 196-7(a) (LexisNexis 2008) (stating that "no person shall be prevented by any
covenant, declaration, bylaws, restriction, deed, lease, term, provision, condition, codicil,
contract, or similar binding agreement . . . from installing a solar energy device" on a
"residential dwelling or townhouse"owned by the person);MD.CODE ANN.,REAL PROP. §
2-119(LexisNexis 2003);MASS.GEN,LAws ANN. eh. 184,§23C(West 2003);NEV.REV.
S'rivr. § 111.239 (2007) (calling any prohibition or unreasonable restriction on solar
collectors"void and unenforceable");id. §278.0208;N.M.STAT.ANN. §3-18-32(B)(West,
Westlaw through laws effective Apr. 10, 2009);N.C. GEN.STAT. § 22B-20(b), (d)(2007)
(calling"any deed restriction,covenant,or similar binding agreement that runs with the land
that would prohibit,or have the effect of prohibiting,the installation of a solar collector. . .
void and unenforceable,"except those which restrict solar collectors from public view);OR.
Rev.STAT.ANN.§ 105.880(1)(West 2003)("No person conveying or contracting to convey
fee title to real property shall include in an instrument for such purpose a provision
prohibiting the rise of solar energy systems by any person on that property."); Wis.STAT.
ANN. § 236.292(2) (West 2009) ("All restrictions on platted land that prevent or unduly
restrict the construction and operation of solar energy systems . . . are void."); see also
Kraye,No. C 209 453 (reported in Current Developments, I SOLAR L.REP. 3, 8 (1979))
(relying on the policy goals of California Solar Rights Act to find that a covenant which
prohibited appliances on rooftops that would be visible from neighboring streets could not
prevent a property owner burdened by such covenant from installing solar panels).
fi4 HAw. REV. STAT. Arm. § 196-7(b) (LexisNexis 2008) (providing that condo or
homeowners associations "shall facilitate the placement of solar energy devices and shall
not unduly or unreasonably restrict that placement so as to render the device more than
twenty-five per cent less efficient or to increase the cost of the device by more than fifteen
per cent"and prohibiting such associations from charging home owners any fees for such
devices); N.J. STAT. ANN. § 45:22A-48.2(a) (West Supp. 2008) (stating that "[a]n
association formed for the management of commonly-owned elements and facilities . . .
shall not adopt or enforce a restriction, covenant,bylaw,rule or regulation prohibiting the
installation of solar collectors on certain roofs of dwelling units"); VA.Conn,Arm. § 67-
701.A.to B.(2007&Sapp.2008)(stating that"no community association shall prohibit an
owner from installing or using a solar energy collection device on that owner's property"
except in common areas of the community,under certain conditions).
65 IOWA CODE Arun. §564A.8(West 1992)(allowing localities to"include in ordinances
relating to subdivisions a provision prohibiting deeds for property located in new
subdivisions from containing restrictive covenants that include unreasonable restrictions on
the use of solar collectors").
1234 BOSTON UNIVERSITYLA W REVIEW [Vol. 89:1217
commentator has raised the issue of constitutional challenges to statutes
voiding covenants that hinder solar collectors, no court has found, nor is one
likely to find,such statutes unconstitutional G6
The biggest barrier to covenants that promote solar collectors is not legality,
but practicality. Covenants are extremely difficult to impose retroactively on
parcels in established neighborhoods, and therefore may only be practically
useful in creating solar rights in new subdivisions.G7 To impose a covenant on
a new subdivision, a developer simply appends the covenant to the deed of
each new parcel 6s Each buyer must incorporate the financial impact of the
covenants into her purchase decision but need not do more. Covenants in new
subdivisions therefore usually have low transaction costs. It is important to
note that,although in theory the enactment of covenants in new subdivisions is
easy, developers do not typically protect solar access voluntarily.69
Accordingly, several states have either allowed or required localities to
consider solar access concerns when adopting subdivision regulations or
approving subdivision requests from developers 70 When evaluated as a legal
66 Joel S.Goldman,Constitutionalio,ofSection 714 of the Califonda Solar Rights Act,9
EcoLoor L.Q.379,391-404(1981)(focusing on CAL.CIV.CODE§714(West Supp. 1980)
and arguing that a takings challenge would fail because the public benefit of the law is
substantial and the potential harm to the individual property owner is slight,but questioning
the constitutionality of the law under the contract clause, which prohibits states from
impairing contracts).
67 See Berryhill&Parcell,supra note 6,at 439("Obviously,the use of covenants shows
most promise in new developments where potential buyers would be attracted to the
homogeneity of a solar neighborhood."); Bradbrook, supra note 27, at 238 (commenting
that "as a practical matter, with the sole exception of restrictive covenants in new land
subdivisions, the common law does not provide any effective safeguards for solar . . .
access");Eisenstadt,supra note 2,at 28.
" See MILLER Er AL., supra note 43, at 12 ("[T]Irey should be routinely used in
subdivision, mall, or industrial park situations. They cost nothing, and do not require
unsophisticated individual property owners to draw up legal documents. The developer's
lawyer has only to add a clause or two to the deeds.").
69 Likely, developers fail to do so because either they do not know that solar access
covenants exist, or they believe that solar access covenants may decrease the value of the
property being sold.
70 See, e.g., CoLo. REv. STAT. §§ 30-28-133(4.5), 31-23-214(2.5) (2008) (allowing
subdivision regulations adopted by a board of county cotmnissioners or by planning
commissions or cities and towns,respectively,to provide for the protection and assurance of
"access to sunlight for solar energy devices by considering in subdivision development
plans the use of restrictive covenants or solar easements, height restrictions,side yard and
setback requirements,street orientation and width requirements, or other permissible forms
of land use controls"); CONN. GEN. STAT. ANN. § 8-25(b) (West 2001 & Supp. 2009)
(stating that subdivision regulations "shall also encourage energy-efficient patterns of
development and land use,the use of solar and other renewable forms of energy,and energy
conservation"); ME.REv.STAT.Arm. tit. 30-A, § 4405 (1996) ("The municipal reviewing
authority may, to protect and ensure access to direct sunlight for solar energy systems,
2009] SOLAR RIGHTS 1235
tool with the potential to create solar rights,such statutes have the same flaw as
covenants — they apply prospectively only to those large-scale transactions
which require subdivision review.71
While enacting covenants in new subdivisions is relatively easy, enacting
covenants in established neighborhoods requires significant involvement by
individual parcel owners, some of whom may not want to permanently burden
their properties for the sake of solar rights. Like an express easement, which
requires a legal document separate from the deed that a property owner obtains
upon transfer,a retroactive covenant requires an entirely new agreement. That
agreement must address existing conditions (such as irregular lot sizes or
unusually shaped structures), duration and termination issues, the substantive
nature of the covenant, and any required financial exchanges. Special
provisions may be made for parcels on the fringes of the geographic area that
the proposed covenant may burden, because fringe parcels will abut
prohibit,restrict or control development through subdivision regulations. The regulations
may call for subdivision development plans containing restrictive covenants, height
restrictions, side yard and set-back requirements or other permissible forms of land use
controls."); MASS. Geta. LAws Amo. ch. 41, § 81M (West 2004) (indicating that local
boards'"powers may also be exercised with due regard for the policy of the commonwealth
to encourage the use of solar energy and protect the access to direct sunlight of solar energy
systems");MINN.STAT.ANN.§462.358(2a)(West 2008&Supp.2008)(allowing municipal
subdivision authorities to consider solar access and adding that subdivision `regulations
may prohibit, restrict or control development for the purpose of protecting and assuring
access to direct sunlight for solar energy systems");OR.REV.STAT.Arms. §92.044(1)(a)(C)
(West 2003&Supp.2008)(providing that localities establish standards for subdivision plats
which provide "adequate light and air including protection and assurance of access to
incident solar radiation for potential future use");UTAH Cone ANN. § 10-9a-610(2008);id.
§ 17-27a-610(2005)(allowing municipalities and counties,respectively,to refuse to renew
or approve subdivision plans or street dedications"if deed restrictions,covenants,or similar
binding agreements running with the land for the lots or parcels covered by the plat or
subdivision prohibit or have the effect of prohibiting reasonably sited and designed solar
collectors"); VA. CODE ANN. § 15.2-2242.6 (2008) (`Provisions for establishing and
maintaining access to solar energy to encourage the use of solar heating and cooling devices
in new subdivisions. The provisions shall be applicable to a new subdivision only when so
requested by the subdivider.");Wis.STAT.ANN. §236.13(2)(d)(West 2009)("As a further
condition of approval, any county, town, city or village may require the dedication of
easements by the subdivider for the purpose of assuring the unobstructed flow of solar or
wind energy across adjacent lots in the subdivision."). Localities, too, have enacted
subdivision rates which prioritize solar design. See, e.g., BREA CITY, CAL., Cone §
18.84.010, available at http://www.amlegal.com/nxt/gateway.dlt?f—teinplates&fi>=
default.htm&vid=amlegahca;ALBUQUERQUE,N.M.,ORDINANCES§ 14-14-4-2(B),available
of httpsvww.anlegal.com/nxt/gateway.dll/New%2OMexico/albugwin/cityofalbuquergtie
newmexicocodeofordinance?f=templates$fn=defatilt.htm$3.0$vid=amtegal:Albuquerque_it
in me(requiring that streets be oriented to facilitate solar access).
11 Some commentators are optimistic about the ability of subdivision regulations to
create solar rights. See, e.g.,HAYES,supra note 3,at 125("It may be easier,politically,to
change subdivision regulations rather than to change zoning.").
1236 BOSTON UNIVERSITYLAWREVIEW [Vol. 89:1217
unburdened properties.72 Even if the property owners involved in a potential
solar covenant could agree on all of the variables,the costs of bargaining for a
covenant may equal or even exceed the transaction costs of express
easementsP Requirements for covenants may actually raise the cost of
construction while simultaneously dampening property values. For these
reasons,covenants—like express casements—show little promise in protecting
solar rights, with the minor possible exception of the new residential
subdivision.74
C. Tenancy
Lessor-lessee arrangements, a third kind of express agreement that could
create solar rights, suffer from some of the same deficiencies as express
easements and covenants. Leases provide the barest of property interests.
They merely allow a lessee the temporary right to occupy a parcel.75 To give
rise to a solar right, a lease must govern some unit of property through which
the sun's rays must travel.76 Typically, solar leases involve airspace, known
sometimes in the solar context as solar skyspaces.77 Airspace has long been
recognized at cornmon law as real property and may be legally distinct from
ground or mineral estatesJs An individual who owns a piece of property in fee
simple may sever the airspace from the ground parcel or craft a legal
description which enables her to lease or burden just the airspace, without
severance. A lease would give a solar user the ability to"occupy"the airspace
without obstruction. Some states have tolerated leases that aim to provide
72 See Bradbrook,supra note 27,at 237.
73 See Gergacz,supra note 54,at 135.
14 Bradbrook, supra note 27, at 261 (asserting that "[]legislation permitting and
encouraging the use of solar. . .easements or covenants are not by themselves an adequate
form of solar...access protection").
75 BLACK'S LAW DICTIONARY,supra note 25,at 970.
76 Of course,many kinds of teases may implicate solar rights. For example,some leases
may prohibit the installation of solar collectors — an issue at least one state has tried to
address. See HAW, REV. STAT. ANN. § 196-7(a) (LexisNexis 2008) (rendering void and
unenforceable leases which prohibit a person from installing a solar energy device on a
residential dwelling or townhouse he or she owns). In another example, some interesting
legal wrinkles may arise when individuals lease space on which to place solar collectors or
attendant equipment. For the purposes of this Article,however,the key question is whether
the lease as a form can create solar rights which would stimulate the use of solar collectors,
and this question is best addressed by discussing only those leases which involve solar
skyspace required for solar access.
77 A solar skyspace is the space between a solar collector and the sun,which must remain
unobstructed for the solar collector to £auction properly. See, e.g.,NEB.REV.STAT. § 66-
907(2003);R.I.GEN.LAws§34-40-1(2)(1995).
7s See Janice Yeary, Energy: Encouraging the Use of Solar Energy — A Needs
Assessment for Oklahoma,36 OKLA,L.REv. 136,141 (1983).
20091 SOLAR RIGHTS 1237
solar access within existing landlord-tenant ]aw.79 Only one state, Nebraska,
explicitly recognizes leases for solar skyspaces and requires that such leases be
in writing and recorded on the land records 80
Most states, however, do not require such formalities for leases. People
enter into leases far more frequently than they create easements and covenants.
In non-complex transactions, leases involve only two parties, attorneys rarely
participate, and negotiation may be minimal. Accordingly, of the three types
of express agreements considered in Part II, leases may have, on average, the
lowest transaction costs. Many leases,however,are ultimately inefficient with
respect to solar rights,because the duration of a tenancy limits the duration of
the right. A lease of solar skyspace for utilizing a solar collector is most
efficient if the tenancy endures beyond the payback period of the collector and
if the lessee has some assurance that the lessor will not revoke the lease. If a
proposed lease tern is too short, or the lessor's termination provisions too
liberal, a potential lessee may not want to invest in a solar collector. Despite
their low transaction costs, leases may be an impractical means of truly
protecting solar rights.
III. GOVERNMENTAL ALLOCATIONS
Governmental allocations — public decisions, whether administrative or
legislative, made in accordance with established procedures — provide
alternatives to the express agreements between private parties described in Part
II. This Part analyzes the implications existing state and local decision-making
has on solar rights via the legal mechanisms of permit systems and zoning
ordinances. Several states and localities have experimented with permit
systems that allocate solar rights based on criteria analogous to the prior
appropriation regime or reasonable use requirements in water law. Where
permit systems exist,the initial entitlement, by default, rests with parties who
may be burdened by a solar right; solar rights seekers must apply to change the
default. While permit systems assume a baseline without solar rights, solar
zoning ordinances set solar rights as the baseline. A few localities have crafted
zoning ordinances — some influenced by state legislation— which respond to
solar concerns. In these jurisdictions, depending on the ordinance, the initial
entitlement may belong to property owners who could use and benefit firm
solar rights, not potential obstructers. In jurisdictions with traditional zoning
codes(that is,codes that do not account for solar rights),the opposite is true.
Each of the two systems considered in Part III provides individuals
petitioning for solar rights with different procedural opportunities to obtain
such rights. Public decisions have few transaction costs in some senses,for the
rules as written are uniform; decisions are made within time limits established
i9 In California, for example, investors have been entering(in alarming numbers) into
leases for desert land that is intended to be used as solar energy sites, although these are
leases of land and not leases of solar rights. Woody,supra note 19.
B0 NEB.REV.STAT.§66-911.01.
1238 BOSTON UNIVERSITYLA W REVIEW [Vol. 89:1217
by law; and one public body oversees each petition. However,when the rules
are applied, transaction costs rise because each petitioner must go through an
individualized review process, and the outcome is often uncertain. In addition,
sometimes public decision-makers may not always get it right: that is, the
govermncntal allocation does not necessarily allocate the costs of a decision to
those who benefit or properly compensate those who lose, rendering the
allocation inefficient.
A. Permits
Permits exemplify the benefits and flaws of governmental allocation of solar
rights. To issue a permit, a state or local government agency must evaluate
applications on a case-by-case basis while at the same time striving for
consistency across decisions. A permit system might require several steps: a
potential solar user must submit an application;neighbors roust be notified and
be given time to object and be heard; the relevant level of government must
rule to grant or reject the permit;and,if issued,the permit must be registered."
Applications must generally include descriptions of the real property on which
the solar collector was located, dimensions needed for solar access over real
property which would be affected by the right, and present and future growth
or strictures which might interfere with the solar right"
In the three states —New Mexico, Wyoming, Wisconsin — and the handful
of cities where solar permit systems have been most fiilly realized, permit
applications generally follow this pattern.83 New Mexico and Wyoming use a
prior appropriation(first in time,first in right)approach similar to the approach
sometimes used in water law 14 Both states allow the applicant-owner of a
solar collector to attain rights to solar access if the owner used the collector
8t Bradbrook,supra note 18,at 186; Eisenstadt,supra note 2, at 31. In Wisconsin, for
example, a locality can"provide by ordinance that a fee be charged to cover the costs of
processing applications." WIS. STAT. ANN. § 66.0403(2) (West 2003 & Supp. 2008).
Notice must be provided to property owners who may be affected by the granting of the
permit,and such property owners can request a hearing within thirty days of receiving the
notice. Id.§66.0403(3)-(4),
82 Lungren,supra note I,at 195(proposing a model statute for solar permits whose basic
tenets are reflected in existing state and local statutes). The model statute also requires that
landowners who might be affected by the creation of the right be notified and provided with
the opportunity to schedule a hearing if they object to the granting of a permit. Id. at 195-
96.
63 Note that Wisconsin and Wyoming delegate the permitting function to local
governments. WIS.STAT.ANN.§66.0403;Wyo.STAT'.ANN.§34-22-105(b)(2007).
84 The New Mexico stature differs from traditional prior appropriation rates with respect
to the substantive meanings of beneficial use,prior appropriation,and transferability, See
Karin Hillhouse&William Hillhouse,New Mexico's Solar Rights Act:A Claud over Solar
Rights, 1 SOLAR L.REP. 751, 754 (1979) (lamenting that New Mexico's attempt to apply
water law doctrine to solar energy confuses rather than clarifies solar rights issues).
20091 SOLAR RIGHTS 1239
before other uses that may block out such light, and if that use is beneficial.85
Successful applicants do not"own"the sunlight,but have it fight to divert it for
a beneficial use.86 According to the Wyoming statute, solar collectors are
protected only between nine a.m. and three p.m., because outside of those
times the benefit to the solar collector owner "is de minimis and may be
infringed without compensation," and no protection is given to collectors
"which would be shaded by a ten(10)foot wall located on the property line on
a winter solstice day."87 Once obtained,solar permits in both states,like water
permits received through prior appropriation regimes,are freely transferable.88
Wisconsin takes a different approach;it incorporates the reasonable use rule
on private nuisance from the Restatement (Second) of Torts into the solar
permit statute.89 The municipal agency which adirrmsters solar permits can
only grant a permit if doing so would not unreasonably interfere with
development plans,if no person has made substantial progress toward building
a structure which would create an impermissible interference, and if the
benefits to the public (including the applicant) will exceed the burdens of the
grant." This weighing of the benefits and burdens on parties with competing
interests reflects an approach grounded in nuisance law. The law allows
permit holders to sue neighbors who interfere with the solar access granted by
85 N.M. STAT. Arm. §§ 47-3-1 to -5 (West, Westlaw through laws effective Apr. 10,
2009);Wro.STAT'.ANN.§34-22-103.
e6 Deborah S. Grout, Access to Sunlight: New Mexico's Solar Rights Act, 19 NAT.
RHSOURCES J.957,958(1979)("Just as the owner of a water right does not'own'water but
rather has a right to divert it and put it to a beneficial use,so the owner of a solar right does
not own sunlight but has the right to [use it,provided that it is] put to a beneficial use."
(footnote omitted)). Neither statute ranks uses to indicate which use would be most
beneficial. See Hillhouse&Hillhouse,supra note 84,at 756(identifying this problem with
respect to the New Mexico law).
81 Wyo.SrAT.ANN.§34-22-104.
88 N.M. STAT. ANN. § 47-3-4.B(3) (calling such rights "freely transferable within the
bounds of[the law]"); WYO.STAT.ANN. § 34-22-103. The transferability concept differs
here from that concept in water law, as water rights can be transferred from person to
person,while solar rights can only be transferred to subsequent owners of the parcel which
is the subject of the right.
A9 Laurie Bennett,Recent Developments:Pmh v.Maretti, 108 Wis. 2d 223, 321 N.YY.2d
182(1982), 14 ENvrc. L.223,226(1983)(describing the Restatement(Second)of Torts's
analysis of private nuisance, which would find unreasonable any intentional invasion in
which the gravity of the harm outweighs the utility of the defendant's conduct). Cf.
Lungren,supra note 1,at 196-97(proposing a model statute rooted in nuisance law,which
would grant a permit if doing so would not unreasonably interfere with orderly development
plans and if the benefit to the public outweighs the burdens placed on individual
landowners).
90 WIS. STAT. Arm. § 66.0403(5) (West 2003 & Stipp. 2008). See also id §
66.0403(6)(b)(requiring the applicant to record the permit with the register of deeds).
1240 BOSTON UNIVERSITYLA W REVIEW [Vol. 89:1217
the permit,whether through vegetation or through construction,with remedies
ranging from an injunction,to trimming vegetation,to damages91
Cities have created unique permitting regimes as well. Portland,Oregon has
a solar collector permit system that exempts existing vegetation and solar
friendly trees92 The city of Ashland, Oregon, uses a system of solar access
permits to protect solar collectors from shading by vegetation, but not from
shading by buildings 93 Boulder,Colorado has established a permit system that
protects existing or proposed solar collectors firm being shaded by new
construction or by vegetation.94 All of these municipal permits, like their state
counterparts,create novel property fights for solar access.95
The public creation of such property rights through permits has several
significant flaws. As with other governmental allocations, permit systems
require costly new bureaucracies, sometimes at both the state and municipal
levels91 In addition, they require individualized applications, the submission
and review of which impose high costs on government, the applicant, and any
affected third partics97 Despite creating a time-consuming review process,the
outcomes in permit decisions may not satisfy all of the affected parties,leading
to claims that the permitting system is unfair. Moreover,because outcomes are
unpredictable, benefited and burdened landowners may decline to enter into
express agreements, such as the ones described in Part I,which would obviate
91 Id §66.0403(7).
92 PORTLAND, OR., CITY CODE & CHARTER § 3.111.050 (2009), available at
http://wwtv.portlandonline.com/Auditor/index.cfm?c=28472#cid_15192.
93 ASHLAND, OR., Mon. CODE § 18.70.070 (2008), available at
http://www.asliland.or.us/Code.asp?CodclD=3338 (follow "18.70.070" hyperlink)
(indicating that shading by buildings is addressed separately by the setback provisions of the
ordinance); see also Swensen et al., supra note 30, at 9 (stating that in Ashland, "while
property owners do not need to be proactive to obtain protection from shade caused by
structures [because of zoning setback and height rules], they do need to take action to
protect their solar collecting devices from shade produced by vegetation').
94 CITY OF BOULDER, SOLAR ACCESS GUIDE OR SOLAR SHADOW ANALYSIS 1 (2006),
available at hip://Nvwww.bouldercolorado.gov/files/PDS/codes/solrshad.pdf (requiring that
building permit applicants submit a shadow analysis showing that their proposed
construction will shade adjacent lots no more than a hypothetical solar fence). Solar access
permits are available for owners of properties not in Solar Access Areas(where certain per
se protections already exist). Id. (clarifying that solar access permits are available to
homeowners whose planned solar systems "need more protection than is provided
automatically in Solar Access Areas I and IP').
9s See, e.g.,N.M.STAT.ANN. §47-3-4(A) (West,Westlaw through laws effective Apr.
10,2009)(declaring"that the right to rise the natural resource of solar energy is a property
right"); WYO. STAT. ANN. § 34-22-103 (2007) ("The beneficial use of solar energy is a
property right."); Bradbrook, sapra note 18, at 170 ("[S]ome legislatures [like Wyoming
and New Mexico] established the right of solar access as a separate, novel interest in
property.").
" See Bradbrook,supra note 18,at 189.
97 Eisenstadt,supra note 2,at 33.
i
2009] SOLAR RIGHTS 1241
the need for a permit 98 In the long term, property rights granted by permit
rmight not be recorded on the land records, which could prevent subsequent
purchasers (both benefited and burdened) from understanding their rights and
duties99
In addition to the administrative challenges created by a permit program,
many conarrentators have expressed concern that solar collector permits over-
protect energy uses and thwart real estate development.100 Historically,
American courts and legislatures resisted creating solar rights to avoid
impeding development.101 While any solar rights regime might impede
development, government-issued permits are more likely to impede
development on a wide scale than,say,express agreements between neighbors.
In an urban setting, a solar permit owned by one landowner might prevent
another landowner several blocks away from building a skyscraper that would
shade the permit holder's property. In such a situation, the builder of the
proposed skyscraper might petition the permitting agency for an exemption
from the obligations of the permit. The denial of the petition would effectively
prevent a skyscraper from being built; on the other hand, a grant of the
exemption would erode the value of the permit system as a whole by
introducing uncertainty into the entitlement process.
The would-be builder of the skyscraper,and others in similar situations,may
have grounds for a takings claim against the permitting agency. Indeed,
several scholars have argued that permit statutes, either as written or as
applied, unconstitutionally take the property of burdened landowners.102 A
i
98 Bradbrook,supra note 18, at 189 (observing that a permit system"vests substantial
discretion in the local council, which means that difficulty arises in predicting the likely
outcome of disputes. This discourages neighbors from reaching compromise settlements
and leads to protracted hearings.").
99 Cf. Eisenstadt, supa note 2, at 33 (identifying as a separate problem that "[t]he
volume of easements contained in property records might hinder title searches by title
insurance companies").
100 Bradbrook,supra note 27, at 262-63 ("Under New Mexico law,the installation of a
small solar hot water system could by itself prevent a large commercial or industrial
development from occurring on neighboring land. In this way,the proper development of
towns and cities can be impeded."(footnote omitted)); Bradbrook,supra note 18, at 176;
Lungren,supra note 1,at 182;Polis,supra note 40,at 372("The statute appears,however,
to assume a preference of use for energy purposes[over other uses]...."). 1
"' Bradbrook,supra note 27,at 263. The New York Times offered this explanation for
the American rejection of solar rights back in 1878. See Ancient Lights,N.Y.TIMP.s,July 7,
1878,at 6("[C]ourts have rendered decisions that the law of ancient lights is inappropriate
and inapplicable in America . . . . Our sparsely-settled country, they say,has not required
such a law;encouragement of building is more needed than restrictions upon it,").
102 See, e.g.,Gergacz,supra note 30,at 17 ("The New Mexico statute probably crosses
the line into the unconstitutional arena. Since no limitation is placed upon the size or
location of the solar collector, the broad sweep of the protection given to the solar energy
user could well render useless the property of the adjoining landowner.");Grout,supra note
1242 BOSTON UNIVERSITYLAWREVIEW [Vol. 89:1217
takings challenge might succeed if a burdened property owner could prove that
the permit reduced her property's value in violation of established takings
precedent and that the government did not compensate her for this reduction."'
None of the permit schemes described here provide compensation for burdened
neighbors,at least in part because questions relating to compensation—how an
agency could determine the impact of a solar permit, which neighbors would
merit compensation, and who should disburse the compensation — are
inherently difficult to resolve.104 Nonetheless,the possibility of takings claims
presents a real challenge to the wide-scale enactment of solar permitting
systems.
B. Zoning
Like permit regimes, zoning ordinances require government decisions on
individual applications— decisions that may be criticized on several grounds.
Zoning refers to the regulation of uses, lot sizes, building characteristics, and
other site features through a local body that has been publicly elected or
appointed to uphold the map and text of the zoning ordinance.105 Localities
that choose to address solar access through the enactment and application of
their zoning ordinances must find grounds in state law. As a starting point,
they may rely on the authority granted by enabling statutes in every state,
which authorize them to provide for "safety, morals or general welfare" and
"adequate light and air."106 To make localities' authority more explicit,at least
86, at 959 (criticizing the New Mexico law as unconstitutional in certain cases where the
grant of the right could so diminish the value of the burdened neighboring property that the
grant would constitute a taking without just compensation); Stephen B. Johnson, State
Approaches to Solar Legislation:A Survey, 1 SOLAR L.Ree. 55, 121 (1979) ("The scheme
could be construed as a taking without compensation instead of a regulation if the
diminution in value is great enough, and if alternative uses are nonexistent"); Lungren,
supra note 1, at 182 (arguing that the absolute property right granted by New Mexico's
Solar Rights Act "diminishes the value of the neighbor's property without providing just
compensation").
103 The case most likely to be used to measure the skyscraper builder's takings
allegations is Penn Central Transportation Co. v. Nen, 1'wk 0% 438 U.S. 104 (1978),
which established a three-factor balancing test to weigh takings cases.
104 But see Bronin, supra note 10, at Part I1I.13 (proposing some guidelines for
compensating losing parties).
105 See BLACK'S LAw DicnONARY,sapra note 25,at 1757.
los See HAYES,supra note 3,at 74("The right of governments to impose zoning controls
has been widely upheld by courts for more than fitly years.");Eisenstadt,sapra note 2,at 40
(explaining that rules which involve solar access likely rely on "adequate light and air"
provisions in state enabling statutes); Osofsky, sapra note 32, at 647 ("Solar zoning
ordinances likely will be upheld by the courts if they demonstrate some tendency to serve
the public health,safety, morals or general welfare.");Phelps &Yoxall,supra note 30, at
153("Arguably,promotion of solar energy is a justifiable use of a municipality's judicially
recognized police power to zone for the `health, safety or general welfare of the
20091 SOLAR RIGHTS 1243
thirteen states authorize localities to zone for solar access.107 In addition,a few
states require that solar access be taken into account when designing zoning
community."' (citing NectoNv v. City of Cambridge, 277 U.S. 183 (1928) and Village of
Euclid v.Ambler Realty Co.,272 U.S.365(1926)for the proposition)).
107 ARIZ.REV.STAT.ANN.§9-462.01(A)(3)(2008&Supp.2008)(allowing localities to
regulate"access to incident solar energy");Coro.REV.SrA7.§31-23-301 (2008)(allowing
localities to establish height, setback, and density requirements for many purposes,
"including energy conservation and the promotion of solar energy utilization");CONN.GEN.
STAT. ANN. § 8-2(a) (West 2001) (allowing cities and towns to enact zoning regulations
which "encourage energy-efficient patterns of development, the use of solar and other
renewable forms of energy, and energy conservation" and "provide for incentives for
developers who use passive solar energy techniques"); IND. CODE ANN. §§ 36-7-2-2, -8
(West 2006) (allowing localities to "regulate access to incident solar energy for all -
categories of land use" and prohibiting the adoption of ordinances "prohibiting or . . .
unreasonably restricting the use of solar energy systems other than for the preservation or
protection of the public health and safety"); 10WA Conn, ANN. § 335.5 (West 2001)
(requiring that county governments' zoning regulations "be made in accordance with a
comprehensive plan and designed. . .to promote reasonable access to solar energy"); id. §
414.3 (West 2008) (requiring the same of city governments' zoning regulations); MINN,
STAT.ANN.§394.25(2)(West 1997 &Supp. 2008)(stating that localities could include in
zoning ordinances the"protection and encouragement of access to direct sunlight for solar
energy systems");id §462.357(1)(West 2008 & Supp. 2008)(allowing localities to zone
for"access to direct sunlight for solar energy systems");NEB.REV. S'rAT.§66-913(2003)
("All counties or municipalities having zoning or subdivision jurisdiction are hereby
authorized to include considerations for the encouragement of solar energy and wind energy
use and the protection of access to solar energy and wind energy in all applicable zoning
regulations or ordinances and comprehensive development plans");N.Y.GEN.CITY LAW§
20(24)(McKinney 2003);N.Y.TOWN LAW§263(McKinney 2004);N.Y.VrLr.AGE LAW§7-
704(McKinney 1996)(allowing cities,towns,and villages,respectively to regulate for"the
accommodation of solar energy systems and equipment and access to sunlight necessary
therefor");OR.REv. STAT.ANN. §§215.044,227.190(West 2009)(allowing city councils
and county governing bodies to adopt and implement solar access ordinances which take
into account"topography,microclimate,existing development,"and other factors,provided
that such ordinances do not eoti ict with comprehensive plans and land use regulations);id.
§ 227.290(2) ("The council may consider, in enacting ordinances governing building
setback lines, the site slope and tree cover of the land with regard to solar exposure.");
TENN. Cone ANN. § 13-7-101 (1999 & Supp. 2007) (allowing counties to consider
"[p]rotection and encouragement of access to sunlight for solar energy systems . . . in
promulgating zoning regulations"); WASH. REV, CODE ANN. § 36.70.560 (West 2003 &
Stipp.2009)(authorizing local planning bodies to enact"[s]pecific regulations and controls
pertaining to . . . the encouragement and protection of access to direct sunlight for solar
energy systems");Wis.STAT.ANN. §62.23(7)(c)(West 2000&Supp.2008)(granting town
councils the ability to draft zoning regulations which, among other things, "provide
adequate light and air,including access to sunlight for solar collectors");WYo.STAT.ANN.
§ 34-22-105(a)(2007)(allowing localities to regulate height, location,setback, and energy
efficiency of structures, height and location of vegetation, the platting and orientation of
land developments,and the type and location of energy systems).
1244 BOSTON UNIVERSITYLA W REVIEW [Vol. 89:1217
ordinances or comprehensive city plans,108 and various related initiatives have
become law.tog Several other states explicitly prohibit localities from passing
ordinances (zoning or otherwise) that would inhibit the operation of solar
collectors.110 These measures are a start. However, as has been argued
108 See, e.g.,Atuz.REV.STAT.ANN.§9-461.05(C)(1)(d)(2008&Supp.2008)(requiring
localities to consider "air quality and access to incident solar energy for all general
categories of land use"); CONN. GEN. STAT. ANN. § 8-23(c) (Wast 2001 & Supp. 2009)
(requiring that a planning and zoning commission develop a plan of conservation and
development which considers `the use of solar and other renewable forms of energy");
IOWA CODE ANN. § 335.5 (West 2001) (requiring that county governments' zoning
regulations"be made in accordance with a comprehensive plan and designed...to promote
reasonable access to solar energy"); id. § 414.3 (requiring the same of city governments'
zoning regulations); 53 PA. CONS. STAT. ANN. § 10604 (West Supp. 2008) (requiring
municipalities to design zoning ordinances which"promote,protect,and facilitate...access
to incident solar energy").
109 See, e.g., CAL.POB.RES.CODE. § 25982 (West 2007 & Supp.2009) (requiring that
solar collectors"be set back not less than five feet from the property line,and no less than
10 feet above the ground,"irrespective of any applicable zoning ordinance); 65 ILL.COMB.
STAT.ANN.5/11-12-5(5),11-13-1(West 2005&Supp.2008)(giving city plan commissions
the authority to recommend to municipalities "schemes for regulating or forbidding
stmetures or activities which may hinder access to solar energy" and allowing municipal
authorities`to regulate or forbid any structure or activity which may hinder access to solar
energy");NEB.REV.STAT.§66-914(2003)(authorizing zoning boards to grant variances if
the strict application of the zoning ordinance would restrict the use of solar energy systems,
as long as the variance was"without substantial detriment to the public good and without
substantially impairing the intent and purpose of such regulation or ordinance"); UTAH
CODE ANN. §§ 10-9a-401(2)(d) (2007), 17-27a-401 (2005) (allowing municipalities and
counties, respectively, to account for "the use of energy conservation and solar and
renewable energy resources"in their comprehensive plans);Wis.STAT.ANN. § 66.0401(2)
(West 2003) (providing that localities "may provide by ordinance for the trimming of
vegetation [which existed prior to the installation of a solar collector] that blocks solar
energy"and may include"a designation of responsibility for the costs of the trimming");id.
§ 700.41(2)-(3) (West 2001) (defining solar envelopes and providing that'the owner of a
solar energy system or a wind energy system is entitled to receive damages,court costs and
reasonable attorney fees"from anyone who builds beyond the solar envelope);see also id.. §
700.41(2)(a) (defining "building envelope" to mean `the 3-dimensional area on a lot on
which building is permitted, as defined by the existing ground level and by any applicable
height restriction,setback requirement,side yard requirement or rear yard requirement");id.
§ 700.41(2)(c)(1) (defining `obstruction" to mean "[t]he portion of a building or other
structure which blocks solar energy from a collector surface between the hours of 9 a.m.to 3
p.m.standard time if the portion of the building or structure is outside a building envelope in
effect on the date of the installation of the solar collector"(emphasis added)).
p0 CAL. GOVT CODE § 65850.5(a) (West Supp. 2009) (prohibiting localities from
creating`unreasonable barriers to the installation of solar energy systems,including,but not
limited to, design review for aesthetic purposes, and not unreasonably restrict[ing] the
ability of homeowners and agricultural and business concerns to install solar energy
systems"); IND. CODE ANN. § 36-7-2-8 (West 2006) (prohibiting local governments from
20091 SOLAR RIGHTS 1245
elsewhere, states should be more active in adopting regulations that advance
sustainable technologies, such as solar collectors, without infringing on local
autonomy."r The paucity of state laws relating to solar zoning confirms that
more could be done at the state level to encourage this method, however
flawed,of providing solar rights.
Whether solar zoning is specifically authorized, a zoning ordinance
establishes a baseline from which property owners may request it deviation.
Where authorized to do so, localities might zone to protect solar access in two
ways — one that builds on the existing baseline, and one that resets the
baseline. First, localities may allow solar rights seekers to obtain solar rights
through existing processes for variances, special exceptions, and other
flexibility rules common to zoning schemes across the United States.
Alternatively,in the map and text of the zoning ordinance, or in a special solar
zoning ordinance, localities may specify new "solar zones" which define how
property owners in such zones may establish solar rights, either as of right or
by individual petition."'
"adopt[ing]any ordinance which has the effect of prohibiting or of unreasonably restricting
the use of solar energy systems other than for the preservation or protection of the public
health and safety");N.M.STAT.ANN. §3-18-32(A)(West,Westlaw through laws effective
Apr. 10, 2009) ("A county or municipality shall not restrict the installation of a solar
collector as defined pursuant to the Solar Rights Act, except that placement of solar
collectors in historic districts may be regulated or restricted by a county or municipality");
Wis.SrA'r.ANN. § 66.0401(1) (West 2003)(`No county, city, town,or village may place
any restriction,either directly or in effect,on the installation or use of a solar energy system
unless the restriction. . . (a) Serves to preserve or protect the public health or safety. (b)
Does not significantly increase the cost of the system or significantly decrease its efficiency.
(o)Allows for an alternative system of comparable cost and efficiency.");WYO.STAT.Arm.
§ 34-22-105(c) (2007) (prohibiting localities from prohibiting the construction of solar
panels except for reasons of public health or safety).
See HAYES,sapra note 3, at 220 (suggesting that states "could require localities to
adopt such[solar access]ordinances and could specify standards the ordinances must meet;
[they]might also provide for state review of proposed ordinances and regulations');Sara C.
Holl n, The Quiet Revolution Revived: Sustainable Design,Land Use Regulation, and the
States,93 MINN.L.Ray.231,235,250-55(2008)(arguing for states to play a greater role in
land rise regulations affecting sustainable development, including solar access issues).
Zoning is,for now,an inherently local activity,and zoning decisions cannot be made at the
state level. See Stangl, supra note 55, at 622 ("[1]t would arguably be an unworkable
solution for a state legislature to devise an access scheme that would be applicable on a
state-wide basis.").
112 Several people have argued that a separate, specific solar ordinance is preferable to
incorporating solar access into the existing zoning code. See Osofsky,supra note 32,at 641
("Though conventional building height limitations, lot size restrictions, and set-back
requirements unintentionally aid the solar energy user, specific solar ordinances are still
preferable."); Zillman &Deeny,supra note 4, at 42-43 ("[B]uilding height limitations, lot
size restrictions,and set-back requirements. . . may be the functional equivalent of a solar
ordinance,but a specific ordinance is preferable.").
1246 BOSTON UNIVERSITYLA W REVIEW [Vol.89:1217
The first method for establishing solar rights in a zoning scheme requires
that a solar rights seeker follow established procedures to request specific relief
from the zoning ordinance.113 To receive a favorable ruling for a variance,
special exception, or other flexibility device from the zoning board, an
applicant must submit plans for proposed construction and indicate how such
plans comport with the zoning ordinance and,if applicable,the comprehensive
plan. Consider, for example, a situation in which a property owner seeks to
install a solar collector on her roof, but the zoning ordinance prohibits the
installation of "equipment" on roofs in the zone in which her property is
located. She may submit an application for a variance for her property,which
states that her property is exempt from the prohibition on equipment. The
review process may be lengthy and expensive, and the board's ultimate
decision may be at odds with either prior decisions or the ordinance itself.
Moreover, any right that she might receive through her petition would be
among the weakest of the solar rights described in this Article. If the zoning
board granted her the variance, she would not receive a right to solar access,
which is enforceable against others, but merely a right to establish access
without the ability to change others' behavior. In other words, her variance
would not allow her to prohibit a neighbor from erecting a skyscraper that
shades her solar collector. Nonetheless, the possibility of working within
existing rules to deviate from the baseline set by the zoning ordinance should
be noted as one path toward solar rights.114
The second possible means of protecting solar rights — drafting new,
comprehensive solar zoning provisions, or in other words, resetting the
baseline — better serves solar rights seekers because such provisions may
govern all properties within a neighborhood or neighborhoods, a situation
which renders solar rights enforceable (at least in part) against others."' At
their most basic, such solar zoning ordinances could limit heights, restrict lot
sizes, establish setback requirements (perhaps expanding setbacks for southern
exposures —the preferred orientation for solar collectors in this country), and
'" Another zoning alternative,not mentioned in this Article,is contract zoning,in which
the landowner and local government agree to special zoning rules in exchange for
landowner promises. At least two commentators have suggested that contract zoning could
"stimulate solar energy utilization." Phelps&Yoxall,supra note 30,at 151.
nJ Zoning ordinances often ban solar collectors. Berryhill &Parcell,saga note 6, at
441 (comneming that "[z]oning laws providing for aesthetic controls and structure
orientation may discourage or prohibit installation of solar equipment");Broom,supra note
111, at 249-55 (describing the ways in which local laws, including zoning ordinances,
thwart green building technologies such as solar collectors).
°5 As a practical matter,retroactive imposition of zoning presents challenges:"A zoning
ordinance typically would utilize height limitations and set back requirements to assure
unobstructed sunlight. This is impractical in areas already developed since structures cannot
be moved to meet new requirements for southerly set backs." Mattison,supra note 56, at
852.
20091 SOLAR RIGHTS 1247
create other rules that would facilitate solar access."' A more detailed
ordinance might create an overlay zone to the zoning map or otherwise
designate particular blocks as "solar blocks" and mandate solar access rights
for parcels within that block.' 7 Perhaps the most sophisticated solar zoning
ordinance in this country governs construction in Boulder, Colorado, which
has created a system of"solar envelopes" and "solar fences," each of which
function differently in different neighborhoods."' The solar envelope, similar
in concept to the solar skyspace,79 delineates a three-dimensional space over a
parcel beyond which no constriction or vegetation can occur without illegally j
interfering with the solar rights of neighbors.120 The solar fence represents a
vertical plane along a property line that casts an imaginary shadow that cannot
be exceeded in length by the shadows cast by any building or tree on the
neighboring property.121 The Boulder solar ordinance divides the city into
three zones, governed by area-wide rules establishing various solar envelope,
solar fence, and other requirements.12' Commentators have lauded the
envelope and fence elements of the Boulder system.123
Boulder notwithstanding, local government experiments with solar zoning
ordinances remain few and far between. Local governments may resist
16 See Osofsky,supra note 32,at 641.
°i See Polis, supra note 40, at 378, 385-87 (indicating that solar ordinances might
"designate a particular block or particular blocks for solar use"or might create mandatory
solar zones where the zoning board would disapprove construction "when the proposed
project would impede solar access rights"). .
1's See Crry of BOULDER,supra note 94,at 1.
119 See supra note 77 and accompanying text.
120 See OR.REV.STAT.ANN. § 105.885 (West 2003);Bradbrook,supra note 18,at 187;
Sampson & China, sapra note 38, at 430 (contrasting traditional zoning, which limits
construction to within a rectangular volume, to solar zoning, which creates a limiting
volume topped by multiple planes at angles defined by sun location).
121 See Bradbrook, supra note 18, at 187-88 (explaining that "[u]nder this system, no
building or tote maybe erected or planted on one block of land if it would cast a shadow on
neighboring land longer than the shadow that would be cast by an imaginary fence of a
designated height on the property boundary"at certain times of the year).
122 See, e.g.,BOULDER,COLO,REV. CODE § 9-9-17(d)(1) (1981)(barring persons from
erecting structures which would shade a protected area to a degree greater than the lot would
be shaded by a solar fence twelve feet in height for Solar Access Area I and twenty-five feet
in height for Area II,and requiring solar access permits for any protection in Area III);see
also Crry or BOULDER,supra note 94,at 1 (indicating the height of the solar fence in Solar
Access Areas I and it and describing the use of the fences for shadow analysis); Luke J.
Danielson,Drafting a Solar Access Ordinance: One City's Experience, 3 SOLAR L. REP.
911,936-37(1982)(describing in detail the solar fence concept in Boulder).
123 See, e.g.,KRAEtmrR,supra note 14,at 104(indicating that the solar fence"takes into
account topography,existing improvements and trees,and requires no complex or arbitrary
procedures");Osofsky,sapra note 32,at 637,642(defining solar or building envelopes and
calling"[slolar envelope zoning . . . a promising comprehensive and innovative approach
that local governments can use to guarantee solar access in residential areas").
1248 BOSTON UNIVERSITYLAWREVIEW [Vol. 89:1217
changing zoning ordinances because change requires money, time, expertise,
and political capital which local officials may be unwilling to spend.124
Despite slow progress, many scholars have argued that zoning represents a
critical part of the solution to the solar access dilemma. Because zoning occurs
at the local level, zoning officials can enable solar access in a manner that
responds to extant topography, vegetation, land uses, density, and building
types.125 Moreover,unlike a statewide solar permit system, which would have
to be created afresh,the boards, staff,and other administrative structures for a
solar zoning ordinance already exist.1�6 Decision-makers, whether elected or
appointed, must account for their actions to the public, which some believe
results in a proper balance between solar access and development.127 Unlike
some express agreements, all zoning decisions are public documents and,
especially if recorded on the land records,provide notice of solar access rights
to third parties.12' Finally, zoning, if properly crafted, will likely avoid
121 See, e.g.,Lydell,supra note 31,at 397-98; Phelps&Yoxall,supra note 30,at 161;
Comment, The Allocation of Sunlight:Solar Rights and the Prior Appropriation Doctrine,
47 U. COLO. L. REv. 421, 433-34 (1975-1976). But see Bersohn, saps note 6, at 141
("[R]ecent enactments on the state and municipal levels have set promising examples for
recognition of the open space and urban design requirements of solar energy use.").
12' See,e.g.,Bradbrook,supra note 27,at 266(concluding that based upon the Australian
experience,"too little emphasis has been given to the use of building,planning and zoning
laws as a suitable mechanism for achieving the desired goal");Bradbrook,supe note 18,at
185(arguing for greater reliance on planning law in solar access regimes,because"planning
law vests the majority of legal controls over land development in the hands of local
councils"and"solar access considerations are closely interrelated with important planning
issues concerning building height and setback requirements,block sizes and orientation,and
the orientation of streets");Eisenstadt,supra note 2, at 47 (indicating that zoning provides
flexibility and localization on a block-by-block basis and is a common and well understood
mechanism for land use planning); Lydell, strpra note 31, at 397 (indicating local
governments' expertise in "important considerations such as prevailing land use patterns,
the needs of the conmmunity,topography,and the height and bulk of buildings");Dwight C.
Seeley, Cmnment, Comparative Aspects of Access to Sunlight: The United States, Great
Britain, and Japan, 21 HARv. INT'n-L.J. 687, 705 (1980) ("Comprehensive solar zoning
would be relatively cheap to administer because the machinery already exists for zoning
decision-making.");Stangl,supra note 55,at 622("[I]t is precisely this kind of area-by-area
analysis that is imperative to widespread solar energy use and which makes zoning
particularly applicable to the solar access problem.").
126 See,e.g.,Stangl,supra note 55,at 622.
127 See,e.g.,Lydell,supe note 31,at 397.
12' Melvin A. Bedree,Recent Case, Ptah v. Maretti, 108 Wis. 2d 223, 321 N IV.2d 182
(1982),52 U.Cm.L.Rev.208,221 (1983)("[Ala the Proh dissent stated,control over solar
access through zoning would have the benefit of placing landowners on notice that a
particular neighbor has a solar access right.").
20091 SOLAR RIGHTS 1249
takings, equal protection, and due process challenges to which other systems
(such as permits)may be subject.129
Nonetheless, zoning presents concerns that cannot be overlooked. With
respect to transaction costs,zoning applications and submissions consume time
— with months required for appeals and public hearings, where applicable.
Applicants with difficult cases may find themselves mired in bureaucracy, the
navigation of which requires them to hire costly experts and attorneys.
Comprehensive ordinances that create building envelopes that enable the
passage of light by segregating structures on individual large lots may, in
effect,mandate sprawl. While individual property owners who receive a solar
right through a zoning ordinance benefit, other property owners must bear the
diffuse costs of sprawl —a far worse problem, arguably, than the low rate of
solar collector utilization."' Solar zoning should not rely on it large-lot
solation.
In addition to these problems,solar zoning may raise fairness concerns. The
text of a solar zoning ordinance may not account for variations in site
conditions across the properties under its jurisdiction. Solar envelopes, for
example, may be difficult to define on irregularly shaped parcels or in hilly
areas, a situation that may lead to unequal application of the rides.131
Enforcement may also be arbitrary when zoning boards modify their
interpretations of the zoning ordinance from case to case. in addition, the
failure to compensate burdened parties may create severe inequities among
landowners, and could also subject solar zoning ordinances to takings clause
challenges. No comprehensive solar ordinance provides compensation to
property owners who suffer from the ordinance's restrictions.132
Finally, zoning does not create a true vested property right.133 Even if
zoning ordinances change relatively infrequently,changes to the scope of solar
129 Eisenstadt,supra note 2,at 42(concluding"that the`taking'problem does not hinder
the validity of solar access zoning ordinances"). But see in. at 42-43 (discussing due
process concerns arising from solar zoning);Matuson,sapra note 56,at 852(contemplating
the potential for unconstitutional takings when solar zoning fails to"equitably balance the
competing interests of solar energy use and private property rights"); Phelps & Yoxall,
supra note 30,at 153-57(identifying takings,equal protection,and due process issues).
13o Matuson,supra note 56, at 852 (`Blanket zoning for solar access may conflict with
other energy conserving techniques such as compact and contiguous development...which
decreases the amount of fossil fuels needed to heat and cool structures for transportation.");
Phelps & Yoxall, supra note 30, at 151-52 (commenting that "large lot requirements
inherently lessen the possibility of shading conditions resulting from a neighbor's action").
131 See Bradbrook,supra note 18, at 189 (writing that with respect to solar envelopes,
"[(Ilrafting a suitable ordinance intelligible to the average person is extremely difficult").
O2 A suggested means of compensation, transferable development rights and has been
used by some cities as compensation for zoning or other land use restrictions. See Broom,
sapra note 10,at Part I11.13.
133 Goble,super note 16,at 122-23("While the landowner has the limited right that no
changes in the zoning regulations affecting his land be made unless required by the public
1250 BOSTON UNIVERSITYLAWREVIEW [Vol. 89:1217
rights in the ordinance which are not accompanied by an exemption for
nonconforming uses may mean that a property owner who used a solar
collector under a previous ordinance must dismantle or otherwise modify her
solar installation.1 ' Because it does not provide an enduring, secure property
right,zoning is among the least effective means of securing solar access.
PI. COURT ASSIGNMENTS OF RIGHTS
Because the governmental allocations described in Part III are deficient,
some solar rights seekers may turn to the courts. In theory, court decisions
result from carefid analysis of law and balancing of equities, and courts apply
precedent to adapt to new realities. Indeed, American courts have on
numerous occasions created legal rights to advance innovations with broad
social impacts.135 In 1946,for example,the Supreme Court accommodated the
advent of the airplane era by limiting property owners' rights to only the
airspace such owners could utilize.136 To have ruled otherwise, as Justice
Douglas pointed out,would have exposed airline companies to so many private
claims that travel by air would have been impossible.137 The Supreme Court's
creation of a travelway, for airplanes facilitated economic growth and
transformed the way we live. Similarly, the scarcity of land and the
proliferation of dense,high-rise condominium buildings gave rise to horizontal
airspace as a unit of real property—a concept in property law, which had not
existed before the advent of skyserapers.138 The property right in airspace
allowed property owners to maximize use of their land—much as a solar right
interest,this right falls far short of the vested property interest necessary to create a solar
right."); Lungren, sapra note 1, at 180 (explaining that"[z]oning provisions do not vest
rights in the property owner and are subject to change,often for political reasons");Daniel
P. Moskowitz, Legal Access to Light: The Solar Energy Imperative, 9 NAT. RESOURCES
LAW. 177,208(1976)(concluding that solar"access pursuant to a zoning ordinance will not
ripen into a prescriptive right"); Sampson & Charo, supra note 38, at 430 ("One
troublesome aspect of traditional zoning and the solar envelope is that the solar user
acquires no vested property right,").
134 But see HAVES, supra note 3, at 78 ("Municipalities frequently make substantial
revisions in their zoning laws. . . . It may be that if citizens perceive the changes to be in
their own interest,they will accept them even more readily.").
115 See John Edward Cribber,Concepts in Transition:The Searchfor a Nea,Definition of
Property, 1986 U.IEE.L.Rev. 1,5 ("[O]ne would expect property law to change as social
and economic conditions change.. . . [P]roperty concepts have not changed,but have only
adjusted`to the new condition of things."');Unger,supra note 3,at 548("In terms of rights
in light,air,and views,the change has always hinged on society's growing needs.").
136 U.S.v.Causby,328 U.S.256,264(1946).
137 Id.at 261.
138 Moskowitz,supra note 133,at 184 ("The evolution of the condominium-horizontal-
airspace ownership theory provides an appropriate illustration. The scarcity of land and the
desire for individual land ownership motivated the development of the theory.
Revolutionary construction methods made the theory a reality."),
i
20091 SOLAR RIGHTS 1251
would help to maximize the energy-saving technologies of the solar
collector.139
One might assume that ever-improving solar collector technology has
inspired the clarification and codification of solar rights. In fact, the vast
majority of courts appear to be hostile to the creation of solar rights,despite the
theoretical applicability of several strands of common law. Solar rights might
be created,for example,under nuisance rules,whether private or public. They
might also be created via court-assigned prescriptive easements, which have
been used in England and other places to protect solar access,which property
owners have enjoyed for some period of time, or under an implied easement
theory, which would apply to certain property subdivisions. None of these
theories has taken ]told on a wide scale. To the contrary, they have been
almost unanimously rejected.
This Part analyzes these legal possibilities, but it is important to note at the
outset that even if courts were receptive to solar rights theories, litigation will
remain perhaps the least efficient and most expensive method of resolving
solar rights. Court allocations can only assist with the protection of existing
solar collectors, meaning that they are not useful in helping an individual
decide whether to install a solar collector in the first place. More directly, the
costs of litigation, borne by each patty, exceed the costs of both express
agreements and governmental allocations, and can be disproportionate to any
anticipated benefit. Time also imposes a burden on solar rights seekers, as
litigation can take months, and sometimes years. Uncertain outcomes and the
existence of an adversary result in a stressful and complicated process, which
at least one party will find unfair. Tracing each of these deficiencies through
the judicial system demonstrates how courts' unwillingness to adapt to solar
technology has severely limited solar rights and suggests that solar rights
seekers should abandon the idea that courts will be willing allies in their cause.
A. Nuisance
Of the three possible court-made solar rights which this Part considers,
nuisance law seems the most capable of providing solar rights: well-developed
and flexible, its balancing test methodology lends itself to the weighing of
interests at stake in solar rights disputes.14' Despite this promise, however,
nuisance law has not effectively been engaged to create solar rights. An
analysis of the two key types of nuisance actions — private and public, the
difference being that private nuisance claims allege harms against one discrete
139 Yeary, supra note 78, at 141 (arguing that the "[p]otential use and enjoyment of
sunlight makes it legally as important as the airspace right").
140 See Gevurtz,supra note 13, at 113 ("Nuisance law, with its inherent flexibility, is a
useful supplement to zoning laws. . . . Zoning commissions must make all-or-nothing
decisions either to prohibit or allow a given use,but a court considering a nuisance action
can permit a use and at the same time require the user to compensate those injured by it").
1252 BOSTON UNIVERSITYLAWREVIEW [Vol. 89:1217
party or parties,while public nuisance claims allege harms affecting the public
as a whole—underscores this point.
Solar rights seekers have found only limited success in protecting access
through private nuisance claims. The Restatement(Second) of Torts defines a
private nuisance as "a nontrespassory invasion of another's interest in the
private use and enjoyment of land""' and requires that the invasion be
intentional and unreasonable.142 The Restatement's rules instruct courts to
weigh the harm and the utility of the activity; a private nuisance occurs if, on
balance, the harm caused by the activity exceeds its benefit. Obstruction of a
solar collector's access to light could therefore be considered a nuisance under
Restatement principles if, on balance,the harm caused by the obstruction(say,
rendering the solar collector defunct) is greater than benefits caused by the
activity(say,erecting a tall structure that would shade the collector)."' Before
1982, in the few cases that reached the courts, the judiciary declined to find
that obstruction of sunlight from reaching solar collectors was a private
nuisance.144 In 1982,however,the Wisconsin Supreme Count decided Prah r.
Maretti, which recognized a private nuisance claim for malicious obstruction
of a solar collector under Restatement balancing principles.145 In recognizing
the malicious motivation behind the obstruction, the Prah court attempted to
follow the longstanding judicial principle that so-called "spite fences" were
actionable as nuisances.14e The rationale for the spite fence rile is twofold: as
141 RESTATEMENT(SECOND)OF TORTS§821D(1979).
1- Id. §822(a).
141 See Lydon, supra note 31, at 386 (stating that solar access is protectable under
nuisance principles and offering"discomfort, annoyance, or disturbance of a landowner's
peace of mind"and junked automobiles,houses of prostitution, funeral homes,and stored
explosives"as possible nuisances).
144 See, e.g., Shu v. McCully-Citron Co., No. 56405 (Flaw. Dist. CF, Jan. 9, 1979)
(reported in Solar Access Right Denied by Hawaii Court, 1 SOLAR L.REP. 542,543 (1979-
1980)) (rejecting a plaintiff's request for an injunction on the construction of a high-rise
building which obstructed sunlight to the plaintiff s solar collector,because zoning on the
parcel on which the building was to be located allowed high-rises).
145 Prah v. Maretti, 321 N.W.2d 1825 185-88 (Wis. 1982) (considering the defendant's
choice to block the plaintiff's solar access a choice made out of spite and recognizing a
private nuisance in which the defendant`unreasonably impair[ed] the uses or enjoyment of
the other").
146 See, e.g., Ilomsby v. Smith, 13 S.E.2d 20, 25 (Ga. 1941) (reasoning that a fence
which "is done solely from malice, is an invasion of the right to light and air, and will
authorize a court to grant relief); Sundowneq Inc.v.King,509 P.2d 785,785,787(Idaho
1973) (holding that "no property owner has the right to erect and maintain an otherwise
useless structure for the sole purpose of injuring his neighbor" and identifying as a spite
fence an eighteen-foot-high sign which was placed sixteen inches away from a property
line);see also Gevartz,supra note 13,at 100 n.42, 101 nn.46&48. But see Fontainebleau
Hotel Corp.v.Forty-Five Twenty-Five Inc., 114 So.2d 357,359(Fla.Dist.CE App. 1959)
(arguing that spite should not give rise to any legal protections where one"causes injury to
another by cutting off the light and air.. .that would otherwise be available over adjoining
2009] SOLAR RIGHTS 1253
a public policy matter, actions motivated by malice or spite should be
discouraged, and as a legal matter, balancing the interests (in solar collector
cases) favors the solar rights seeker.147 The court insisted that its recognition
of this right did not unduly hinder land development,148 but merely recognized
a natural right inherent in property.149 Interestingly, the United States
Department of Justice filed an amicus brief arguing that finding for the
plaintiff would advance the national policy of encouraging greater use of solar
energy.150
Although solar collector proponents immediately lauded Prah as a sign that
courts were finally beginning to recognize solar rights, the decision has
attracted criticism. The dissent, cognizant that extreme hypersensitivity may
defeat nuisance claims,"' decried the majority's failure to characterize solar
collectors as hypersensitive uses."' The dissent also argued that solar
collectors themselves may be nuisances: "[S]olar panel glare may temporarily
blind automobile drivers,reflect into adjacent buildings causing excessive heat,
land in its natural state,regardless of the fact that the structure may have been erected partly
for spite"), At least one state,Maine,has passed a statute relating to spite fences. ME.REV.
STAT.ANN.tit. 17,§2801 (1964)(allowing a property owner to access an injunction remedy
against a neighbor who maliciously blocks the owner's access to sunlight). See also Martha
Freeman,Securing Solar Access in Maine,32 ME.L.Rev.439,451 (1980)(describing the
mechanics of this statute).
147 See Gevurtz,supra note 13,at 100-01 ("Two bases support this willingness to provide
limited protection for light and air. First, courts acknowledge that society morally
condemns actions motivated solely by malice and spite. Second. . .the judiciary applies a
nuisance law approach by balancing conflicting interests.").
148 Prah, 321 N.W.2d at 191 ("Recognition of a nuisance claim for unreasonable
obstruction of access to sunlight will not prevent land development or unduly hinder the use
of adjoining land. It will promote the reasonable use and enjoyment of land in a manner
suitable to the 1980's.").
149 J.B.Raid,The "Background Principles"of Natural Capital and Ecosystem Services—
Did Lucas Ot en Pandora's Boz?, 22 J.LAND USE&ENVTL.L. 525, 535 (2007) (calling
Prah one of a few"rare exceptions"to the general rejection of an American property law
canon which has been hostile to natural rights).
Iso Amicus Brief for the Justice Department at 15, Prah v. Maretti, 108 Wis. 2d 223
(1982).
151 See, e.g., Amphitheaters, Inc. v. Portland Meadows, 198 P.2d 847, 858 (1948)
(holding that a drive-in theater is a sensitive land use with respect to shadows,so its owner
was not entitled to relief from the floodlights at a neighboring racetrack). But see Lydon,
supra note 31, at 388 ("[S]everal cases support the proposition that sensitive use does not
bar nuisance protection, but rather is only a factor in the balancing equation." (citations
omitted)).
152 Prah, 321 N.W.2d at 197 (Callow, J., dissenting) (calling solar collectors "an
unusually sensitive use").
1254 BOSTON UNIVERSITYLAWREVIEW [Vol. 89:1217
and otherwise irritate neighbors."153 Most damagingly, the dissent
characterized Prah as an anomaly and a departure from other nuisance
decisions, a conclusion with which several cormncntators have agreed.1e4
Carol Rose, the eminent property scholar, has also criticized the majority for
muddying law by honing a crystal rule("that your neighbor has no right to the
sunlight that crosses your lot unless your neighbor has gotten an easement
from yon") into a mud rude (a possible nuisance action, the result of which
must be determined by a coml).155 Another commentator complained that
Prah should have limited its holding to cases involving sunlight as an energy
source.156 Whatever the criticisms, and despite the publicity,Prah has not had
a significant impact on solar access law. Wisconsin courts have cited it only
for its unrelated holding on sunnnaryjudgment,157 and only two or three courts
outside of Wisconsin have cited Prah favorably for its findings on nuisance.158
To consider a public nuisance claim, a court must rely on statutory
definitions of nuisances that affect the public generally. Public nuisance
statutes tell courts how to weigh different interests and specify the
requirements for a nuisance finding. For solar collector owners, the only
significant public nuisance statute is the California Solar Shade Control Act,
which names as a public nuisance any tree or shrub which, during the hours of
ten a.m. and two p.m., shades more than ten percent of the area around a
previously installed solar collector.159 Each day that the nuisance is not abated
151 Id at 195 n.3(noting that the first automobiles were considered nuisances to travelers
by horse, but when travel by automobile became dominant, "tile horse became the
nuisance"),
154 Dean N. Alterman,Reflected Sunlight Is a Nuisance, 18 ENvTL.L. 321, 337 (1988)
(viewing Pratt as a departure from court decisions that prohibited a private nuisance claim
with respect to conduct, which was legal, reasonable, and without malice); J. Michael
Banns, Return to Ancien! Lights? Prah v. Maretti, 1984 Der. C. L. Rsv. 101, 106
(describing the case as "a substantial departure from previously unyielding property law
concepts precluding a prescriptive right to light and air").
155 Carol M. Rose, Crystals and Mud in Property Lain, 40 STAN. L. Rrv. 577, 579
(1988).
156 Michael G.McQuillen,Prah v.Maretti:Solar Rights and Private Nuisance Law, 16 J.
MARSHALL L. Rev. 435, 443 (1983) (explaining that doing so "would have left the wcll-
settled law governing spite fences undisturbed"),
157 Potis,supra note 11,at 134.
"' See, e.g., Moly v. Midas Realty Corp.,431 N.W.2d 3805 383 (Iowa 1988) (calling
Prah and Tenn v. 899 Assoc. "persuasive"but finding them inapplicable to the case before
it,which dealt with views,and not light);Tenn v.889 Assoc.,Ltd.,500 A.2d 366,370(N.11.
1985)(considering the rationale of Prah and finding that"the law of private nuisance . . .
provides the appropriate standard for passing on a property owner's claims of interference
with interests in light and air"), But sce,e.g.,Sher v.Leiderman,226 Cal.Rptr.698,702-04
(Cal. Ct. App. 1986) (rejecting nuisance claim for light and air and urging legislative
involvement).
159 CAL.PUB.REs.CODE§§25980-25986(West 2007&Supp.2009).
20091 SOLAR RIGHTS 1255
is a separate offense,and the district attorney can prosecute offenders for up to
one thousand dollars per offense.16' The law does not apply to vegetation that
began growing prior to the installation of a solar collector,vegetation grown on
timberland, or agricultural crops.161 Any city or county can, with a majority
vote of the governing body, exempt itself from the Solar Shade Control Act.162
Critics of the Act complain that it should also apply to structures that block
access, that it should not grandfather existing vegetation, that it should not
allow municipalities to opt out, that it may raise takings claims, and that it
gives too much power to solar collector owners because they are required to do
nothing more than report a violation to a public prosecutor."' The Act has
also been criticized for operating as a public nuisance statute, despite the fact
that its definition of nuisance appears to include only nuisances of a private
nature.164 The Act's broad penalties and enforcement mechanisms, such as
prosecution by a local district attorney, would not be available to individuals
seeking to bring a private nuisance claim. As a result,it might be said that the
Act may do too much to broaden the remedies available to those with private
nuisance claims, under the guise of a public nuisance statute. The Act brings
the whole body of public nuisance law into solar collector disputes, where
1b0 Id §25983.
161 Id§§25982,25984.
162 Id § 25985. See also, e.g., SANTA CRUZ,CAU.., COUNTY Cone § 12.28.040 (2007),
available at http://ordlink.com/codes/santacmzco/_DATA/TITLEI2/Chapter_12_28_
SOLAR_ACCESS_PROTECT/12_28_040_Protection_of solar blind (covering new
construction); DEL MAR, CAL, MuN. CODE § 23.20.100 (1997), available at
http://mt .delmar.ca.us/Govemment/Municipal"/o20Code/Chapter_2320.pdf("In the event
adjacent landscaping deprives a site of reasonable solar access, and/or shades an existing
solar collection device, the owner of a site so affected may petition the City Council for
abatement of the foliage as a public nuisance."). -
163 See Bradbrook,supra note 18,at 184("The most obvious weakness is that the statute
applies solely to shading from trees and shrubs and does not encompass shading caused by
buildings or other structures.");Eisenstadt,supra note 2,at 34-35 (identifying the existing
vegetation and opt-out issues as significant weaknesses of the statute);Gergacz,supra note
30, at 21 ("[T]he Act may involve a `taking' of a neighbor's airspace without just
compensation."); Paris,supra note 11, at 138 (identifying as a criticism of the Act that it
"may lead to frivolous complaints and harassment of neighboring landowners since solar.
energy users must merely submit a complaint to the prosecutor");Swenson et al.,supra note
30,at 7-8("The Solar Shade Control Act fails to offer comprehensive protection to the right
to make use of potential solar insulation in that:(1)the Act does not cover shade caused by
structures (though set back requirements and height limitations in zoning ordinances may
offer effective protection),(2)existing vegetation trumps new solar collectors(an important
consideration in light of the recent solar power renaissance), and(3) the Act allows cities
and counties to opt out of the Act by enacting an ordinance exempting themselves from its
jurisdiction.").
1et See Gergacz,supra note 30, at 24 ("Clearly, conduct prohibited by the Solar Shade
Control Act does not inconvenience or annoy the general public. The annoyance is between
adjoining landowners.").
1256 BOSTON UNIVERSITYL4WREVIEW [Vol. 89:1217
other language might have suffrced.161 Perhaps because of the limited
circumstances in which it applies, few cases involving the Act have come to
court.166 However,the law gained national attention when it was invoked in a
dispute that pitted one environmental good(the growth of endangered redwood
trees)against another(solar collector use).167
Given the paucity of relevant judicial activity, it seems unlikely that
nuisance actions —whether private or public—will provide the solution to the
challenge of allocating solar access rights.168 The unpredictability of outcomes
may be the most significant deterrent:no matter how many cases courts decide,
nuisance law always involves a highly individualized analysis of the applicable
facts.16e Solar collector owners may be unwilling to bear the high costs of
litigation for uncertain results.17' Nuisance litigation imposes not only private
costs, but also the public cost on the courts, costs related to prosecution of
public nuisances, and the consequences of erroneous judgments,"' The
remedy granted may not necessarily mitigate these costs. On the one hand, a
solar collector owner bringing a nuisance claim may want to receive damages
and attorneys' fees to recoup out-of-pocket expenses and other losses. On the
other, she may want an injunction to stop the nuisance itself—the only path to
165 See Bradbrook,supra note 27, at 262("One may validly ask why it is necessary to
declare the shading of solar collector panels to be a nuisance and so import all the
complexities of that body of law into the resolution of any dispute when it would be possible
to create legislation providing a simple remedy without resorting to the law of nuisance at
all.").
166 See, e.g.,Zipperer v. County of Santa Clara, 35 Cal. Rptr. 3d 487,492-95 (Cal. Ct.
App.2005)(finding that a homeowner's claims that local government had not used the Act
to protect his solar collector from shade caused by vegetation legally insufficient because
the local government had passed an ordinance exempting itself from the Act).
161 See Barringer,supra note 39 (concluding that in the end, one property owner was
forced to prone redwoods that shaded a neighbor's solar panels).
166 See Kyle Graham, Why Torts Die,35 FLA.ST.U.L.Rev. 359,389(2008)(observing
that solar nuisance actions have joined dead torts such as heartbalm torts, the tort of
mishandling of dead bodies,and the tort for insults).
169 See Vernon N.Kerr,New Mexico's Solar Rights Act: The Meaning of the Statute, I
SOLAR L. REP. 737, 741 (1980); Sampson & Claim, supra note 38, at 418 ("[T]he
development of nuisance law as a means by which to protect access to sunlight is likely to
be a slow,piecemeal effort ofplaintiffs establishing...the facts of individual cases.").
110 Eisenstadt,supra note 2,at 30(recognizing the costs and unpredictability of nuisance
law as a means of guaranteeing solar rights);Pfeiffer,supra note 15,at 290(hypothesizing
that"it might take years to reach a final resolution . . . and the ensuing expense and delay
certainly would not be conducive to widespread installation of solar energy systems").
191 Williams,supra note 31,at 444(defining the costs of erroneous judgments to include
the cost of creating rights when it would have been efficient to deny them(and vice versa)
and the cost of defining solar access either too generously or too narrowly).
2009] SOLAR RIGHTS 1257
a secure right in solar access. Conflicting goals with respect to the remedy
may further deter potential litigants.172
B. Prescriptive Easements
Like nuisance law, the law of prescriptive easements provides a possible,
but imperfect, means of securing solar rights through the courts. A
prescriptive easement refers to a right of access "created from an open,
adverse,and continuous use over a statutory period,"which may be established
without the consent of the property owner against whom the easement is
claimed.173 Solar prescriptive easements date back to at least the reign of the
Roman emperor Justinian, under whom codified laws prevented neighbors
from blocking sunlight, which had previously been enjoyed by a property
owner for light, heat, or sundial operation.174 A judge would decide the
reasonableness of the expectation of sunlight one party could enjoy and the
reasonableness of the amount of sunlight a neighbor might block.175 Similarly,
in England, the common law included an "ancient lights" rule that granted a
property owner the right to prevent a neighbor from blocking light that reached
the interior of her building and that she had enjoyed continuously for twenty
112 See MILLER ET AL.,supra note 43,at 7 ("Another limitation of nuisance suits is that
only damages, and not injunctive relief, may be available in about half the jurisdictions
(those using a `balance of conveniences' approach)."); Ralph E.Becker,Jr.,Conmton Lam
Son Rights: An Obstacle to Solar Heating and Cooling?,3 J. CONTEMP. L. 19, 30 (1976)
(predicting damages as a remedy in about half of the jurisdictions, despite the fact that
"[i]njunctive relief would seem almost imperative in a solar energy nuisance action");
Bradbrook,supra note 18,at 183(predicting that a"remedy applied(if any)is likely to be
money damages rather than an injunction");Polis,supra note 40,at 365-67(analyzing the
Calabresi & Melamed approach to nuisance actions as it may be applied to solar access
cases,finding that social utility can play some role in determining whether injunctive relief
or damages are appropriate); Williams, supra note 31, at 445 (considering a conditional
nuisance right in which `the plaintiff [solar collector owner] would not be entitled to
injunctive relief,only to damages"),
1.. BLACK'S LAw DICTIONARY,supra note 25,at 587.
17'1 3 THE CIVIL LAN INCLUDING TILE TWELVE TABLES,THE INSTITUTES OF GAIUS, THE
RULES OF ULPIAN, THE OPINIONS OF PAULUS, THE ENACTMENTS OF JUSTINIAN, AND THE
CONSTITUTIONS OF LEO 283(S. P. Scott,trans., 1932)(circa 450 B.C.E)(Paulus,Institutes,
Book 11)(stating that where a servitude applied,"a neighbor shall not raise his building any
higher against our will, so as to lessen the amount of light in out, house"); id. at 285-86
(Ulpianus,On Sabinus,Book XXIX) (stating that if a tree is planted"so as to cut off the
sunshine from a room,or from a sundial,it must be said that,by producing shade in a place
where sunshine was necessary,he acts in violation of the servitude imposed").
175 See Jordan &Perlin,supra note 3, at 593 ("To build without leaving a neighboring
house a minimum of light, a builder had to have a servitude (altfus tollendi) over the
neighboring land. . . . On the other hand, to have the right to more light than the bare
minimum, a neighbor had to have a servitude (altias non tollendi) against the builder to
prevent him from building higher. The decision as to what constituted a reasonable amount
of light was left to the judge or arbiter.").
i
1258 BOSTON UNIVERSITYLA W REVIEW [Vol. 89:1217
years.176 The amount of light protected was measured by the amount of
indirect sunlight required to illuminate half of a room beyond the "grumble
line"—the point beyond which a normal person might complain about lack of
light.177 As one English commentator put it:
[The ride was justified] on the one hand, [because] if persons were so
indifferent as to allow their neighbours to use lights for twenty years
without objection, the continuance of the windows could hardly be
prejudicial; and, on the other hand, [because] it was inconsistent with
justice to compel people to forego an employment which they had used
without hindrance.178
The modern version of this rule has now been codified.171
t76 See BLACK'S LAW DICTIONARY, supra note 25, at 101 (defining "ancient-lights
doctrine"as"[t]he cornmon-law principle by which a landowner acquired,after 20 years of
uninterrupted rise, an easement preventing a neighbor from building an obstruction that
blocks light from passing through the landowner's window");KrNFLM EDWARD DIGHY,AN
IN'T'RODUCTION TO THE HISTORY OF THE LAW OF REAL PROPERTY 182(1897)(defining ancient
lights as a prescriptive negative easement of light and air over property of adjoining
neighbor). Nate that sixteenth-century English common law did not recognize an action for
obstruction of access to light and air. See,e.g.,Bury v.Pope,(1586)78 Eng.Rep.375,375
(bolding that Bury did not have a right to a nuisance for Pope's"stopping of[Bury's]light"
by Pope's building a house close to Bury's property line). Note also that ancient lights
violations could be enforced in England through a nuisance action. Blackstone called a
nuisance the act of"erect[ing]a house or other building so near to mine that it obstructs my
ancient lights and windows." 3 WILLIAM BLACKSTONE,COMMENTARIES ON THE LAWS OF
ENGLAND 216-17;See also 2 FRANCIS MILLIARD,THE LAW OF TORTS ON PRIVATE WRONGS 2-
3(1866)(indicating that a landowner invoking ancient lights could enforce the right to light
through a nuisance action).
177 See,e.g.,Charles Semon&Co.v.Bradford Corp.,2 Ch.737,747-48(1922)(defining
the "grumble line" as "the point whereat ordinary common sense people would begin to
grumble at the quantum of light[, or as] the point in the room at which the percentage of
illumination fell to 0.4 of the sill light"); Osofsky, supra note 32, at 638 (explaining that
"[t]he light guaranteed by the doctrine is not direct sunlight—only enough indirect sunlight
to go about your life indoors without grumbling");Pfeiffer,supra note 15,at 289(observing
that"[a]t least half a room had to remain beyond the`grumble line'—the point at which a
normal person would start to complain about the lack of light—in order to preclude legal
action to enforce the easement").
178 HUMI'HRY W. WOOLRYCH, A PRACTICAL TREATISE OF THE LAW OF ANCIENT AND
MODERN WINDOW LIGHTS 3(1864).
179 See Prescription Act, 1832,2&3 Will.4,c.71, § 3(Eng.)("When the[a]ccess and
[u]se of[flight to and for any[d]welling[blouse,[w]orkshop,or other[bluilding shall have
been actually enjoyed therewith for the Poll [p]eriod of [tlwenty [y]ears without
[i]nterruption, the [r]ight thereto shall be deemed absolute and indefeasible, any local
[u]sage or[c]ustom to the contrary notwithstanding,unless it shall appear that the same was
enjoyed by some [c]onsent or[a]greement expressly made or given for that [p]urpose by
[d]eed or[w]riting.");Act for a Limitation of Actions and for Avoiding Suits in Law,1623,
21 Jac.,c. 16(Eng.)(establishing the"twenty years"rate for the first time).
20091 SOLAR RIGHTS 1259
According to repotted cases and historical accounts,American courts at first
embraced the ancient lights doctrine and its allowance of prescriptive
easements in light.180 Treatises18' and courtsl82 confirmed, however, that by
the late nineteenth century, the ancient lights rule had been rejected
everywhere in this county, except in Louisiana.183 Courts justified this
rejection on the grounds that settlement patterns differed in seventeenth-
century England and nineteenth-century America, and that applying the rule in
rso See, e.g., Clawson v. Primrose, 4 Del. Ch. 643, 672 (1873) (stating that courts'
adoption of ancient lights was necessary and "can be altered only by the Legislature");
Gerber v. Cnabel, 16 I11.217,219(1854)(finding"no reason for the inapplicability of rales
in relation to air and light in houses,and that air should be as wholesome and agreeable here
as [in England]"); Story v. Odin, 12 Mass. (7 Tyng) 157, 160 (1815) (describing the
applicability of a rule to two adjacent houses in Boston); Robeson v. Pittenger, 2 N.J. Eq.
57, 64 (N.J. Ch. 1838) (stating that `the same [ancient lights] rules which have been
established in the English courts . . .apply with the same force to us");Berkeley v. Smith,
68 Va.(27 Gratt.)892,898(1876)("Where ancient lights have existed for upward of twenty
years undisturbed, the owner of an adjoining lot has no right to obstruct them"); 2
BILLIARD,supra note 176,at 2,8(recognizing that"the modern rule is,that,although it is
not alleged that the house is an ancient one,or that the plaintiff is entitled by prescription to
the easement,he may prove an ancient right,if necessary to his case"and that an action may
be maintained only if property values diminish);II. G.WOOD,A PRACTICAL TREATISE ON
THE LAW OF NUISANCES IN THEIR VARIOUS FORMS § 152 (1875) ("There are a few early
cases in which this right was recognized,"),
181 See WILLIAM WAIT,ATREATTSF.UPON SOME OF THE GENERAL PRINCIPLES OF THE LAW,
WHETHER OF A LEGAL OR OF AN EQUITABLENATURE 295(1877)("[T]he English doctrine of
ancient lights has not been adopted in this country."); WOOD, supra note 180, § 153
(asserting that "in this country, no prescriptive right to have the light and air enter the
windows of a building laterally over the land of another can be acquired,and in the absence
of an express or implied grant to that end,an adjoining owner may build upon his own land
so as to completely shut out the light of his neighbor's windows opening upon his land,and
no action can be maintained therefor'); see also 46 A.C. FREEMAN, THE AMERICAN
DECIsiONs CONTAINING THE CASES OF GENERAL VALUE AND AUTHORITY DECIDED IN THE
COURTS OF THE SEVERAL S'T'A'T'ES 581-82(1886)(asserting eleven years after the Wood and
Wait treatises that the ancient lights rule"forms no part of the law of this country").
VQ See, e.g., Turner v. Thompson, 58 Ga. 268, 271 (1877); Parker v. Foote, 19 Wend.
309,318(N.Y. Sup. Ct. 1838)("There is . . . no principle upon which the modern English
doctrine on the subject of lights can be supported. It is an anomaly in the law.");Powell v.
Sims, 5 W.Va. I, 5 (187 1)(finding that because English common law does not apply,the
court is"free to adopt and apply...such principles consistent with the rights of the parties.
. .as will in our judgment best comport with the public good and the existing condition of
things in this country"). Later commentators have noted that the West Virginia court failed
to cite to statutory language that specifically mentioned English common law as a reference
for the state's developing legal system. See James Audley McLaughlin, The Idea of the
Common Lair in Mest Virginia Jurisprudential History!' Morningstar v. Black & Decker
Revisited,103 W.VA.L.REV. 125, 132(2000).
183 See Palomeque v. Pmdhomme, 664 So. 2d 88, 91 (La. 1995) (indicating that
Louisiana common law allows prescriptive easements in light to be established).
i
1260 BOSTON UNIVERSITYLAWREVIEW [Vol. 89:1217
rapidly-growing cities and towns would impede development.184 By
prioritizing land development over access to light, American courts boosted
not only urban growth,but also individuals' rights to develop their properties
without undue hindrance, as such individuals might have otherwise found it
difficult to discover(and thereafter extinguish)their neighbors' continuing use
of Iight.185 When deciding ancient lights rule cases, courts have often invited
legislatures to set forth clear rules regarding prescriptive easements in lightJ86
Several legislatures have responded by prohibiting such prescriptive easements
altogether."'
Despite such an infertile judicial and legislative enviromnent, the idea
lingers that prescriptive casements may be an effective method of establishing
lasting solar rights. Proponents of this view might believe that courts will
184 See,e.g.,Lynch v.Hill,6 A.2d 614,618(Del.Ch. 1939)(overruling Clawson,4 Del.
Ch. 643,by stating that the ancient lights rule was"wholly unsuited to our conditions. . .
and would necessarily cause mischievous consequences in our growing cities, towns, and
villages");Parker, 19 Wend.at 317-18(rejecting the rule in dicta,stating that"mischievous
consequences"would occur if the rule were applied to the rapidly growing developments in
the United States);see also Fontainebleau Hotel Corp.v.Forty-Five Twenty-Five Inc., 114
So. 2d 357, 358-59 (Fla. Dist, Ct. App. 1959) (stating that a property owner's rights may
only be curtailed by a"right of enjoyment of...property which is recognized and protected
by law,"and excluding from this protection prescriptive easements in light and air).
185 See Gergacz,supra note 54,at 146(arguing that"[u]nlike a roadway or a drain across
property,use of light and air by a dominant tenant is not discoverable through observation
by a servient tenant"); Gevurtz, supra note 13, at 109-10 ("Two policy arguments are
normally made in favor of land development[as a priority against sunlight access]. The first
equates land development with progress and economic growth and thus favors it for its own
sake. The second emphasizes the landowners' interest in developing property as they
wish.").
"6 See, e.g.,Fontainebleau, 114 So. 2d at 360 (asserting that"to change the universal
tide[by providing a right to light and air] ...amounts...to judicial legislation").
187 See, e.g.,COLO.Rev. STAT. § 38-32.5-101 (2008) ("[A] solar easement shall not be
acquired by prescription.");BONN.GEN.STAT.ANN. §47-25(West 2004)("No occupant of
real estate may acquire, by adverse occupation, the right to keep, sustain or enjoy any
window or light, so as to prevent the owner of adjoining premises from erecting and
maintaining any building thereon."); GA. CODE. ANN. § 44-9-2 (2002) ("A right to an
easement of light and air passing over another's land through existing lights or windows
may not be acquired by prescription......);Kr.Rev.STAT.ANN.§381.220(2)(LexisNexis
2002)("[A]solar easement shall not be acquired by prescription.");MASS.GEN.LAWS ANN.
ch. 187, § 1 (West 2003) ("Whoever erects a house or other building with windows
overlooking the land of another shall not,by the mere continuance of such windows,acquire
an easement of light or air so as to prevent the erection of a building on such land."); R.I.
GEN.LAWS§34-7-3(1995)("Whoever has erected or may erect any house or other building
near the land of another person, with windows overlooking the land, shall not, by mere
continuance of the windows, acquire any easement . . . "); WASH. REv. CODE ANN. §
64.04.160(West 2005) (prohibiting"the creation of an implied easement or a prescriptive
easement"); W.VA.CODE ANN.§2-1-2(LexisNexis 2006)(enshrining,in 1868,the state's
rejection of the ancient lights rule).
20091 SOLAR RIGHTS 1261
begin to recognize and respond to the increasing importance of sunlight as a
valuable economic commodity.1 ' In recognition of the value of these
collectors, courts could be willing to establish a limited application of the
ancient lights rule, modeled after the English doctrine, to protect solar
collectors. A prescriptive easement created by courts could, for example,
provide a permanent right in the solar skyspace over adjoining lands, if
previously enjoyed for a certain number of years by the solar collector owner.
Stich an easement could prevent the servient tenant from obstructing sunlight
flowing through that solar skyspaee.189 As is the case in England, property
owners could register prospective prescriptive easements with local
authorities.19' Such property owners could be required to identify the servient
and dominant estates and the solar envelope beyond which the solar skyspace
required by the solar collector would be obstructed.191 Notice could be given
to affected parties.192
Although the possibility of granting prescriptive easements for solar
collectors seems appealing, courts are unlikely to snake such leaps. England's
ancient lights rule, which requires a twenty-year occupancy period and which
protects only a minimum amount of indirect light that reaches enclosed interior
spaces, would hardly address the practical requirements of a solar collector
186 See Prah v. Maretti, 321 N.W.2d 182, 190 (Wis. 1982) (criticizing other courts'
rationale for rejecting ancient lights by saying that "[t]he need for easy and rapid
development is not as great today as it once was, while our perception of the value of
sunlight as a source of energy has increased significantly");Bennett,supra note 89,at 231
(observing that to the extent Prah recognized"the increasing importance of sunlight as an
energy source.. .the court may have[also recognized that] society now values sunlight so
there is a right to light,at least insofar as the balance of the equities lies in favor of the solar
energy consumer");Bersohn,supra note 6,at 126(arguing that"[a]mple building lot sizes
and abundant fossil inels, conditions which supported the role against prescriptive
acquisition of light and air rights,are rapidly fading into history");Cribbet,supra note 135,
at 22(commending the Proh court for responding"to a new social climate"),
119 Gergacz,supra note 30,at 5("A solar access easement is a negative easement which
prohibits the servient tenant from obstructing the sunlight flowing through a defined section
of airspace above his property.").
190 Right of Light Act, 1959 7 &8 Eliz.2,c. 56,§ 2(1)(Eng.)(allowing landowners to
register with local authorities "[f]or the purpose of preventing the access and use of
Registration light from being taken to be enjoyed without interruption"). Note that English
rales do not apply specifically to solar collectors. See id
191 See id. § 2(2)(a)-(b) (applying similar rales to prospective prescriptive easement
recipients,but with respect to structures,as the English ancient lights rule protects only light
accessible within a structure).
192 See id. § 2(3)(a) (requiring that adequate notice be given to those "who, in the
circumstances existing at the time when the certificate is issued, appear to the Lands
Tribunal to be persons likely to be affected by the registration of a notice in pursuance of an
application"). The Act also allows for temporary notice to be given in cases of"exceptional
urgency." Id. §2(3)(b).
1262 BOSTON UNIVERSITYLAWREVIEW [Vol. 89:1217
owner.193 A potential solar collector user could not depend on a right vesting
twenty years into the future,and might therefore decline to invest in expensive
solar technology.194 Moreover, potential users might not want to gamble on
courts' application of precedent meant to protect indirect lighting of building
interiors to direct lighting required by solar collectors.195
Irrespective of judges' attitudes towards prescriptive easements for the
protection of solar rights, practical reasons militate against reliance on court-
created prescriptive easements. Prescriptive easements may inisallocate
incentives, causing landowners to rush to develop their properties and file
notices to extinguish possible claims by neighbors wishing to build solar
collectors.196 If a good recording system is not in place, title searches may
become extremely difficult and may reduce certainty in land purchases.191
And as described above, the inefficiencies of court actions will deter many
solar rights seekers, and the outcomes will not satisfy all patties, leading to
claims of unfairness.
193 See Stang],saga note 55,at 583("[T]he essential shortcoming to using the doctrine
of ancient lights as a solution to the solar access problem is the familiar one that conies from
trying to adapt an existing legal theory to a problem it was not intended to solve."); The
Allocation of Sunlight,supra note 124, at 430("The prescriptive period is far too long to
offer any protection to the purchaser presently considering whether to convert his home to
solar heating. That the doctrine of ancient lights generally relates only to reading light,not
to uninterrupted sunlight,makes it unsuitable,without drastic judicial expansion,to sunlight
collectors,most of which require entirely unshaded conditions.").
194 See Gergacz,supra note 54,at 152("The homeowner or businessman who installs a
solar energy system wants immediate protection,because his fuel supply is otherwise at the
mercy of his neighbor,");Marasco,supra note 56,at 841 ("[T]he prescriptive period is too
long to offer any protection to a purchaser considering solar energy in a residential or urban
area.").
195 See KRAEMER,supra note 14,at 132(observing that"a solar collector requires a great
deal more light than that required to make a man refrain from a`grumble"');MILLER ET AL.,
supra note 43,at 5 (arguing that even if the ancient lights doctrine is exhumed, "it would
require such great modification that even a willing judiciary may refuse to make the leap
without a legislative assist'); Lyden,supra note 31, at 373 (arguing that that"the ancient
lights doctrine is a legal anachronism having no bearing on the viability of a nuisance action
for sunlight obstruction");Potis,supe note 11,at 130(calling it"unlikely that this doctrine
will ever assist a contemporary solar energy user").
196 Berryhlll&Parcell,supe note 6,at 432-33(characterizing this race as"[a]neighbor
contiguous to the tract of a solar energy system user would be forced to develop his land
perhaps well in advance of the time necessary or desired in order to avoid the acquisition of
an easement by the solar user");Williams,supra note 31,at 452.
"o See Bersohn, supra note 6, at 119 ("[T]he cost of title searches may have been
increased considerably, for a cautious solicitor representing a client purchasing a site for
development now must search not only for clouds on the title of the lot itself,but also for
light obstruction notices registered against potential dominant tenements.").
20091 SOLAR RIGHTS 1263
C. Implied Easements
Less ink has been spilled over implied easements than prescriptive
easements, perhaps because easements by implication occur only in very
limited circumstances. A court may create an implied easement only if"an
owner of two parcels of land uses one parcel to benefit the other to such a
degree that, upon the sale of the benefited parcel, the purchaser could
reasonably expect the use to be included in the sale."198 The court must
therefore find unity of ownership prior to the conveyance of the new parcel,
intent among the parties to create an easement,and a need for the easement.199
The rationale for implied easements rests in the notion that given the facts,the
parties did intend, or would have intended, to include the easement in the
conveyance.200 Perhaps the most common example of an implied casement is
a roadway on land conveyed to another, over which roadway the conveyor still
requires access.
In the solar context, a solar collector owner who has sold a portion of her
property might later seek an implied easement to prevent the buyer from doing
something on the buyer's property (building a tall structure, for example)
which would prevent sunlight from reaching the solar collector she used to
meet her energy needs for years preceding the sale.20' After establishing unity
of ownership, she would then have to argue that the patties intended to create
an easement in light, but merely failed to do so in express terms. She would
have to prove the intent of a party who—by virtue of being in court—firmly
opposes her claim and would not admit to having such an intent. Finally, she
would have to convince a court that she depends so heavily on the energy
produced by a solar collector that it is rendered a "necessity" under common
law precedent. With so much to prove, a solar rights seeker has a burden,
which, in most cases, is extremely difficult to overcome. Indeed,no reported
cases, either at the state or federal level, have created implied easements for
solar collector access. Most courts reject the possibility outright 202 The
greatest barrier to implying an easement in solar collector cases appears to be
the showing of necessity. A West Virginia court, for example, required a
"clear showing of necessity," stating that implied easements for light should
198 BLACK'S LAW DICTIONARY,supra note 25,at 587.
199 Matuson, supra note 56, at 842 (listing these three requirements and adding,
"believing that implied easements unduly burden land and its alienation and proper
improvement,courts continue to be reluctant to find that these elements are present").
2" Berryhill&Parcell,supra note 6,at 435.
201 For another example, see Matuson, supra note 56, at 843, describing a scenario
"where property has a building located upon it equipped with a solar collector and an
adjacent parking lot[,and where ilf the lot is later sold or transferred,the new owner may be
unable to block access to the collector."
202 See JON W.BRUCE&JAMES W.ELY,JR.,THE LAW OF EASEMENTS AND LICENSES IN
LAND§4:29 n.2(2008)(citing cases from California,New York,Nevada, and Washington
which call the rejection ofimplied easements in light"well-settled").
1264 BOSTON UNIVERSITYLAWREVIEW [Vol. 89:1217
not "impede progress by prohibiting improvements to property necessary to
keep in line with the development of the cotmnunity."203 Other barriers, such
as proving intent,also endure.
Coutts should no doubt do more to weigh competing values, including
public policy, when considering such cases 20't But even in the unlikely
circumstance that courts begin to embrace the implied solar access easement,
the limited circumstances in which such easements may occur would severely
limit its utility. Implied easements in light have only been granted in three
circumstances. First,they have been granted where the"light was so necessary
to the trade use of a business premises that without it the property would be
vahteless."205 Under this standard, courts may be reluctant to find that access
to solar collectors is necessary, so long as alternative forms of energy remain
viable.20' Second,the easement seeker may have a claim if her access to light
somehow related to a right of passage(the more common basis for an implied
easement).207 It is difficult to see how this exception could be applied with
respect to solar collectors. Third, other successful cases involve implied
easements claimed by owners of private property that abuts public streets?08
Unless a solar collector owner asserts an implied easement over a public street,
this exception is as Unhelpful as the others. Only a few courts (and one state
legislature) have allowed property owners to overcome the presumption
against implied easements for light.209 This state of affairs seems unlikely to
change in the immediate future.
203 Nomar v.Ballard,60 S.E.2d 710,719(W.Va. 1950).
264 See Unger,saprn note 3,at 549("[R]ather than presuming the American common law
regarding light,air,or view rights to be a general rejection,courts would be better served by
a standard evaluating the competing considerations to determine whether public policy
weighs in favor of such a right,and rule accordingly.").
los polis,saprn note 40,at 362.
2°6 See Becker,supra note 172,at 26.
209 Polis,saprn note 40,at 362(mentioning rights of ingress and egress).
208 See BRUCE&ELY,supra note 202,§4:29,n.10(noting United States Supreme Court,
Iowa, Mississippi, and Utah cases, which allowed implied easements over public streets);
Moskowitz,supra note 133,at 197-98 ("An easement to light beaming across a street will
be implied in favor of a parcel of property abutting on such a street,regardless of the history
of the devolution of title held by the abutting landowner and the manner in which the street
was established."). The Supreme Court wrote,"1t is impossible for us to conceive of a city
without streets,or any benefit in streets,if the property abutting on them has not attached to
it as an essential and inviolable part, easements of light and air as well as of access."
Mutilker v.New York&Harlem R.R.Co.,197 U.S.544,563(1905).
209 See GA.Cour,ANN. §44-9-2(2002)(providing that"when a person sells a house and
the light necessary for the reasonable enjoyment thereof is derived from and across
adjoining land belonging to such person,the easement of light and air over such vacant lot
shall pass as an incident to the house sold as being necessary to the enjoyment thereof');
BRUCE&ELY,supra note 202,§4:29,n.3(citing Minnesota,New Jersey,Pennsylvania,and
Washington, D.C. cases that appear to allow implied easements in light and/or views);
2009] SOLAR RIGIITS 1265
After a review of the judicial developments with respect to nuisance,
prescriptive easements, and implied easements, it is difficult to imagine that
courts could ever become fully engaged with the development of a solar lights
regime. Even if courts suddenly became receptive to solar rights, litigation
would be a poor strategy for solar rights seekers for many reasons, including
the uncertainty of the outcome and the related transaction costs. Rather than
repeating "ancient' debates about ancient lights and other topics, modern
scholars should shift their focus away from the courts. Instead, as the
conclusion of this Article suggests, they should join a new debate about how
jurisdictions might adopt an integrated approach,which addresses the concerns
of both solar rights seekers and possible burdened patties.
CONCLUSION
Some of the "greatest minds in American law," including Oliver Wendell
Hohnes,Joseph Story,and Benjamin Cardozo,have considered the question of
solar access 210 Despite their efforts, and the concentrated efforts of legal
scholars in the late 1970s and early 1980s, little progress has been made in
ensuring solar rights. This Article urges a revival of their debate, in light of
some lessons learned since.
Advocates may have three broad avenues toward solar rights: express
agreements, governmental allocations, and court assignments. When viewed
through the deal lenses of efficiency and transaction costs,court assignments—
over which perhaps the most scholarly ink has been spilled—appear to be the
least desirable method for obtaining solar rights. Accordingly, the courts
should play only the smallest of roles in the reinvigorated debate. Instead
(absent the creation of a new property right outside of the nuvaerus clauses),
advocates should focus on developing integrated schemes that combine express
agreements and governmental allocations. Each scheme should meet
jurisdiction-specific needs and should be adapted to consider many factors.
The articulation of this integrated scheme is considered in a companion piece
to this Article.211
Gergacz,sapra note 30, at 7 (finding that because some"state courts have upheld implied
casements...the creation of an implied solar-access easement is still possible").
210 Gergacz, supra note 30, at 123 (indicating that "Oliver Wendell Holmes struggled
with[the access issue]both as an attorney and as a judge,as did Story and Cardozo').
211 Bronin,supra note 10.
Page 1 of 1
Kyle Kritz-Re: Proposed Freestanding Solar Array Amendment Information
From: Jack Potter<jackpotter@adobereo.com>
To: Kyle Kritz<Kkritz@cityofdubuque.org>
Date: 05/28/2015 4:32 PM
Subject: Re: Proposed Freestanding Solar Array Amendment Information
Kyle , a limit of 100 square feet„ & 10' height are NOT a "reasonably sized structure" when speaking
about electric
for an average homeowner . That might produce 4%to 14% of their annual electric needs.
LET'S GET REAL
100 square feet is NOT a "reasonably sized structure"
a 1,000 sq. foot. might be called "reasonable" but not on a 1 acre or larger lot..
Why do you have this desire to "PUNISH PEOPLE' on their own private property.
10 foot is too short...20 foot could be called reasonable.
What is "compatible with surrounding property" when your solar will be the first in 50 square blocks?
Do I have the"right to drill a well in my own back yard" ?
My brother in law has had "backyard solar" for 42 years in San Diego...That is his "right"!,
If built to all code standards; it is a right,just like that well, to make your own electric".
Simple set backs, and a building permit and a solar electrical inspection, is all that is needed.
Respectfully,Jack Potter, solar consultant
with ADOBE REO, .,Cascade,Grinnell, Dodgeville and Galena.
Clielc here to report this email as spam.
MAY 2 8 201515
CITY OF DUBUQUE
PLANNING SERVICES DEPARTMENT
file:///C:/Users/Idcritz/AppData/Local/Temp/XPgrpwise/55674317DBQ_DODBQ_PO 100... 05/28/2015
Solar Energy Can Be a Health Hazard
Keywords: solar power, wind power, inverters, dirty electricity
Generating electricity from the sun and the wind is gaining popularity. In many
parts of the world,governments encourage their citizens,businesses and schools to
put solar panels on their roofs,and wind farms are sprouting up in many places.
Some of these technologies are unfortunately a health hazard to people who have
electromagnetic hypersensitivity (EHS). These are people who get sick from
electromagnetic radiation in very small amounts,such as that which comes from
cell phones,computers and other electronic appliances.
There are studies that suggest that radiation of the type coming from solar electric
systems (some of which have been dubbed"dirty electricity")may have long-term
health effects on healthy people as well, and may cause hyperactivity (ADHD)in
school children. In the following,we will look at the problems with solar and
wind generators, and how one can use them without compromising health.
Solar systems
Putting solar panels on the roof of one's home,business or school is a good way to
provide an alternative to polluting conventional power plants. However,people
with electromagnetic hypersensitivity may not even be able to enter or be around
such a building. Since some of the milder symptoms of this syndrome are
common and non-specific,such as headaches and restlessness, a person using the
building may not even know his or her symptoms are caused by the solar system.
Modern solar systems use components that radiate radio frequency
electromagnetic radiation,which can cause the symptoms. The main problem is
the inverter,which is a device that takes the electricity from the solar panels and
turns it into alternating current (AC) and puts it out on the electrical grid. The
inverter generates radio frequency radiation. The wires connected to the inverter
act as antennas,so the radiation may be icp ked up hundreds of feet away from the
inverter. There have been cases where a solar-electric system became a problem
for an electrically sensitiveger�ing next door.
There may be other troublesome components in a solar system as well,especially
in systems that use batteries. These systems may use the batteries to power the
building during a power outage,though in most cases they are used when the
house is in a remote rural area where there is no electrical service.
Solar FMF Ilarard 2
Today's battery systems usually use technologies that are more efficient at
charging the batteries but which als emi radio-freak ency radiation. These
technologies are called Pulse-Width-Modulation (PWM),Maximum Power Point
Tracking (MPPT) and other names.
It is easy to demonstrate that the solar system generates dirty electricity. One
method is to take a simple AM radio,set the dial at the lowest frequency and hold
the radio near the solar panels or wires. A lot of static and buzzing should be
heard,which goes away when taking the radio well away from the building.
Another method is to buy a Stelzer meter and plug it into any outlet fed by the
solar system. The instrument will probably go off the scale.
It is possible to use solar-electric systems without this radiation,but they are not
suitable for most people. One will have to do like the off-grid pioneers did in the
1970s and 1980s,using 12 volt DC electricity with no inverter,and just a simple
charge controller. There are people doing it (including this author),but it is a
significant lifestyle change. Hopefully future generations of inverter design will
be better,though it will be very difficult to fully remove this radiation.
For ultra-low EMF solar systems,see http://www.eiwellspring.org/offgrid.html
Wind generators
Harvesting electricity from the wind is typically only practical for people living in
rural areas. A wind system takes up a lot of space and requires more maintenance
than a solar system. They are also noisy,which can be bothersome to sensitive
people.A few models can be mounted on a house,which is a very bad idea as it
will then magnify the vibrational noise.
Almost all residential-size windmills use an inverter to produce AC electricity. If
connected directly to the grid and placed far from the house (a minimum of 100
yards) it may be okay for an electrically sensitive person,but this has not been
tested. Even if the wind generator is placed far from the house,it could be a
problem if it is connected to the house wiring,as the wire will act as an antenna
for the inverter.
For remote houses with DC battery systems,it may be doable,but there are a
series of untested issues regarding radiation from rectifiers,voltage regulators and
transformers. This author is not aware of any EHS person who has tried it.
Wind farms are very different from residential-size wind generators. Their blades
rotate much slower, so they do not appear as noisy,but they can put out a lot of
Solar E"MP Hazard 3
inaudible vibrations (infrasound),which makes a few people sick. People with
UHS appear to be particularly susceptible.
Big wind turbines almost all use a very big inverter,which can pump a lot of dirty
electricity onto the local grid and into the soil as ground currents.
People with hypersensitivities should probably not live closer than a mile (1.6 km)
from large wind turbines.
Solar hot water systems
A solar hot water system takes the heat of the sun and warms up bath water and
sometimes even heats up a house. These systems usually have a solar collector on
the roof that heats up a liquid,which is then pumped to a storage tank for later use.
The main issue with these systems is the pump,which can be a problem for people
who are electrically sensitive. It is a small pump,and may be no more bothersome
than a refrigerator. If placed in a separate building or in a corner of a larger home,
it may be just fine. Some systems have the pump run on DC electricity directly
from a solar panel,which is not an improvement to using a regular AC pump.
Some poplar DC pumps are actually worse.
It may be possible to get solar heated water without any electricity at all. These
systems are called"thermosiphon" types,and use a storage tank mounted on the
roof,with a solar collector placed below the tank. These systems are especially
popular in third-world countries and Australia,but are best suited for climates with
only mild frosts.
What to do?
It is not easy being green and sensitive. Many "green" technologies are not safe
for people who are chemically or electrically sensitive. Some examples beyond
this article are hybrid cars and most low-energy light bulbs. So what is a green-
minded sensitive person to do? Fortunately,there are safe options,which are
simple and with no up-front investments.
Some electrical utilities are investing in large solar plants and wind farms,even in
states that traditionally have not been friendly towards the environment. Some of
these utilities may offer their customers their green electricity at a premium price,
to support the construction of more solar and wind plants. In some states, there is
no longer a monopoly on selling electricity,and there are now companies offering
electricity generated with renewable energy.
Solar F,MF Hazard 4
In areas where there is no choice,one could still purchase solar credits from
nationwide vendors. They will generate the electricity from a plant somewhere in
the country—it doesn't really matter where it is anyway. Just beware that some of
these vendors are unscrupulously selling electricity from existing plants,especially
using hydro power, so the premium does not go to any new solar or wind plants,
but directly into their pockets.
Of course,buying green electricity from the power grid does not give one the
same bragging rights as a roof filled with solar panels,but it all helps just the
same.
•
Purpose:
The purpose of this Information Bulletin is to clarify requirements of the State Building Standards Codes
(Title 24) that pertain to solar PV installations. This bulletin can serve as a reference guide for permit
applicants and enforcing agencies to clarify how state code requirements are practically applied in the
local jurisdiction. It is intended to minimize permitting uncertainty and differing interpretation regarding
specific code requirements for solar PV installations. This Information Bulletin primarily clarifies
requirements pertaining to the California Building Code and the California Residential Code, since these
codes in their current form require significant local interpretation.This Information Bulletin does not
address local regulations
The implementation of uniform standards to achieve the timely and cost-effective installation is
consistent with the California Solar Rights Act that views solar installation as a matter of statewide
concern and prohibits local jurisdictions from adopting unreasonable barriers to the installation of solar
energy systems(CA Government Code Section 65850.5).
PART I: BUILDING AND RESIDENTIAL CODE REQUIREMENTS
1. Definitions:
1.1 Solar Photovoltaic (PV) System. The total components and subsystems that, in
combination, convert solar energy into electric energy suitable for connection to utilization
load (CEC Article 690.2)
1.2 Solar photovoltaic Module. A complete, environmentally protected unit consisting of solar
cells, optics, and other components, exclusive of tracker, designed to generate do power
when exposed to sunlight(CEC Article 690.2)
California Solar Permitting Guidebook
1.3 Solar Photovoltaic (PV) Panel. A collection of modules mechanically fastened together,
wired,and designed to provide a field-installable unit(CEC Article 690.2)
1.4 Building Integrated Photovoltaics (BIPV). Photovoltaic cells, devices, modules, or modular
materials that are integrated into the outer surface or structure of a building and serve as
the outer protective surface of the building(CEC Article 690.2)
2. Structural Requirements
2.1 PV Systems Positively Anchored to the Building:
2.1.1 Exemption from structural calculations: The Building official may waive the
requirement for structural calculations for solar PV installations on top of existing
roofs if the official can readily determine that the additional weight of the new solar
PV system on the roof does not affect the structural integrity of the building. Some
Jurisdictions may have a prescriptive approach for when structural calculations can
be waived, however,that varies by the enforcing agency.
To help streamline and simplify the permitting process for roof mounted solar PV
systems, it is highly recommended that local jurisdictions develop a prescriptive
approach to meeting the structural requirements so that structural calculations are
not always required. Here are some parameters to consider under such prescriptive
approach:
- Maximum distributed weight of the solar PV system in psf
- Maximum perpendicular distance between the solar PV system and the roof
below
- Maximum concentrated load imposed by the PV panel support onto the
building's roof
- Minimum size and spacing of rafters or joists for portion of the roof that is
supporting the solar PV system
- Maximum span of rafters or joists for portion of the roof that is supporting the
solar PV system
- Anchoring requirements such as type of fasteners, minimum fastener size,
minimum embedment and minimum number of attachment points
- Any limitation on the type of building construction
2.1.2 Structural calculations: When structural calculations are required, calculations shall
demonstrate that the primary structure will support the additional vertical and
lateral loads from the panels and related equipment.
2.1.2.1 Roof dead Load: The weight of solar PV systems shall be considered in
the design of the structure. (CBC Section 1606,CRC Section R301.4)
For installation of conventional (not BIPV) solar PV panels on existing
roofs, the Building official may allow a certain percent of the code
California Solar Permitting Guidebook
required live load to be reduced to accommodate the additional weight
of the solar PV panels provided the roof design is adequate for the
concentrated loads from the solar PV panel support frames. This
allowance may vary by Jurisdiction and is generally based on the
assumption that solar PV panels will not be stepped on or used by
anyone to support any live load.
When the roof live load is allowed to be reduced, consideration should
be given to the possibility that a roof may have more than one layer of
existing roofing and the possibility of having smaller size rafters in older
buildings.
Section 3403 of the CBC states, in part, that: "Any existing gravity load-
carrying structural element for which an addition and its related
alterations cause an increase in design gravity load of more than 5
percent shall be strengthened, supplemented, replaced or otherwise
altered as needed to carry the increased load required by this code for
new structures."
2.1.2.2 Roof live load: The Building Official may allow the live load to be
reduced in the area covered by each solar PV panel when such area is
inaccessible as determined by the enforcing agency and as discussed in
Section 2.1.2.1 of this Information Bulletin. Roof surfaces not covered
by solar PV panels shall be designed for the roof live load. (CBC Section
1607,CRC R301.6)
The Building Official may determine that Live load need not be
considered for solar PV panels and associated supporting members that
are built on grade. Such interpretation is generally based on the
assumption that the solar PV panels will not be stepped on or used by
anyone to support any live load
2.1.2.3 Wind design: Calculations shall demonstrate that the solar PV panels
and associated supporting members are designed to resist wind loads.
For ballasted PV systems, see Section 2.2 of this Information Bulletin
(CBC Section 1609,CRC R301.2.1)
Note 1:The Structural Engineering Association of California is in the
process of developing a white paper titled "WIND LOADS ON LOW-
PROFILE SOLAR PHOTOVOLTAIC SYSTEMS ON FLAT ROOFS". Once
available,a link to the white paper will be included in this document.
2.1.2.4 Seismic design:Calculations shall demonstrate that the solar PV panels
and associated supporting members are designed to resist earthquake
loads. For ballasted PV systems,see Section 2.2 of this Information
Bulletin. (CBC Section 1613,CRC 301.2.2)
Note that Section 3404 of the CBC states, in part, that "Any existing
California Solar Permitting Guidebook
lateral load-carrying structural element whose demand-capacity ratios
with alteration considered is no more than 10 percent greater than its
demand-capacity ratio with the alteration ignored shall be permitted to
remain unaltered...."
2.1.2.5 For wood construction, supports shall be attached with fasteners of
sufficient length and size to achieve minimum required embedment into
solid wood taking into consideration the plywood and multiple layers of
roofing that may exist, unless otherwise approved by the enforcing
agency. (ASCE/SEI 7 Section 13.4,CRC Section R301.1.3)
2.1.2.6 Snow load: When applicable, include snow loads and loads from snow
drift(CBC Section 1608, CRC R301.2.3)
2.1.2.7 Requirements for Load Combinations: The applicable load
combinations in CBC 1605 shall be applied to all loading conditions,
including evaluating the effects of dead load to counteract wind uplift
for ballasted and anchored systems (CBG Section 1605, CRC Section
R301.1.3)
2.1.2.8 Alterations,Additions,and Repairs:Sections 3403,3404 and 3405 of the
CBC shall apply to additions, alterations and repairs associated with PV
systems. Roof structural components, their connections, additions,
alterations and repairs shall be designed to support the loads from the
PV panel support frames
2.2 Ballasted PV System: PV panels in a ballasted system are typically not attached to the roof
and rely on their weight, aerodynamics and friction to counter the effect of wind and
seismic forces. In some cases, ballasted systems have few attachment points to supplement
the friction forces. Ballasted systems have low ratios of height-to-base width or length
which makes them inherently stable against overturning.
Section 13.4 of ASCE/SEI 7-05 requires that nonstructural components and their supports be
attached (or anchored)to the structure. Ballasted solar PV systems are not addressed in the
ASCE/SEI 7 or in the building code. When approved by the enforcing agency as an
alternative material, design or method of construction pursuant to CBC Sections 12.2, 1.8.7,
or 1.11.2.4 as applicable, these systems may be unrestrained or partially restrained subject
to conditions of approval set by the enforcing agency
Note 1: Electrical connections and wiring in a ballasted should be designed to
accommodate movements within the system.
Note 2: The Structural Engineering Association of California is in the process of
developing a white paper, titled "Structural Seismic Requirements and
Commentary for Rooftop Solar Photovoltaic Systems", addressing the seismic
design of ballasted systems. Once available, a link to the white paper will be
included in this document.
California Solar Permitting Guidebook
2.3 Structural Strength of PV Panels:The structural strength of solar PV panels is not addressed
in the code.
UL 1703,Third Edition, published March 15,2002, requires that solar PV panels are tested to
withstand a superimposed load of 30lb/ft2. Therefore, all solar PV panels that are listed per
UL 1703 are considered to meet this requirement.
When used as a building component and depending on the load values that the solar PV
panels are subjected to,the enforcing agency may require a test report from an agency
recognized by the enforcing agency showing the strength of the solar PV panels.
2.4 Condition of existing roof: Solar PV systems shall not be installed on an existing roof that is
deteriorated to the point where it is not adequate as a base(this Interpretation is based on
CBC Section 1510 and CRC R907)
2.5 Pre-manufactured support systems: Pre-manufactured support systems must support the
PV system and allow the system to stay attached to the structure when exposed to wind or
seismic activity. Compliance of the PV support system with appropriate building codes
is accomplished through a design specified by a licensed engineer or architect, or
through research reports from approved sources as defined in CBC Section 1703.4.2.
Additional requirements may be imposed by the enforcing agency. (CRC Section R301.1.3,
CBC Section 1703.4:2)
3. Fire Safety Provisions
3.1 Fire/roof classification of Photovoltaic(PV)Panels
3.1.1 Solar PV Panels Installed on Top of a Building's Roof Structure:
3.1.1.1 Solar PV systems installed on top of a roof where the space between the
solar PV panels and the roof has no use and no potential use are
generally considered to be equipment. Currently, the State's Building
Standards Code maintains fire/roof classification requirements for roof
structures, but does not maintain specific requirements regarding
fire/roof classification of solar PV panels.
Since no specific requirements or guidance are provided by the State
Building Standards Code, local enforcing agencies currently determine
whether any fire/roof classification of solar PV panels is required and if
so, what fire/roof classification is required. The State Fire Marshal is
leading an effort to consider specific state code requirements for
fire/roof classification of solar panels in the current code adoption
process. Until any requirements in this area are standardized on a state
basis, agencies generally consider the following when determining any
appropriate fire/roof classification to enforce:
• UL 1703, Standard for Flat-Plate Photovoltaic Modules and Panels,
is often used for determining the fire/roof classification and
California Solar Permitting Guidebook
listing/certification of solar PV panels, This standard is not
currently listed in the CRC or the CBC but is being considered for
adoption in the 2013 State Building Standards Code. UL 1703 is
subject to change until approved as part of state code. Enforcing
agencies may consider this standard as an alternate to UL 790,
subject to approval by the Building Official. (CRC Section R902,CBC
Section 1505)
• Local enforcing agencies have used different approaches to
determine any appropriate fire/roof classification for solar PV
panels. When PV systems cover a significant portion of the roof,
some enforcing agencies have determined that the solar PV panels
mounted above the roof should match the classification of the roof
while others have determined that the panel may be of a lesser
classification based on local conditions, panel installation
configuration listing/certification and/or alternate testing
information.
• For installations in State Responsibility Areas (SRA) or High Fire
Hazard Severity Zones, additional provisions adopted by the local
enforcing agency may be applicable. Check with the enforcing
agency for any additional requirements.
3.1.1.2 Solar PV Panels Used as Roofing on an independent{standalone)
structure:Solar PV panels/modules that are designed to be the roof,and
span to structural supports,and have a use or occupancy underneath,
shall comply with the minimum fire/roof classification requirements for
roof covering as required by CRC Section R902/CBC Section 1505.An
example of this type of installation is a carport structure having solar PV
panels as the roof,
3.1.1.3 Solar PV Panels Installed as a Part of a Building's Roof Structure:Solar PV
panels installed as integrated roofing material shall comply with the
minimum fire/roof classification requirements for roof covering as
required by the current CRC Section 8902/CBC Section 1505. Example of
this type of installation is PV modules integrated into the roofing shingles
(BIPV systems).
3.1.2 Solar PV Systems installed on grade:Solar PV panels that are part of a stand alone,
ground mounted solar PV panel structures,with no use and no potential use
underneath are generally considered equipment and therefore the fire/roof
classification requirements would not apply. (Based on the definition of a roof
assembly in CRC Section R202/CBC Section 1502)
3.2 Area, height, and story limitations: Where there is a use between the solar PV panels and
the roof/grade underneath, adding such solar PV structures may constitute additional floor
area, story and/or height. Solar PV panels supported by framing that has sufficient uniformly
California Solar Permitting Guidebook
distributed and unobstructed openings throughout the top of the array (horizontal plane)to
allow heat and gases to escape, as determined by the enforcing agency, are generally
considered equipment. (CBC Section 503 and Table 503, CRC Section 1.1.3, definition of a
roof assembly in CBC Section 1502 and CRC Section R202)
3.3 Location from property line and adjacent buildings:Solar PV panels and associated framing,
with no use and no potential use between the panels and the grade underneath, are
generally treated as equipment; when not considered equipment, they may be considered a
structure and shall be located and protected based upon the code required fire separation
distance to property lines and adjacent buildings(CRC Section R302.1,CBC Section 602).
3.4 Fire proofing of structural support: Depending on the type of building, support structures of
solar PV systems that have a use or have potential for use underneath (such as carports)may
be required to be fire proofed in accordance with CBC Section 602.
2.4.1 The following installations are generally considered equipment and are not
subject to this requirement provided that the structural members are
noncombustible.
A. Stand-alone PV panel structures with no use and no potential use
underneath. (Based on definition of a roof assembly in CBC Section 1502)
B. Solar PV panels supported by framing that has sufficient uniformly
distributed and unobstructed openings throughout the top of the array
(horizontal plane) to allow heat and gases to escape, as determined by the
enforcing agency. (Based on definition of a roof assembly in CBC Section
1502)
3.4.2 Alternate designs can be considered when approved by the enforcing agency as
an alternative material, design or method of construction pursuant to CBC
Sections 1.2.2, 1.8.7,or 1.11.2.4 as applicable.
3.5 Rooftop structures: Unenclosed rooftop structures supporting solar PV systems with no use
underneath are generally not subject to CBC Section 1509.2.
3.6 Fire sprinklers: In buildings that are required to be provided with fire sprinklers, the CBC
require that all parts of the building have sprinkler coverage except where an exemption is
specifically required. Current code has no exemption for solar PV structures but here are
some guidelines(CBC 903.3):
2.6.1 Existing exemptions in the code may be used for a solar PV installation if it
meets the intent of the exemption. This will be subject to approval by the
enforcing agency.
2.6.2 Solar photovoltaic (PV) panels supported by framing that have sufficient
California Solar Permitting Guidebook
uniformly distributed and unobstructed openings throughout the top of the
array(horizontal plane)to allow heat and gases to escape, as determined by the
enforcing agency, are generally not subject to this requirement. (CBC Section
903.3.3)
2.6.3 Solar PV panels placed above the roof, with no use and no potential use
between the panels and the roof, are generally not subject to this requirement.
(Based on definition of a roof assembly in CBC Section 1502 and CRC Section
R202)
3.7 Other fire safety requirements or guidelines: The installation of solar PV systems may be
subject to additional provisions adopted by the local enforcing agency that may include the
State Fire Marshal Solar Photovoltaic Installation Guideline.Check with the enforcing
agencyfor additional requirements.The guideline can be obtained at:
hup:Hosfm.fire.ca.gov/pdf/repoLLsLsolarphotovoltaicguideline.pdf
4. Roof drainage: Roof mounted solar PV systems shall not cause excessive sagging of the roof that
results in water ponding.They shall also not block or impede drainage flows to roof drains and
scuppers. (CBC Section 1611,CRC Section R903.4)
S. Roof penetrations: All roof penetrations shall be sealed using approved methods and products to
prevent water leakage. Such methods include but not limited to caulking,roof jacks and sheet metal
flashing. (CBC Section 1503.2,CRC Section R903.2)
6. Skylights: Solar PV panels shall maintain a minimum clearance around the perimeter of skylights as
not to interfere with the function of the skylight, as determined by the enforcing agency. (CBC
Section 1205,CRC Section R303)
7. Plumbing vent,mechanical equipment and mechanical exhaust terminations: Solar PV panels shall
not obstruct or interfere with the function of plumbing vents or mechanical equipment. (CPC
Sections 901.1&906,CMC Section 304)
S. Guard rails:When required by the enforcing agency,guard rails may apply to solar PV systems. (CBC
1013.5).
9. Disabled access requirements
9.1 Non-residential,hotel, motel buildings,facilities or structures(See CBC Chapter 11B)
9.1.1 Scope. Accessibility to solar PV support structures that create a use or
occupancy shall be provided for all occupancy classifications in accordance with
Chapter 11B
9.1.2 General. When alterations, structural repairs or additions are made to
existing buildings or facilities, for the purpose of installing a solar PV system,
they shall comply with Chapter 11B
California Solar Permitting Guidebook
Note: New solar PV systems which do not create or expand a use or
occupancy and consist only of installation of the solar PV system, and
related electrical work, that does not affect disabled access
requirements for existing buildings regulated by Chapter 116 are not
considered alterations for the purpose of accessibility and should not
be subject to accessibility upgrades
9.2 Residential buildings,facilities or structures
9.2.1 Scope. New solar PV systems serving covered multifamily dwellings which
create a use or occupancy shall comply with the provisions of Chapter 11A
9.2.2 Existing buildings.The building standards contained in Chapter 11A do not apply
to the installation of solar PV systems serving privately funded multifamily
dwellings constructed for first occupancy prior to March 13, 1991
9.3 Parking
Required accessible parking spaces shall be provided and maintained in accordance with
the applicable provisions of Sections 1109A and Chapter 11B
Note: Alterations.Where parking lots,parking structures or parking facilities
are re-striped or otherwise altered to accommodate solar PV systems,
required accessible parking spaces shall be maintained or shall be
provided in accordance with the applicable provisions of Sections
1109A and 11B.
PART II. ELECTRICAL CODE REQUIREMENTS
1. Product Listing(Certification):The solar PV panel/module and other equipments used in the PV
system shall be listed/certified by a nationally recognized listing/certification agency in
accordance with the applicable standards.
2. Installation: The installation of the solar PV system must conform to the requirements of the
California Electrical Code(CEC).
3. Signage: Signage must conform to the requirements of the (CEC). Signage requirements and
location of certain equipment for solar PV systems may be subject to additional provisions
adopted by the enforcing agency that may include requirements from the State Fire Marshal
Solar Photovoltaic Installation Guideline.
PART III: LOCAL ELECTRIC UTILITY REQUIREMENTS
Check with the local utility for any incentives, interconnection, operating, and metering
requirements.
California Solar Permitting Guidebook
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THE DANGERS OF SOLAR PANEL ELECTRI Cl TY
Pai n, Serious I njury, Cancer Death
Before Outlaying Thousands of Dollars:
This website has recently been approached by people asking us why they should suddenly be suffering
unexplained health injuries and pain shortly after installing solar panel electricity systems. Injuries listed
below are only those coming directly to the notice of this website:
❑ Headaches, usually unrelievable until leaving the house.
❑ Feeling of pressure in the head.
❑ Feeling of general unwellness.
o Breathing difficulty especially at night through the nose.
❑ Respiratory disorders for the first time in a lifetime, including pneumonia.
❑ Mood Changes—e.g. a whole-of-life placid person suddenly becomes snappy.
Experience by persons associated with this website and others who have approached us in the past
suffering health injuries similar to the above immediately suggested dangerously high levels of "dirty
electricity'. On testing it was found that the levels in the solar panel victims"homes were far too high for
our GS Meters to read (maximum meter reading is 2000 GS units).
Did You Know?
Professor Emeritus Martin Graham and Power Quality Expert David Stelzer (US Court recognized expert for
electricity matters) identified "dirty electricity' as the cause of so much death, widespread injury
particularly to children and lost farm production in mid-west US4. They even had to design a special meter
to measure the problem as none existed —it is known as the Stetzerizer Microsurge Meter. I n honour of
the splendid work carried out by Graham & Stelzer in the face of big business and Government, the World
now measures dirty electricity in "GS units".
Given the correlation between GS units and electrical frequency being able to seriously damage human
health and kill, dirty electricity is considered relatively safe only if the GS units are below 50. As GS Meter
readings increase over that 50 figure, the greater the risk of cancer and serious illness. This is considered
so important in some parts of the world that Government has mandated the power utilities supply at no
more than 50 GS units.
Our research shows there is much literature about death and serious injury from "dirty electricity" as GS
units climb above the relatively safe count of 50 and that those in power do every thing they can to
prevent the knowledge being made public.
One well-known example of a cancer duster occurred at California's La Quinta Middle School. Dr Sam
Milham, the noted cancer duster investigator, and Mr Uoyd Morgan the Director of the Central Brain Tumor
Registry of the United States (CBTRUS), uncovered La Quintd's"dirty electricity" cancer duster and made it
public in the face of much opposition. I n the La Quinta Middle School investigations, the areas where
cancer dusters occurred showed GS in the multiple hundreds to beyond the Stetzerizer"s reading capacity.
C/ick here to read tha Mi/ham 6 Morgan retort
www.Ai rn-fbLi ve.cum
Until victims started approaching us in September 2011, we at "aimtolive", were not even aware that solar
electricity was dangerous. This suggests that persons pushing solar electricity for their own agendas— eg
solar panel companies, Federal Government, etc—are quite well aware of the dangers but are carefully
concealing them from public notice. Once learning of the deadly "dirty electricity" effect of solar panel
electricity, we carried out some Microsurge Meter general testing in an area of Queensland, Australia to
compare "dirty electricity" levels between various configurations of electricity used. Figures generally were
around:
❑ Power company supply only: 90-105
❑ Smaller kW solar panel installations: 480-600
❑ Larger 3-4.5 kW solar panel installations: too high for the 2000 capable Stetzerizer meter to read.
In solar panel systems connected to the electricity, the big increases in the dangerous"dirty electricity"
seem to be associated with the process of the inverter. This website has asked companies, including one
advertising on GMail, whether they;
(a) advl�se pial clients of "dirty electricity" and
(b) how do they prevent it for their particular installations.
Given that we are still waiting months later for a response or even the courtesy of an acknowledgement —
we can only presume companies know full well the injuries their products cause and don't want it known.
DON'T BE A VI CTI M
If you don't heed the advice within this website and you go ahead and install solar panel electricity without
first doing your homework, then you have only yourself to blame if you spend many thousands of dollars
and make yourself unwell or even dead.
I n the interests of your health we strongly urge:
You obtain the loan of a Stetzerizer Micxosurge meter or even buy one from a supplier:
1. Measure your home`s existing GS figures for dirty electricity on several days at different times—this
will give you a base line starting point in case you need it. Also measure some of your non-solar
neighbours and their numbers should be similar to yours if measured on the same day at roughly the same
time.
2. Measure solar or part solar electricity driven-homes near to you —if their GS figures are much greater
than yours then any difference will give you an immediate scientifically measured guideline of how much
extra risk you would expose yourself and your family to by installing solar panel electricity.
3. Ask your proposed supplier how does his/her company's product prevent increasing the levels of the
very dangerous dirty electricity. Sadly, we have noted that companies for their own reason/s are even
concealing that information from their in-field sellers so we suggest you write directly to the company CEO
and ask that person for information.
4. Possibly there are many people who may not be seriously or fatally affected by the dirty electricity of
solar panel inverters but at $10,000 to $20,000 it's a very expensive way to find out. To safeguard your
interests in case you should be one of those people badly affected, may we suggest you insist that your
supplier insert a clause into your contract similar to:
www Aim-f ot-ive.corn
"If any increase in G5 units(Dirty 6eidriaty) occurs as a result of installation of the system the company
shall, at the company expense, rectify the situation to the cuistomerl,satisfaction".
This is not an unreasonable cause and if the company won`t give you the required assurance then you
would be most wise to terminate all contact with them.
Criminality and Contract Opinion:
Where any person in a company or Government fails to disclose information known to them or reasonably
suspected may cause serious injury or death, then that person is guilty of a criminal offence, an opinion we
believe any independent legal tribunal immune to corporate dollars or Government pressure would
support. The precedent already exists in the tobacco industry over concealment of the injury and death
truth.
The shyster defence for defendants of course would be their client was unaware about "dirty electricity"
risks. To overcome this,,able-to-be-manipulated"loophole we say the Federal Government should legislate
that all solar panel electricity installations be subject to a written contract with dearly visible writing at the
start to the effect:
"It is the company's obligation to draw to your attention that solar electricity panel installations
may increase levels of dirty electricity on your wiring and this may cause serious health risks or
death to susceptible people. Before signing this contract you are advised to make your own
dirty electricity enqui ries and seek a pert advice' .
Footnotes:
I n 2000 (more than a decade ago) one country's Government, believed to be Sweden, acknowledged that
2% or 330,000 of their people were Bectrically Hyper Sensitive (EHS). This means that thousands of their
citizens have to live isolated existences away from the cause in harsh conditions, especially during winter
when they could be buried under metres of snow with little or no heating capacity.
According to Sage/San Francisco Medical Journal and more recently, research through Internet sources,
between 2% and 3% of the world's population is 9ectrically Hyper Sensitive (EHS). When you realise the
larger part of the world's population is nowhere near electricity such as in China, I ndia, Pakistan, South
Africa, South America, etc then the percentage of damaged people in the rest of the World has to be much
greater than that quoted 2 or 3 percent.
In early November 2011, we asked an accountant what he thought of solar panel electricity. His opinion
was that with a proposed installation for his own home, the O)sts/Benefits analysis was not favourable,
and so he declined to have it installed.
Disclaimer:
Comments in this document relate only to solar panel systems where there is a connection to the electricity
supply, eg inverter. It does NOT relate to panels where they only heat water passing through them, e.g.
hot water/ pool water heating.
0e, AA�,tl(rpage 1 of 1
Kyle Kritz Zoning issues
From: Tim Mueller <tim.mueller@solarplanet-us.com>
To: Wally Wernimont<wwernimo@cityofdubuque.org>
Date: 05/29/2015 12:06 PM
Subject: Zoning issues
Hey Wally,
I just wanted to pass this info on to you regarding Iowa and Wisconsin take on Solar Rights
and restrictions.
I know these sources don't address the boards issues directly but I think they point to a
common attitude that needs to play into the City's handling of this issue.
What I want the board to understand is an avg home uses goo kWh's/mon. In order to produce
that much energy from solar you need a 7 KW system. The project size I am proposing is only a
6 KW project so, God willing,the City should expect to see many more requests for this type
and size project to come across their desks.
In many cases, a ground mount is the only
tion for home owners who's roof is not conducive
op
for a roof mounted project. So, considering the tax credits are going away in 18 months for
residential projects, the likely hood of a major uptick in requests for these types of projects is
very realistic.
I really want to see them adopt a policy that embraces this movement, rather than restricting it.
Anyway, here's a few resources that the board should be familiar with.
htLp://coolice.legis.iowa.gov/Cool-ICE/default.asp?
category=billinfo&service=lowaCode&ga=83&input=564A
http://,A,ww.caioliline.org/govt/Pages/SolarRights Wl.aspx
Thanks
Tim
Tim MuellerD 0
President/Solar Planet
MAY P 9 2015
Visit our web site:
www.solar Janet-us.com PLANNING SERVICES DEPARTMENT
Click here to report this email as spam.
file:///C:/Users/kkritz/AppData/Local/Temp/XPgrpwise/5 57063 DBDBQ_DODBQ_PO 10... 06/05/2015
The average residential lot size in the flats is 25"x100", in the older sections of town it is 40"
x100" and the newer section of town is 120"x100". The average size of lots is therefore 62"x100"
or 6,200 square feet. Mr. Mueller's lot size is 27,500 square feet, it is much larger than the
average residential site. Because of this we believe that the restriction of structures taking up no
more than 40% of the property is more appropriate than the 1,000 square foot limitation.
Mr. Renne's Argument:
Mr. Renne's home is located within 60 feet of a power pole with a transformer on it and this
power poles emit at a frequency of 100 Hertz. A solar array emits radio waves at a frequency of
60 Hertz. Pictures are included.
-Mr. Renne lives 1,238 feet from Townsquare Media's radio tower in Flora Park. This tower emits
radio waves at the frequencies of 530 to 1700 kHz. As stated above, a solar array and inverter
emits radio waves_at a frequency of 60 Hertz, much lower than the radio tower. This radio tower
is located in a park and the FCC as will be sited later in this document deem all radio towers to
operate at safe frequencies unless you are the maintenance worker that would need to climb
the tower on a normal basis. Picture is included to show the distance from the radio tower to
both Mr. Renne's property and Mr. Mueller's property.
It has been said that if you want to find something on the internet you can. This means that if
you look hard enough you will find pros or cons for absolutely any subject. The key to research
on the internet is the source. Is the source a trusted, reputable, well known site?Aim to live; one
of the sites used by Mr. Renne for the health risks of solar energy cited Sage/San Francisco
Medical Journal as one of their sources. When researching the sources a site for this source
could not be found. The Milham and Morgan report cited and linked from this site is regarding a
teacher cancer cluster in a middle School in La Quinta, This study is regarding "dirty electricity"
and cancer and at no point does it state anything regarding solar energy or that this cancer
cluster was due to solar energy. It also made mention of a Dr. Graham and David Stelzer
identifying "dirty electricity", a meter is being used that measures GS units because of these two
men, but there is also a "filter" associated with the same names that has been found to be
ineffective in cleaning the electricity.
http://www emfandhealth com/Evaluation%20of%2OStetzer%2OFilters.pdf
Aimtolive.com has only a email address of bhealthv n.aimtolive.com on it. It also states that they
will attempt to read all communications but are unable to reply to all emails.
The second document from Mr. Renne also mentions Dr. Graham and Mr. Stetzer. This
document came from eiwellspring.org. This site is a site dedicated to coping with Chemical and
Electrical Hypersensitivity, the only contact information on this site is an email address for the
webmaster. It also includes the following disclaimer:
Disclaimer
The information presented on this website reflects the experiences and opinions of individuals
who wish to help others. What works for one person may not work for another. The reader must
evaluate the information in the context of his or her own situation and apply good judgment and
common sense in using this information.
None of this information can be considered medical advice. That can only come from a licensed
health professional.
In a few cases, methods described on this website may be in conflict with local building codes,
motor vehicle rules, or other laws and regulations. In some jurisdictions, only licensed
electricians can legally modify the electrical system.
It is the sole responsibility of the reader to verify legality and appropriateness of the methods
described.
In no way are any authors, or anyone associated with this website, responsible for any outcome
or result from using any of the presented information. No liability, direct or indirect, is assumed.
Our response:
According to Massachusetts Department of Energy Resources/ Massachusetts Department of
Environmental Protection and Massachusetts Clean Energy Center in their Clean Energy
Results study when asked the question: "What, if any, health risks do the electric and magnetic
fields (EMF) from solar panels and other components of solar PV arrays post?" noted that:
"Electric and magnetic fields are a normal part of life in the modern world. PV arrays generate
EMF in the same extremely low frequency (ELF) range as electrical appliances and wiring found
in most homes and buildings. The average daily background exposure to magnetic fields is
estimated to be around one mG (milligauss), but can vary considerably depending on a person's
exposure to EMF from household electrical devices and wiring. The lowest exposure level that
has been potentially associated with a health effect is three mG."
It goes on to say, "Solar PV panels, inverters and other components that make up solar PV
arrays produce extremely low frequency EMF when generating and transmitting electricity. The
extremely low frequency EMF from PV arrays is the same as the EMF people are exposed to
from household electrical appliances, wiring in buildings, and power transmission lines (all at the
power frequency of 60 hertz). EMF produced by cell phones, radios and microwaves is at much
higher frequencies (30,000 hertz and above).
And finally; "Exposure to magnetic fields greater than 1000 mG is not recommended for people
with pacemakers or defibrillators (ACGIH, 2001)." The resources for this study include:
American Conference of Government Industrial Hygienist (ACGIH), Electric Power Research
Institute (EPRI), National Cancer Institute (NCI), National Institute of Environmental Health
Science (NIEHS), and World Health Organization (WHO).
Electromagnetic Radiation Spectrum Quantum(Photon)Energy(OVi
10.2 100 102 104 108 108 1053 101'
wavelength(Metres)
1 B 108 10+ 102 100 1tr2 10' 10'0 10.8 io-0 10'11 10-r" 10-i0 10.13
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icrowave
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rb!e Optics XRays
'rdaBoder Hea(
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Frequency(I 1€)
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163 Cr I ZEN 11-11
On this graph, the Frequency at which a solar array operates would be lower than Power
Cables at the far left of the spectrum. Dangerous frequency start at the array on the far right of
the spectrum starting at Ultra Violet rays and includes X Rays, Gamma Rays and Cosmic Rays.
Princeton University also did a study and found that other than the manufacturing of the solar
panels, "Overall the health impact of solar power is likely to be far less than that of any of the
fossil fuels."
From the FCC:
WHAT LEVELS ARE SAFE FOR EXPOSURE TO RF ENERGY?
Exposure standards for radiofrequency energy have been developed by various organizations
and countries. These standards recommend safe levels of exposure for both the general public
and for workers. In the United States, the FCC has adopted and used recognized safety
guidelines for evaluating RF environmental exposure since 1985. Federal health and safety
agencies, such as the EPA, FDA, the National Institute for Occupational Safety and Health
(NIOSH) and the Occupational Safety and Health Administration (OSHA) have also been
involved in monitoring and investigating issues related to RF exposure.
The FCC guidelines for human exposure to RF electromagnetic fields were derived from the
recommendations of two expert organizations, the National Council on Radiation Protection and
Measurements (NCRP) and the Institute of Electrical and Electronics Engineers (IEEE). Both
the NCRP exposure criteria and the IEEE standard were developed by expert scientists and
engineers after extensive reviews of the scientific literature related to RF biological effects. The
exposure guidelines are based on thresholds for known adverse effects, and they incorporate
prudent margins of safety. In adopting the most recent RF exposure guidelines, the FCC
consulted with the EPA, FDA, OSHA and NIOSH, and obtained their support for the guidelines
that the FCC is using.
Many countries in Europe and elsewhere use exposure guidelines developed by the
International Commission on Non-Ionizing Radiation Protection (ICNIRP). The ICNIRP safety
limits are generally similar to those of the NCRP and IEEE, with a few exceptions. For example,
ICNIRP recommends somewhat different exposure levels in the lower and upper frequency
ranges and for localized exposure due to such devices as hand-held cellular telephones. One
of the goals of the WHO EMF Project (see above) is to provide a framework for international
harmonization of RF safety standards. The NCRP, IEEE and ICNIRP exposure guidelines
identify the same threshold level at which harmful biological effects may occur, and the values
for Maximum Permissible Exposure (MPE) recommended for electric and magnetic field
strength and power density in both documents are based on this level. The threshold level is a
Specific Absorption Rate (SAR) value for the whole body of 4 watts per kilogram (4 W/kg).
In addition, the NCRP, IEEE and ICNIRP guidelines for maximum permissible exposure are
different for different transmitting frequencies. This is due to the finding (discussed above)that
whole-body human absorption of RF energy varies with the frequency of the RF signal. The
most restrictive limits on whole-body exposure are in the frequency range of 30-300 MHz where
the human body absorbs RF energy most efficiently when the whole body is exposed. For
devices that only expose part of the body, such as mobile phones, different exposure limits are
specified (see below).
The exposure limits used by the FCC are expressed in terms of SAR, electric and magnetic field
strength and power density for transmitters operating at frequencies from 300 kHz to 100 GHz.
The actual values can be found in either of two informational bulletins available at this Web site
(OET Bulletin 56 orOET Bulletin 65), see listing for"OET Safety Bulletins."
ARE EMISSIONS FROM RADIO AND TELEVISION BROADCAST ANTENNAS SAFE?
Radio and television broadcast stations transmit their signals via RF electromagnetic waves.
There are thousands of radio and TV stations on the air in the United States. Broadcast
stations transmit at various RF frequencies, depending on the channel, ranging from about 540
kHz for AM radio up to about 800 MHz for UHF television stations. Frequencies for FM radio
and VHF television lie in between these two extremes. Broadcast transmitter power levels
range from a few watts to more than 100,000 watts. Some of these transmission systems can
be a significant source of RF energy in the local environment, so the FCC requires that
broadcast stations submit evidence of compliance with FCC RF guidelines.
The amount of RF energy to which the public or workers might be exposed as a result of
broadcast antennas depends on several factors, including the type of station, design
characteristics of the antenna being used, power transmitted to the antenna, height of the
antenna and distance from the antenna. Note that the power normally quoted for FM and TV
broadcast transmitters is the "effective radiated power" or ERP not the actual transmitter power
mentioned above. ERP is the transmitter power delivered to the antenna multiplied by the
directivity or gain of the antenna. Since high gain antennas direct most of the RF energy toward
the horizon and not toward the ground, high ERP transmission systems such as used for UHF-
TV broadcast tend to have less ground level field intensity near the station than FM radio
broadcast systems with lower ERP and gain values. Also, since energy at some frequencies is
absorbed by the human body more readily than at other frequencies, both the frequency of the
transmitted signal and its intensity is important. Calculations can be performed to predict what
field intensity levels would exist at various distances from an antenna.
Public access to broadcasting antennas is normally restricted so that individuals cannot be
exposed to high-level fields that might exist near antennas. Measurements made by the FCC,
EPA and others have shown that ambient RF radiation levels in inhabited areas near
broadcasting facilities are typically well below the exposure levels recommended by current
standards and guidelines. There have been a few situations around the country where RF
levels in publicly accessible areas have been found to be higher than those recommended in
applicable safety standards. As they have been identified, the FCC has required that stations at
those facilities promptly bring their combined operations into compliance with our guidelines.
Thus, despite the relatively high operating powers of many broadcast stations, such cases are
unusual, and members of the general public are unlikely to be exposed to RF levels from
broadcast towers that exceed FCC limits
Antenna maintenance workers are occasionally required to climb antenna structures for such
purposes as painting, repairs, or lamp replacement. Both the EPA and OSHA have reported
that in such cases it is possible for a worker to be exposed to high levels of RF energy if work is
performed on an active tower or in areas immediately surrounding a radiating antenna.
Therefore, precautions should be taken to ensure that maintenance personnel are not exposed
to unsafe RF fields.
This information can be found on the FCC website at https://transition.fcc.gov/oetlrfsafety/rf-
fags.html#Q28
As stated earlier in this document, Solar Arrays emit radios waves at 60 hertz, much lower than
that of the radio towers or even the power line.
The FDA regulates the emissions from Microwaves and other household devices and states the
following:
Description
Microwave ovens.heat food using microwaves, a form of electromagnetic radiation similar to
radio waves. Microwaves have three characteristics that allow them to be used in cooking: they
are reflected by metal; they pass through glass, paper, plastic, and similar materials; and they
are absorbed by foods.
A device called a magnetron inside the oven produces microwaves. The microwaves reflect off
the metal interior of the oven and cause the water molecules in food to vibrate. This vibration
results in friction between molecules, which produces heat that cooks the food.
Risks/Benefits
I Top
Microwaves are non-ionizing radiation, so they do not have the same risks as x-rays or other
types of ionizing radiation. But, microwave radiation can heat body tissues the same way it
heats food. Exposure to high levels of microwaves can cause skin burns or cataracts. Less is
known about what happens to people exposed to low levels of microwaves.
To ensure that microwave ovens are safe, manufacturers are required to certify that their
microwave oven products meet the strict radiation safety standard created and enforced by the
FDA.
Microwave energy will not leak from a microwave in good condition. A damaged microwave
oven may present a risk of microwave energy leaks. Contact your microwave's manufacturer for
assistance if your microwave oven has damage to its door hinges, latches, or seals, or if the
door does not open or close properly.
Description
Video display products that contain cathode ray tubes (CRTs) can give off x-rays. The CRT is a
specialized vacuum tube that receives and displays images on an electronic screen. Most
modern computers monitors and televisions (TVs) today use liquid crystal display (LCD), Light-
emitting diodes (LED), or plasma.
In the early 1960s, some TVs with CRTs were found to emit excessive x-radiation, and a federal
performance standard was created to protect the public from this hazard. Today, electronic
technology for TVs and computer monitors with CRTs has changed so drastically that the level
of risk of x-ray exposure is almost non-existent. Manufacturers of products that use CRTs must
certify that their products comply with the federal performance standard for the life of the
product.
I Toa
Risks/Benefits
TV receivers and computer monitors containing CRTs no longer pose a risk of emitting
excessive x-radiation. Since the creation of the federal performance standard, the FDA has
tested hundreds of TV receivers and computer monitors and rarely encountered any that were
unsafe.
This information can be found at: http://www.fda.gov/Radiation-
EmittingProducts/Radiation Emitting ProductsandProcedures/HomeBusinessandEntertain ment/d
efault.htm
Waco School District has installed a ground mount solar array behind their elementary school in
Crawfordsville Iowa as well as a ground mount array next to the football field at their high school
in Wayland Iowa. Children are present during operation of these panels for nine months out of
the year. One would assume that a school district would do their due diligence and research any
risk to children that may be involved.
Pictures of the Waco School districts current arrays are included.
NEC 2014:
We are attaching the code regarding Solar Photovoltaic (PV) Systems so that a review of the
electrical safety can be confirmed. An addition to this code beginning on 6/9/2015 will include
plastic mesh being installed on the back of all ground mounted solar arrays to deter anyone
from attempting to tamper with the array in anyway. This will obviously address the issue of
children from the park attempting to climb on the array.
Our Work:
Attached are pictures of the ground mounts we have installed to this point, as well as a picture
of where the proposed array will be located on the Mueller property. This array will have hostas
and other shade loving plants arranged under it and will have no effect on the greenspace.
Our Certifications:
Our Certifications are also attached for review.
In conclusion; the organizations and websites citing that the radio and magnetic waves emitted
from a solar array and its components are within a safe level are extremely reliable. The
research on the subject is quite extensive and ongoing. Using a cell phone or a laptop seem to
be more dangerous than installing a solar array.
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CLEAN ENERGYRESULTS
,•-•CLEANENERYRESULTS
Questions & Answers
Ground-Mounted Solar Photovoltaic Systems
Westford Solar Park,photo courtesy of EEA
June 2015
Massachusetts Department of Energy Resources
Massachusetts Department of Environmental Protection
Massachusetts Clean Energy Center
Table of Contents
Background......................................................................................................................3
HazardousMaterials......................................................................................................5
End-of-Life/Decommissioning......................................................................................7
Ambient Temperature („Heat Island")........................................................................9
Electric and Magnetic Fields (EMF)............................................................................10
PropertyValues.............................................................................................................13
Public Safety (including fires)......................................................................................14
Historic Preservation....................................................................................................16
Noise...............................................................................................................................18
Water-Related Impacts................................................................................................20
Glare...............................................................................................................................22
Endangered Species and Natural Heritage...............................................................23
2
Background
Encouraging increased use of solar photovoltaic (PV)technology,which converts sunlight directly into
electricity, is a key priority for state clean energy efforts.The environmental benefits of solar PV abound.
Unlike conventional fossil fuel power generation (such as coal, gas and oil),generating electricity with
ground-mounted solar PV involves no moving parts, uses no water, and produces no direct emissions of
climate-warming greenhouse gases.
Solar PV environmental and energy benefits, combined with strong incentives available for solar
projects, have significantly increased the use of this technology recently.The Commonwealth's vibrant
solar industry has a variety of ownership and financing options for Massachusetts residents and
businesses looking to install solar PV systems. Purchasing a solar PV system generally involves upfront
installation and equipment costs, but there are significant upfront and production-based incentives7.
As the Massachusetts clean energy sector grows,the Baker Administration is working to ensure that
solar PV and other clean energy technologies are sited in a way that is most protective of human health
and the environment, and minimizes impacts on scenic, natural, and historic resources.
Purpose of Guide
This guide is intended to help local decision-makers and community members answer con; n
questions about ground-mounted solar PV developme4. Ground-mounted solar PV has many proven
advantages and there has been a steady growth of well received projects in the Commonwealth.
However,these systems are still relatively new and unfamiliar additions to our physical landscape.
This guide focuses on questions that have been raised concerning the installation and operation of
ground-mounted solar PV projects. It provides summaries and links to existing research and studies that
can help understand solar PV technology in general and ground-mounted solar in particular.
Solar PV panels can and are of course also installed on buildings', carports or light poles. This guide
focuses on ground-mounted systems since most questions relate to this type of solar installation.
Developed through the partnership of the Massachusetts Department of Energy Resources (DOER),the
Massachusetts Department of Environmental Protection (MassDEP), and the Massachusetts Clean
Energy Center(MassCEQ, this guide draws from existing recent literature in the United States and
abroad and is not the result of new original scientific studies.The text was reviewed by the National
Renewable Energy Laboratory(NREL).
As more or new information becomes available,the guide will be updated and expanded accordingly.
For a comprehensive overview,start at http://masscec.com/index.cfm/page/Solar-PV/pid/12584
'For an overview of the multiple options for siting PV and buildings in the same footprint,see the Solar Ready
Buildings Planning Guide, NREL,2009.
3
Solar PV Projects Are Sited Locally
The siting authority for solar PV projects resides at the local-not the state-level. One purpose of this
guide is to inform and facilitate local efforts to expand clean energy generation in a sustainable way, and
provide a consolidated source of existing research and information that addresses common questions
faced by communities.
As part of the Green Communities Act of 2008, DOER and the Massachusetts Executive Office of Energy
and Environmental Affairs(EOEEA)developed a model zoning by-law/ordinance called "as-of-right
siting"that does not require a special permit. It is designed to help communities considering adoption
of zoning for siting of large-scale solar.This model zoning by-law/ordinance provides standards for the
placement,design, construction, operation, monitoring,modification and removal of new large-scale
ground-mounted solar PV installations.The latest version of the model by-law was published in
December 20143. It provides useful information that will not be repeated extensively in this guide.
Consider Impacts of Other Possible Developments at Site
Use of land for the purpose of solar photovoltaic power generation should be compatible with most
other types of land usage. However, DOER strongly discourages designating locations that require
significant tree cutting because of the important water management, cooling and climate benefits trees
provide. DOER encourages designating locations in industrial and commercial districts, or on vacant,
disturbed land. `
When assessing the impact of new ground-mounted solar arrays, communities and other stakeholders
should carefully consider other types of development that might take place in a particular location if
there was no solar installation. Stakeholders should bear in mind the higher or lower impacts that those
alternatives might have in terms of noise, air pollution or landscape. These alternative impacts fall
outside the scope of this guide, but are relevant when looking at individual projects.
3 http//www mass gov/eea/docs/doer/green-communities/grant-program/model-solar-zoning.pdf
4
Hazardous Materials
The Question:What, if any, health risks do chemicals used to manufacture solar panels and other
devices used in solar PV arrays pose if they are released into the environment?
Bottom Line: Because PV panel materials are enclosed,and don't mix with water or vaporize into the
air,there is little, if any, risk of chemical releases to the environment during normal use.The most
common type of PV panel is made of tempered glass, which is quite strong. They pass hail tests, and are
regularly installed in Arctic and Antarctic conditions. Only in the unlikely event of a sufficiently hot fire is
there a slight chance that chemicals could be released.This is unlikely because most residential fires are
not hot enough to melt PV components and PV systems must conform to state and federal fire safety,
electrical and building codes.
Transformers used at PV installations,that are similar to the ones used throughout the electricity
distribution system in cities and towns, have the potential to release chemicals if they leak or catch fire.
Transformer coolants containing halogens have some potential for toxic releases to the air if combusted.
However, modern transformers typically use non-toxic coolants,such as mineral oils. Potential releases
from transformers using these coolants at PV installations are not expected to present a risk to human
health.
More Information: Ground-mounted PV solar arrays are typically made up of panels of silicon solar cells
covered by a thin layer of protective glass, which is attached to an inert solid underlying substance (or
"substrate"). While the vast majority of PV panels currently in use are made of silicon, certain types of
solar cells may contain cadmium telluride (CdTe), copper indium diselenide (CIS), and gallium arsenide
(GaAs).
All solar panel materials, including the chemicals noted above, are contained in a solid matrix, insoluble
and non-volatile at ambient conditions, and enclosed.Therefore, releases to the ground from leaching,
to the air from volatilization during use, or from panel breakage,are not a concern. Particulate
emissions could only occur if the materials were ground to a fine dust, but there is no realistic scenario
for this. Panels exposed to extremely high heat could emit vapors and particulates from PV panel
components to the air. However, researchers have concluded that the potential for emissions derived
from PV components during typical fires is limited given the relatively short-duration of most fires and
the high melting point(>1000 degrees Celsius) of PV materials compared to the roof level temperatures
typically observed during residential fires(800-900 degrees Celsius). In the rare instance where a solar
panel might be subject to higher temperatures,the silicon and other chemicals that comprise the solar
panel would likely bind to the glass that covers the PV cells and be retained there.
Release of any toxic materials from solid state inverters is also unlikely provided appropriate electrical
and installation requirements are followed. For more information on public safety and fire, see the
Public Safety section of this document.
We should also note that usually the rain is sufficient to keep the panels clean, so no extra cleaning in
which cleaning products might be used, is necessary.
5
Resources:
Fthenakis, V.M., Overview of Potential Hazards in Practical Handbook of Photovoltaics:Fundamentals
and Applications, General editors T. Markvart and L. Castaner, to be published by Elsevier in 2003.
Fthenakis, V.M. Life cycle impact analysis of cadmium in CdTe PV production. Renewable and
Sustainable Energy Reviews 8, 303-334, 2004.
Fthenakis V.M., Kim H.C.,Colli A.,and Kirchsteiger C., Evaluation of Risks in the Life Cycle of
Photovoltaics in a Comparative Context, 21st European Photovoltaic Solar Energy Conference, Dresden,
Germany, 4-8 September 2006.
Moskowitz P. and Fthenakis V.,Toxic materials released from photovoltaic modules during fires; health
risks, Solar Cells, 29, 63-71, 1990.
Sherwani, A.F., Usmani,l.A., &Varun. Life cycle assessment of solar PV based electricity generation
systems: A review. Renewable and Sustainable Energy Reviews. 14, 540-544, 2010.
Zayed,l; Philippe,S (2009-08). "Acute Oral and Inhalation Toxicities in Rats With Cadmium Telluride"
(PDF).International journal of toxicology(International Journal of Toxicology) 28 (4): 259-65.
doi:10.1177/1091581809337630. PMID 19636069. htttr//ijt sagepub con/cgi/contenVshort/28/4/259.
6
End-of-Life/Decommissioning
Question: How do I manage solar panels after they are decommissioned and no longer in use? Can they
be recycled and do hazardous waste disposal requirements apply?
Bottom Line: As more solar panels are decommissioned interest in recycling the panels has increased in
Europe and the U.S. Massachusetts regulations ensure proper disposal and recycling of panels if they
have components that constitute solid or hazardous waste under state regulations.
More information:The average life of solar PV panels can be 20-30 years (or longer) after initial
installation. PV cells typically lose about 0.5%of their energy production capacity per year. At the time
of decommissioning, panels may be reused, recycled or disposed.Since widespread use of solar PV is
recent in Massachusetts, only a small percentage of solar panels in use in the state have had to be
replaced due to damage or reached the end of their useful lifetime. A significant increase in the amount
of end-of-life PV modules is expected over the next few decades.
When solar panels are decommissioned and discarded, state rules require that panel disposal be
"properly managed" pursuant to the Massachusetts hazardous waste regulations, 310 CMR 30.000.
There are many different types of solar panels used in ground-mounted or roof mounted solar PV
systems; some of these panels have components that may require special hazardous waste disposal or
recycling. Solar module manufacturers typically provide a list of materials used in the manufacturing of
their product, which may be used to determine the proper disposal requirements at the time of
decommissioning. Under the hazardous waste regulations,the burden is on the generator of the panels
to determine if the waste being generated (the solar panels) is hazardous or not. This determination can
be made using"knowledge" (i.e. an MSDS sheet listing the materials used in manufacture of the panels)
or testing(i.e.the Toxicity Characteristic Leaching Procedure—TCLP).
If a panel is tested and passes TCLP then it is regulated as a solid waste; if it fails TCLP then it is regulated
as a hazardous waste.
However, if the solar panel is determined to be hazardous due solely to the presence of metal-bearing
circuit boards,the panels may be conditionally exempt from the hazardous waste regulations if destined
for recycling. See 310 CMR 30.202(5)(d)-(e) in the Mass. Hazardous Waste Regulations.4
People who lease land for solar projects are encouraged to include end-of-life panel management as
part of the lease. In cases where panels are purchased, owners need to determine whether the end-of
4(5)The following materials are not subject to 310 CMR 30.200,or any other provision of 310
CMR 30.000:
(d)Whole used circuit boards being recycled provided they are free of mercury switches,
mercury relays, nickel-cadmium batteries,or lithium batteries.
(e)Shredded circuit boards being recycled provided that they are:
1. managed in containers sufficient to prevent a release to the environment prior to
recovery; and,
2.free of mercury switches, mercury relays and nickel-cadmium batteries and lithium
batteries.
life panels are a solid or hazardous waste and dispose or recycle the panels appropriately.
Massachusetts regulations require testing of waste before disposal.
Because of the various materials used to produce solar panels(such as metal and glass), interest in
recycling of solar modules has grown.Throughout Europe, a not-for-profit association (PV Cycle) is
managing a voluntary collection and recycling program for end-of-life PV modules.The American
photovoltaic industry is not required by state or federal regulation to recycle its products, but several
solar companies are starting to recycle on a voluntary basis. Some manufacturers are offering end-of-life
recycling options and independent companies looking to recycle solar modules are growing.This allows
for the recycling of the PV panels and prevents issues with the hazardous materials. Currently,the
California Department of Toxic Substances Control is considering standards for the management of solar
PV panels at the end of their use.
DOER's model zoning provides language on requirements for abandonment and decommissioning of
solar panels for use by local officials considering local approvals for these projects.
Resources
End-of-life PV:then what? - Recycling solar PV panels
http //www renewableenergyfocus com/view/3005/end-of-life-pv-then-what-recycling-solar-pv-panels/
MassDEP Hazardous Waste Regulations 310 CMR 30.000
http//www mass gov/eea/agencies/massdep/recycle/regulations/310-cmr-30-OOO.html
PV Cycle, Europe: http://www.pvcycle.org/
California Department of Toxic Substances Control, Proposed Standards for the Management of
Hazardous Waste Solar Modules,
http://www.dtsc.ca.gov/LawsReRsPolicies/Regs/Reg Exempt HW Solar Panels.cfm
8
Ambient Temperature ("Heat Island")
TPoe Question: Does the presence of ground-mounted solar PV arrays cause higher ambient
temperatures in the surrounding neighborhood (i.e., the "heat island" effect)?
Bottom Line:All available evidence indicates that there is no solar"heat island" effect caused by the
functioning of solar arrays. Cutting shade trees for solar PV might increase the need for cooling if those
trees were shading buildings.This is primarily a concern in town centers and residential areas(locations
where large ground-mounted PV is not encouraged) and is a potential impact of any development
activity that requires tree-cutting.
More Information: All available evidence indicates that there is no solar"heat island" effect caused by
the functioning of solar arrays. Solar panels absorb photons from direct sunlight and convert it to
electricity.This minimizes the likelihood of substantially changing temperatures at the site or the
surrounding neighborhood. For an area with no PV system, solar energy impacting the ground is either
reflected or absorbed.There is no research to support heat production from the solar panels
themselves.
Sunpower, a private solar manufacturer, conducted a study on the impact of solar.PV on the local
temperature,and concluded that a solar PV array can absorb a higher percentage of heat than a
forested parcel of land without an array.The study points out that while solar PV modules can reach
high operating temperatures up to 120 degrees Fahrenheit,they are thin and lightweight and therefore
do not store a large amount of heat. Because of this, and the fact that panels are also shown to cool to
ambient air temperature shortly after the sun sets,the Sunpower study concludes that the area
surrounding a large-scale solar array is unlikely to experience a net heating change from the panels.
If trees are removed that were previously shading a building,that building could get warmer in full
sunshine than when the trees were shading it. The June 1, 2011 tornado that ripped through Western
Massachusetts created an opportunity to empirically measure the effects of the loss of neighborhood
trees on temperatures and air humidity in the streets.A report by the U.S. Department of Agriculture
Forest Service concluded that daily mean morning and afternoon temperatures were typically greater in
the tornado-impacted neighborhood in Springfield, Massachusetts than in the unaffected neighborhood
and forest sites, but were similar at night. Residents noted increased use of air-conditioning units and an
overall increase in energy costs in July and August of 2011.
Resources:
SUNPOWER, Impact of PV Systems on Local Temperature,July 2010
USDA Forest Services report: http://www.regreenspringfield.com/wp-
content/up loads/2011/11/tornado%20cl i mate%20report%203.pdf
9
Electric and Magnetic Fields (EMF)
The Question: What, if any, health risks do the electric and magnetic fields.(EMF)from solar panels aRtd
other components of solar PV arrays posed
Bottom Line: Electric and magnetic fields are a normal part of life in the modern world. PV arrays
generate EMF in the same extremely low frequency (ELF) range as electrical appliances and wiring found
in most homes and buildings.The average daily background exposure to magnetic fields is estimated to
be around one mG (milligauss—the unit used to measure magnetic field strength), but can vary
considerably depending on a person's exposure to EMF from household electrical devices and wiring.
The lowest exposure level that has been potentially associated with a health effect is three mG.
Measurements at three commercial PV arrays in Massachusetts demonstrated that their contributions
to off-site EMF exposures were low (less than 0.5 mG at the site boundary),which is consistent with the
drop off of EMF strength based on distance from the source.
More Information: Solar PV panels, inverters and other components that make up solar PV arrays
produce extremely low frequency EMF when generating and transmitting electricity.The extremely low
frequency EMF from PV arrays is the same as the EMF people are exposed to from household electrical
appliances,wiring in buildings, and power transmission lines (all atthe powerfrequency of 60 hertz).
EMF produced by cell phones, radios and microwaves is at much higher frequencies (30,000 hertz and
above).
Electric fields are present when a device is connected to a power source, but are shielded or blocked by
common materials, resulting in low potential for exposures.On the other hand, magnetic fields,which
are only generated when a device is turned on, are not easily shielded and pass through most objects,
resulting in greater potential for exposure. Both types of fields are strongest at the source and their
strength decreases rapidly as the distance from the source increases. For example,the magnetic field
from a vacuum cleaner six inches away from the motor is 300 mG and decreases to two mG three feet
away. People are exposed to EM F during normal use of electricity and exposure varies greatly over time,
depending on the distance to various household appliances and the length of time they are on.The daily
average background level of magnetic fields for US residents is one mG.
EMF from PV Arrays:Solar PV panels produce low levels of extremely low frequency(ELF) EMF,with
measured field strengths of less than one mG three inches from the panel. Solar PV power inverters,
transformers and conduits generate higher levels of ELF-EMF.The amount of ELF-EMF is proportional to
the electrical capacity of the inverter and is greater when more current (electricity) is flowing through a
power line.
In a study of two PV arrays (using 10-20 IkW invertors) in Kerman and Davis, California,the magnetic field
was highest at the inverters and transformers, but decreased rapidly to less than one mG within 50 feet
of the units,well within the boundary of the PV array (Chang and Jennings 1994).This data indicates
that extremely low frequency EMF field strengths at residences near systems of this size would be below
the typical levels experienced by most people at home.The highest extremely low frequency EMF (up to
1,050 mG)was found next to an inverter unit at the point of entry of the electrical conduits. Even this
10
value is less than the extremely low frequency EMF reported for some common household devices such
as an electric can opener with a maximum of 1500 mG at 6 inches.
In a recent study of three ground mounted PV arrays in Massachusetts,the above results were
confirmed. The PV arrays had a capacity range of 1 to 3.5 MW. Magnetic field levels along the PV array
site boundary were in the very low range of 0.2 to 0.4 mG. Magnetic fields at 3 to 7 feet from the
inverters ranged from 500 to 150 mG. At a distance of 150 feet from the inverters,these fields dropped
back to very low levels of 0,5 mG or less, and in many cases to much less than background levels (0.2
mG).
Potential Health Effects: Four research studies have reported an association between three to four mG
EMF exposure and childhood leukemia,while 11 other studies have not.These studies are inconsistent
and do not demonstrate a causal link that would trigger a World Health Organization (WHO) designation
of EMF as a possible carcinogens.Studies looking at other cancers in humans and animals have not
found evidence of a link to residential ELF-EMF exposure.
Reference Exposure Levels:To protect the general public from health effects from short-term high level
magnetic fields,the International Commission on Non-Ionizing Radiation Protection (ICNIRP, 2010)
advised an exposure limit for extremely low frequency magnetic fields at 2000 mG. ICNIRP determined
that the evidence on the impact of long-term exposure to low level magnetic fields was too uncertain to
use to set a guideline. Guidelines for the magnetic field allowed at the edge of transmission line right-of-
ways have been set at 200 mG by Florida and New York. Exposure to magnetic fields greater than 1000
mG is not recommended for people with pacemakers or defibrillators (ACGIH, 2001).
Resources:
American Conference of Government Industrial Hygienist(ACGIH). 2001. as cited in NIEHS 2002.
Chang, G1 and Jennings, C. 1994. Magnetic field survey at PG&E photovoltaic sites. PG&E R&D Report
007,5-94-6.
Electric Power Research Institute(EPRI). 2012. EMF and your health.
http://my.epri.com/portal/server.pt?Abstract id=000000000001023105.
International Commission on Non-Ionizing Radiation Protection (ICNIRP).2010. ICNIRP Guidelines for
limiting exposure to time-varying electric and magnetic fields (1 Hz-100kHz). Health Physics 99(6):818-
836.
National Cancer Institute(NCI).2005. Magnetic Field Exposure and Cancer: Questions and Answers. U.S.
Department of Health and Human Services, National Institutes of Health. Available
http•//www cancer gov/cancertopics/factsheet/Risk/magnetic-fields accessed May 14,2012.
5 WHO has designated ELF-EMF as a possible carcinogen.The use of the label "possible carcinogen" indicates that
there is not enough evidence to designate ELF-EMF as a"probable carcinogen"or"human carcinogen,"the two
indicators of higher potential for being carcinogenic in humans.
11
National Institute of Environmental Health Science (NIEHS) 2002. Electric and Magnetic Fields Associated
with the Use of Electric Power: Questions and Answers.Available
http:/Lwww.niehs.nih.gov/health/assets/docs p z/results of emf research emf questions answers b
ooklet.pdf, accessed May 11,2012.
National Institute of Environmental Health Science (NIEHS) web page on EMF. Available
http://www.niehs.nih.gov/health/topics/agents/emf/, accessed May 11, 2012.
Oregon Department of Transportation (Oregon DOT).Scaling public concerns of electromagnetic fields
produced by solar photovoltaic arrays. Produced by Good Company for ODOT for the West Linn Solar
Highway Project. Available www.oregon.gov/ODOT/HWY/OIPP/docs/emfconcerns.pdf.
World Health Organization (WHO). 2007. Electromagnetic fields and public health: Exposure to
extremely low frequency fields. Fact sheet N0322.June 2007.Available
http•//www.who.int/medlacentre/factsheets/fs322/en/index.htm], accessed May 16, 2012.This fact
sheet provides a short summary of the in-depth review documented in the WHO 2007, Environmental
Health Criteria 238.Available http://www.who.int/peh-emf/publications/elf ehc/en/index.html.
12
Property Values
Question: How do ground-mounted solar PV arrays adjacent to residential neighborhoods influence the
property values in those neighborhoods?
Bottom Line: No research was found specific to ground-mounted solar PV and property values.
Residential property value research on roof-mounted solar PV and wind turbines illustrates no evidence
of devaluation of homes in the area. Municipalities that adopt zoning for solar facilities may want to
consider encouraging project developers to include screening vegetation along site borders to minimize
visual impacts on surrounding neighborhoods.
More Information:A review of literature nationwide shows little evidence that solar arrays influence
nearby property values,An analysis focused on roof-mounted solar PV done by the U.S. Department of
Energy Lawrence Berkeley National Laboratory concludes that household solar installation actually
increases home property values.This research analyzes a large dataset of California homes that sold
from 2000 through mid-2009 with PV installed.Across a large number of repeat sales model
specifications and robustness tests,the analysis finds strong evidence that California homes with PV
systems have sold for a premium over comparable homes without PV systems.
Resources:
An Analysis of the Effects of Residential Photovoltaic Energy Systems on Home Sales Prices in California
http://er6p.lbl.gov/sites/all/files/Ibnl-4476e.pdf
13
Public Safety (including fires)
Question: What public safety issues arise from people's (including children) access to areas where solar
arrays are installed? Can electrical and other equipment associated with solar projects cause electrical
fires?
Bottom Line: Large-scale ground-mounted arrays are typically enclosed by fencing.This prevents
children and the general public from coming into contact with the installations,thus preventing unsafe
situations.The National Electric Code has mandatory requirements to promote the electrical safety of
solar PV arrays. Emergency personnel responding to potential emergencies at a solar PV site face the
most risk, but the solar industry and firefighters provide training and education for emergency
personnel to ensure that the proper safety precautions are taken.
More Information:The National Electric Code has mandatory requirements for the electrical safety of
solar PV arrays. To protect against intruders, Article 690 of the National Electric Code covers the safety
standards for solar PV installation and requires that conductors installed as part of solar PV be "not
readily accessible". With a large-scale ground-mounted array,a fence is typically installed around the
system to prevent intruders. Some communities have solar PV or signage by-laws that require
identification of the system owner and 24-hour emergency contact information.
DOER'S Model by-Law/ordinance requires owners of solar PV facilities to provide a copy of the project
summary, electrical schematic, and site plan to the local fire chief,who can then work with the owner
and local emergency services to develop an emergency response plan.
These measures can be combined with products to prevent theft of the panels. Some are very low cost
options (fastener type) while there are other options that are more expensive (alarm system type) but
also more effective. The biggest potential risk associated with solar PV systems is the risk of shock or
electrocution for firefighters and other emergency responders who could come in contact with high
voltage conductors. A 2010 study on firefighter safety and emergency response for solar PV systems by
the Fire Protection Research Foundation, based in Quincy, Massachusetts, recommended steps
firefighters can take when dealing with wiring and other components that may be energized. The Solar
Energy Business Association of New England (SEBANE) has been working to provide training and
education to first-responders to identify and avoid potential hazards when responding to a solar PV fire.
For more information about toxics/fires, see the Hazardous Materials Section.
Resources:
Moskowitz, P.D. and Fthenakis, V.M.,Toxic Materials Released from Photovoltaic Modules During Fires:
Health Risks, Solar Cells, 29, 63-71, 1990. 21.
Solar America Board for Codes and Standards
http://wwwsolarabcs.org/about/publications reorts/blinds_of/ dfs Blind$po pdf
__
Fire Fighter Safety and Emergency Response for Solar Power Systems: Final Report, May 2010. Prepared
by The Fire Protection Research Foundation
14
National Electric Code Article 250: Grounding and Bonding, Article 300: Wiring Methods,Article 690
Solar PV Systems, Article 705 Interconnected Electric Power Production Sources
15
Historic Preservation
The Question: What are the appropriate standards when land with historical or archaeological
significance is developed for large-scale solar PV arrays?
Bottom Line: Parties undertaking solar PV projects with state or federal agency involvement must
provide the Massachusetts Historical Commission (MHC)with complete project information as early as
possible in the planning stage, by mail to the MHC's office (see Resources). Parties should also contact
local planning, historical or historic district commissions to learn about any required local approvals.
Municipalities should also take the presence of historic resources into account when establishing zoning
regulations for solar energy facilities in order to avoid or minimize impacts.
More Information: Land being evaluated for the siting of large-scale solar PV has historical or
archaeological significance including properties listed in the National or State Registers of Historic Places
and/or the Inventory of Historic and Archaeological Assets of the Commonwealth.
Federal and state laws require that any new construction, demolition or rehabilitation projects
(including new construction of solar PV)that propose to use funding, licenses or permits from federal or
state government agencies must be reviewed by the MHC so that feasible alternatives are developed
and implemented to avoid or mitigate any adverse effects to historic and archaeological properties.
Projects receiving federal funding, licenses or permits are reviewed by the involved federal agency in
consultation with the MHC and other parties in compliance with Section 106 of the National Historic
Preservation Act of 1966 (16 U.S.C. 470f) and the implementing regulations(36 CFR 800) in order to
reach agreement to resolve any adverse effects. Projects receiving state funding, licenses or permits
must notify the MHC in compliance with M.G.L.c. 9, ss. 26-27C and the implementing regulations 950
CMR 71. If the MHC determines that the project will have an adverse effect,the involved state agency,
the project proponent,the local historical preservation agencies, and other interested parties consult to
reach an agreement that outlines measures to be implemented to avoid, minimize, or mitigate adverse
effects. For projects with both federal and state agency involvement,the Section 106 process is used..
Some communities have local preservation ordinances or established local historic districts that require
local approval for new construction visible from a public way. Local historic district commissions have
adopted design guidelines for new construction within their historic districts and historic
neighborhoods. However,these guidelines must account for Chapter 40C Section 7 of the General Laws,
which requires a historic district commission to consider the policy of the Commonwealth to encourage
the use of solar energy systems and to protect solar access.
Resources:
Federal Agency Assisted Projects:
Section 106 review information and the federal regulations 36 CFR 800 are available at the Advisory
Council on Historic Preservation (ACNP)web site:www.achp.gov. Check with the involved federal
agency for how they propose to initiate the MHC notification required by 36 CFR 800.3.
State Agency Assisted Projects:
16
Massachusetts General Laws Chapter 9, sections 26-27C
MHC Regulations 950 CMR 71 (available from the State House Bookstore)
MHC Review & Compliance FAQs http://www.sec.state.ma.us/mhc/mhcrevcom/revcomidx.htm
MHC Project Notification Form (PNF)&Guidance for Completing the PNF and required attachments
(USGS locus map, project plans, current photographs keyed to the plan). Mail or deliver the complete
project information to the MHC's office: http://www.sec.state.ma.us/mhc/mhcform/formidx.htm
General Guidance about Designing Solar PV Projects on Historic Buildings and in Historic Areas:
http://www.nrel.gov/docs/filllosti/51297.pdf
17
Noise
Question: Do the inverters,transformers or other equipment used as part of ground-mounted solar PV
create noise that will impact the surrounding neighborhood?
Bottom Line: Ground-mounted solar PV array inverters and transformers make a humming noise during
daytime, when the array generates electricity. At 50 to 150 feet from the boundary of the arrays, any
sound from the inverters is inaudible. Parties that are planning and designing ground-mounted solar PV
should explore options to minimize noise impacts to surrounding areas. This could include conducting
pre-construction sound studies, evaluating where to place transformers, and undertaking appropriate
noise mitigation measures.
More Information: Most typically,the source of noise associated with ground-mounted solar PV comes
from inverters and transformers.There also may be some minimal noise from switching gear associated
with power substations. The crackling or hissing sound caused by high-voltage transmission lines (the
"Corona Effect") is not a concern in the case of solar PV,which uses lower voltage lines.
Parties siting ground-mounted solar PV projects should consult equipment manufacturers to obtain
information about sound that can be expected from electrical equipment, since this can vary. For
example, according to manufacturer's information, a SatCon Powergate Plus 1 MW Commercial Solar PV
Inverter has an unshielded noise rating of 65 decibels(dBA) at five feet. This is approximately the sound
equivalent of having a normal conversation with someone three feet away. Another source of
information is the National Electrical Manufacturers Association (NEMA) standards, which will provide
maximum sound levels from various equipment arrays. From NEMA,a large dry-type transformer
(2001-3333 kVA) that is forced air cooled and ventilated has an average sound level of 71 dBA, which is
approximately the sound level one would expect from a vacuum cleaner at ten feet.There may be
several such units on a substantially sized PV site,which would increase the sound level to some degree.
Sound impacts from electrical equipment can be modeled to the property line or nearest sensitive
receptor(residence). Sound impacts can be mitigated with the use of enclosures, shielding and careful
placement of the sound-generating equipment on-site.The rule of thumb for siting noise-generating
equipment is that the sound impact can be reduced by half by doubling the distance to the receptor.
In some areas both in the US and Canada, sound impact analysis is required as part of the permitting
process for large PV systems. For example, in the Province of Ontario, Canada, any project greater than
12 MW is required to perform a sound impact analysis(Ontario 359/09). California also requires a sound
impact analysis for large PV projects. Massachusetts currently has no such requirement, but the reader
should note that ground-mounted systems in Massachusetts very rarely go over 6 MW, which is half the
size of the 12 MW that triggers a sound analysis in Ontario.
A recent study measured noise levels at set distances from the inverters and from the outer boundary of
three ground-mounted PV arrays in Massachusetts with a capacity range of 1 to 3.5 MW. Close to the
inverters (10 feet), sound levels varied from an average of 55 dBA to 65 dBA. Sound levels along the
fenced boundary of the PV arrays were generally at background levels,though a faint inverter hum
could be heard at some locations. Any sound from the PV array and equipment was inaudible and
18
sound levels were at background levels at setback distances of 50 to 150 feet from the boundary.
Project developers should consult with local planning and zoning officials to determine if local noise
ordinances may be applicable. Many local noise ordinances establish absolute limits on project impact
noise (such as a 40 dBA nighttime limit). In these communities, a noise impact assessment may be
required.
Resources:
NEMA Standards Publication No.TR=1-1993(R2000), Transformers, Regulators and Reactors
Noise Assessment: Borrego 1 Solar Project, MUP 3300-10-26 Prepared by Ldn Consulting, Inc, Fallbrook,
CA.January 14, 2011
Ontario Regulation 359/09 Renewable Energy Approval (REA) Regulation, Ontario Ministry of the
Environment, Canada http•//www.ontario.ca/environment-and-energy/renewable-energy-approvals
Tech Environmental,Study of Acoustic and EMF levels from Solar Photovoltaic Projects, Prepared for the
Massachusetts Clean Energy Center, December 2012,
http•//imagesmassceccom/uploads/attachments/Create%20Basic%20page/Study of Acoustic and E
MF Levels from Solar Photovoltaic Pro
19
Water-Related Impacts
Question: Can chemicals that might be contained in solar PV threaten public drinking water systems?
Will flooding occur in cases where trees must be removed in order to install the solar arrays? How do we
ensure that wetland resources are protected?
Bottom Line: Rules are in place to ensure that ground-mounted solar arrays are installed in a ways that
protect public water supplies,wetlands, and other water resource areas. All solar panels are contained
in a solid matrix, are insoluble and are enclosed. Therefore, releases are not a concern.
More Information: Because trees offer multiple water management, cooling and climate benefits,
clear-cutting of trees for the installation of ground-mounted solar PV is discouraged. For projects that do
propose to alter trees,the Massachusetts Environmental Policy Act (MEPA) has thresholds for the
proposed alteration of a certain number of acres of land,the size of electrical facilities, and other criteria
that trigger state review of proposed projects. Clear cutting of trees and other aspects of proposed
projects would be reviewed through an Environmental Notification Form/Environmental Impact
Statement if thresholds are triggered. More information is available at:
MassDEP has determined that the installation of solar arrays can be compatible with the operation and
protection of public drinking water systems.This includes the installation of solar arrays within the Zone
I, which is a 400-foot protective radius around a public ground water well. Solar projects proposed on
lands owned by public water systems outside the Zone I may be approved subject to standard best
management practices, such as the proper labeling,storage, use, and disposal of products. MassDEP has
a guidance/review process in place to ensure that the installation of ground-mounted solar PV in these
areas protects public water supplies.
Installing solar arrays on undeveloped land can preserve the permeable nature of the land surface
provided the project design minimizes disturbance to natural vegetative cover, avoids concentrated
runoff, and precipitation is otherwise recharged into the ground to the greatest extent practicable.
Storm water flow, as well as information about site-specific soils and slope, is taken into account during
the design and installation of solar arrays.
MassDEP discourages installation of ground-mounted solar PV systems in wetland areas, including
riverfront locations. Solar projects within wetland areas are unlikely to comply with the performance
standards in the Wetlands Protection Act regulations. If a solar installation is proposed in a wetland, a
riverfront area, a floodplain, or within 100 feet of certain wetlands, the project proponent must file a
notice of intent(or application to work in wetland areas)with the local Conservation Commission, which
administers the Wetlands Protection Act at the municipal level. Copies should also go to MassDEP. Solar
installations may be sited near, but outside of wetlands, in a manner that protects the functions of
wetlands and that minimizes impacts from associated activities such as access and maintenance.
Ancillary structures related to construction of a solar installation or transmission of power may be
permitted to cross rivers and streams using best design and management practices.
20
Resources:
More information about the Wetlands Protection Act requirements may be found in the implementing
regulations at 310 CMR 10.00: http://www.mass.gov/eea/agencies/massdep/water/regulations/310-
cm r-10-00-wetla nds-protection-act-regulations.htm I
MassDEP Guidance for Siting Wind and Solar in Public Water Supply Land:
http://www.mass.gov/eea/agencies/massdep/water/regulations/wind-and-solar-energy-project-on-
pubiic-water-supply-land.html
MassDEP Chapter 91 Guidance for Renewable Energy Projects:
http://www.mass.gov/eea/agencies/massdep/water/reports/chapter-91-I icensi ng-and-renewa ble-
energy.html
21
Glare
Question: How important is reflectivity and potential visual impacts from solar projects, especially near
airports?
Bottom Line: Solar panels are designed to reflect only about 2 percent of incoming light, so issues with
glare from PV panels are rare. Pre-construction modeling can ensure that the placement of solar panels
prevents glare.
More Information: Solar panels are designed to absorb solar energy and convert it into electricity. Most
are designed with anti-reflective glass front surfaces to capture and retain as much of the solar
spectrum as possible.Solar module glass has less reflectivity than water or window glass.Typical panels
are designed to reflect only about 2 percent of incoming sunlight. Reflected light from solar panels will
have a significantly lower intensity than glare from direct sunlight.
An analysis of a proposed 25-degree fixed-tilt flat-plate polycrystalline PV system located outside of Las
Vegas, Nevada showed that the potential for hazardous glare from flat-plate PV systems is similar to
that of smooth water and not expected to be a hazard to air navigation.
Many projects throughout the US and the world have been installed near airports with no impact on
flight operations. United Kingdom and U.S. aircraft accident databases contain no cases of accidents in
which glare caused by a solar energy facility was cited as a factor.
When siting solar PV arrays pre-construction modeling can ensure the panels are placed in a way that
minimizes any potential glare to surrounding areas.
Resources:
Technical Guidance for Evaluating Selected Solar Technologies on Airports, Federal Aviation
Administration, November 2010 (currently under review),
http://www.faa.gov/airports/"environmental/policy guidance/media/airport solar guide.pdf
A Study of the Hazardous Glare Potential to Aviators from Utility-Scale Flat-Plate Photovoltaic Systems,
Black&Veatch Corporation, August 2011, http•//www.isrn.com/journals/re/2011/651857/
Solar Photovoltaic Energy Facilities,Assessment of Potential Impact on Aviation,Spaven Consulting,
January 2011: http//www solarchoice net au/blog/solar-panels-near-airports-glare-issue/
22
Endangered Species and Natural Heritage
Question:Who ensures that rare animal and plant species and their habitats are not displaced or
destroyed during the construction of ground-mounted solar PV?
Bottom Line: Rules are in place to ensure that the installation of ground-mounted solar arrays protects
state-listed rare species and animals and plants. Project proponents can check with the local
Conservation Commission to determine if the footprint of the solar PV project lies within a rare species
habtat.
More Information: The Massachusetts Natural Heritage and Endangered Species Program (NEHSP)was
created under the Massachusetts Endangered Species Act (MESA) and is responsible for protecting rare
animal and plant species and their habitats from being displaced or destroyed. Specifically, NEHSP
reviews projects proposed for:
Priority Habitats: These are areas known to be populated by state-listed rare species of animals or
plants. Any project that could result in the alteration of more than two acres of Priority Habitat is
subject to NHESP regulatory review. Projects will need to file a MESA Information Request Form,
along with a project plan, a U.S. Geological Survey(USGS) topographical map of the site, and a $50
processing fee. NHESP will let project administrators know within 30 days if the filing is complete,
then will determine within the next 60 days whether the project, as proposed,would result in a
"take"of state-listed rare species that might require the project to redesign, scale down, or abandon
its plan.
Estimated Habitats: These are a sub-set of Priority Habitats that are based on the geographical
range of state-listed rare wildlife—particularly animals that live in and around wetlands. If the
project is proposed for one of these areas and the local Conservation Commission requires filing a
Notice of Intent(N01) under the Wetlands Protection Act,the project will need to submit copies of
the N01, project plans and a U.S. Geological Survey(USGS) topographical map to NHESP. Within 30
days of receiving this information, NHESP will send its comments to the Conservation Commission,
with copies to the project administrator, project consultants, and the Department of Environmental
Protection (MassDEP).
Resources:
To.learn more about the NHESP review process and download a MESA Information Request Form, visit:
http://www.mass.gov/eea/age ncies/dfg/dfw/natu ra I-heritage/regulatory-review/mass-enda nge red-
species-act-mesa/
For list of rare animal and plant species in Massachusetts, visit:
http://www.mass.gov/eea/agen cies/dfg/dfw/natural-heritage/species-information-a nd-
conservation/mesa-list/list-of-rare-species-in-massachusetts html
23
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Microwaves, Radio Waves, and Other Types of Radiofrequency
Radiation
What is radiofrequency (RF) radiation?
Radiation Is the emission(sending out)of energy from any SOUfGe.X-rays are an example of radiation,but SO IS the
light that comes from the sun and the heat that is constantly coming off our bodies.
When talking about radiation and cancer,many people think of specific kinds of radiation such as x-rays or the
radiation made by nuclear reactors. But there are other types of radiation that act differently.
Radiation exists across a spectrum from very high-energy(high-frequency)radiation to very low-energy(low-
frequency)radiation.This is sometimes referred to as the electromagnetic spectrum.
Examples of high-energy radiation include X-rays.a!jqqaimnei rays.They,as well as some higher energy UV
radiation,are called ionizing radiation,which means they have enough energy to remove an electron from(ionize)an
atom or molecule.This can damage the DNA Inside of calls,which can result in cancer.
Radiofrequency(RF)radiation is at the low-energy end of the electromagnetic spectrum and is a type of non-ionizing
htDIANww.carrAr.orolcancer/cancercauses/radlafloriexposureandcancer/radiofrequency-radlaflon 1/6
6/8/2015 Microwaves,Radio Waves,and Other Types of Radiofrequency Radiation
radiation.Non-lonizing radiation has enough energy to move atoms in a molecule around or cause them to vibrate,but
not enough to ionize(remove charged particles such as electrons).RF radiation has higher energy than extremely
low-frequency electromagnetic radiation,but lower energy than some other types of non-ionizing radiation,litre visible
light and infrared.Ionizing radiation has even higher energy.
If RF radiation is absorbed in large enough amounts by materials containing water,such as food,fluids, and body
tissues, it can produce heat.This can lead to burns and tissue damage,Although RF radiation does not cause cancer
by damaging DNA in cells the way Ionizing radiation does,there has been concern that some forms of non-Ionizing
radiation might have biological effects that could result in cancer in some circumstances.
How are people exposed to RF radiation?
People can be exposed to RF radiation from both natural and man-made sources.
Natural sources include:
• Outer space and the sun
• The sky—including lightning strikes
• The earth itself—most radiation from the earth is infrared,but a tiny fraction is RF
Man-made RF radiation is used for many different things,such as
• Broadcasting radio and television signals
• Transmitting signals from cordless telephones,cellular phones and cell phone towers, satellite phones,and 2-way
radios
• Radar
• WIFi and Bluetooth
• Cooking food(in a microwave oven)
• Heating body tissues to destroy them in medical procedures
• 'Welding"pieces of polyvinyl chloride(PVC)using certain machines
• Millimeter wave scanners(a type of full body scanner used for security screening)
Some people can have significant RF exposure as part of their jobs.This includes PVC welders,people who maintain
antenna towers that broadcast communication signals,and people who use or maintain radar equipment.
Most people are exposed to much lower levels of man-made RF radiation every day due to the presence of RF
signals all around us.They come from radio and television broadcasts,WFi and Bluetooth,cell phones (and cell
Rhone lowers),and other sources.
Microwave ovens
Microwave ovens work by using very high levels of a certain frequency of RF radiation(in the microwave spectrum)to
heat foods.When microwaves are absorbed by food containing water, it causes the water molecules to vibrate.This
produces heat.Microwaves do not use x-rays or gamma rays,and they do not Inake food radioactive. Microwave
ovens can cook food,but do not otherwise change the chemical or molecular structure of it.
Microwave ovens are designed so that the microwaves are contained within the oven itself.The oven only makes
microwaves when the door Is shut and the oven is turned on.When microwave ovens are used according to
instructions,there is no evidence that they pose a health risk to people.In the US,the federal standards limit the
amount of radiation that can leak from a microwave oven to a level far below what would hann people.Ovens that are
damaged or modified,however,could allow microwaves to leak out,and so could pose a hazard to people nearby by
potentially causing bums.
Although same people have been Injured from microwave ovens,most often they have been burns from contact with
steam or hot food.
In the past,there was a concern that leakage from microwave ovens could interfere with pacemaker function.
WMfww.cancer.org/cancer/Cancercauses/radiationexposureandcancer/radiofrequency-radiaUon 2J6
6!812015 Power Lines,Electrical Devices,and Extremely Low Frequency Radiation
non-ionizing radiation. Non-ionizing radiation has enough energy to move atoms in a molecule around or cause them
to vibrate, but not enough to remove charged particles such as electrons(Ionize)and directly damage DNA.ELF
radiation has even lower energy than other types of non-ionizing radiation like radiofrequency radiation,visible light,
and Infrared.
Extremely low frequency radiation has very large wavelengths—one wave can be 5000 kilometers(over 3000 miles)
across.This means that people and other living things are in only a small fraction of a wavelength.
Electromagnetic radiation is actually made of 2 parts—the electric field and the magnetic field.
Electric fields come from unbalanced electric charges on conductors.The electric field acts on charged particles—
like electrons or protons. It can cause these particles to move leading to the flow of electric current.The strength of
an electric field is often expressed as volts per meter(V/m)or for stronger fields kilovolts per meter(kV/m),where
1000 volts is the saine as a kilovolt.
A magnetic field only exists if the charges are in motion,such as with the flow of electric current.Direct current that
is going in one direction and permanent magnets produce static(unchanging)magnetic.fields.This is not a form of
ELF radiation.Time-varying magnetic fields (including those in the extremely low frequency range)are produced by
alternating current.The strength of a magnetic field can be expressed in many different units,including tesla(T),
microtesla(pT)(there are a million IiT in a tesla),and gauss(G),where one G equals 100 pT.
Magnetic fields can produce electric fields, and electric fields can produce magnetic fields.
With most types of radiation,the electric and magnetic fields are coupled. Because they act as one,they are
considered together as an electromagnetic field(EMF). But with ELF radiation,the magnetic field and the electrical
field can exist(and act)Individually, and so they are often studied separately. In this document,the term"magnetic
field"is used to Indicate ELF radiation from a magnetic field,while"electrical field"is used to mean ELF radiation from
an electrical field.
The possible link between electromagnetic fields and cancer has been a subject of controversy for several decades.
It's not clear exactly how electromagnetic fields,a.form of low-energy,non-ionizing radiation,could increase cancer
risk. Plus,because we are all exposed to different amounts of these fields at different times,the issue has been
difficult to study.
How are people exposed to ELF radiation?
Generating,transmitting,distribuling, and using electricity all expose people to ELF radiation.Some sources include
power lines, household wiring, and anything using electricity.This can Include anything frau refrigerators and vacuum
cleaners to television sets and computer monitors(when they are on).Even electric blankets expose people to ELF
radiation.
How much electromagnetic radiation someone is exposed to depends on the strength of the field,the distance from
the source of the field,and the length of time the person is exposed.The highest exposure occurs when the person is
very close to a source putting out a strong field and stays there for a long period.
Does ELF radiation cause cancer?
Studies in the lab
Four large studies looked at the effects of ELF magnetic fields on cancer in rats and mice.These studies exposed
the animals to magnetic fields much stronger than what people are nonnally exposed to at home,with fields ranging
from 2 to 5000 microtesla(pT).3 of these studies found no Increase in the nsk of any type of cancer.In fact,some
types of cancer were actually lower In the animals exposed to the ELF radiation.One study did show an increase risl(
of tumors and cancer that start in the C-cells of the thyroid in male rats at certain exposures.This increase risk was
not seen In mice or female rats,and was not seen at the highest field strength.These inconsistencies,and the fact
that these findings were not seen in the other studies,make it hard to conclude that the increased risk of tumors was
really from the ELF radiation.
Other studies In mice and rats looked specifically for a link between leukemia and lymphoma and exposure to ELF
radiation,but no link was found.
Studies in people
2/6
6/8/2015 Microwaves,Radio Waves,and Other Types of Radiofrequency Radiation
Pacemakers are now designed to be shielded from outside electrical activity,so this is no longer a concern for most
people.If you are worried,though,you can ask your doctor if being around a microwave is safe for you.
Full-body security scanners
In some airports in the United States,the Transportation Security Administration(TSA)uses full body scanners to
screen passengers.The scanners currently used by the TSA use millimeter wave imaging.These scanners send out
a small amount of millimeter wave radiation(a type of RF radiation)toward the person in the scanner.The RF
radiation passes through clothing and bounces off the personsskin as well as any objects under the clothes.The
radiation is sensed by receivers that create images of the person. - -
Millimeter wave scanners do not use x-rays (or any other kind of high-energy radiation)and the amount of RF
radiation used Is very low—much less than that from a cell phone.According to the Food and Drug Administration,
these scanners have no known health effects. However,TSA allows people to be screened In a different way if they
object to screening with these scanners.
Cell phones and cell phone towers
Cell phones and cell phone towers use RF radiation to transmit and receive signals.Some concerns have been raised
that these signals might increase the risk of cancer, and research in this area continues.For more detailed
Information,refer to our documents Cellular Phones and Cellular Phone Towers.
Does RF radiation cause cancer?
Researchers use 2 main types of studies to try to determine if something might cause cancer.
Lab studies usually expose animals to chemical or physical agents(such as RF energy)to see if it causes tumors or
other health problems. It's not always clear if the results from these types of studieswill apply to humans,but lab
studies allow researchers to carefully control for other factors that might affect the results and to answer some basic
science questions.
Another type of study looks at cancer rates in different groups of people.Such a study might compare the cancer rate
in a group exposed to something like RF energy versus the rate in a group not exposed to it,or compare it to what the
expected cancer rate world be in the general population.But studies in people can sometimes be hard to interpret,
because there may be other factors affecting the results that are hard to account for.
In most cases neither type of study provides enough evidence on its own to show if something causes cancer in
people,so researchers usually look at both lab-based and human studies.
Studies done in the lab
Most animal and laboratory studies have found no evidence of an increased risk of cancer with exposure to RF
radiation.A few studies have reported evidence of biological effects that could be linked to cancer..
Studies in people
Studies of people who may have been exposed to RF radiation at thelrjobs(such as people who work around or with
radar equipment,those who service communication antennae,and radio operators)have found no clear Increase in
cancer risk.
A number of studies have looked at the possible link between cell phones and cancer.Although one large study
showed a possible link,most studies did not. Still,many question the quality of these studies and their ability to find
a link.The possible link between cell phones and cancer risk Is discussed in detail in our document Cellular Phones,
What do expert agencies say?
Several agencies(national and international)study different substances in the environment to determine if they can
cause cancer.(A substance that causes cancer or helps cancer grow Is called a carcinogen.)The American Cancer
Society looks to these organizations to evaluate the risks based on evidence from laboratory,animal,and human
research studies.
http'lANww.cancer.orgtcancer/canwcauses/radiationexposureandcancer/radlofrequeney-radiation Te
8/8/2015 Microwaves,Radio Waves,and Other Types of Radiofrequency Radiation
The International Agency for Research on Cancer(IARC)is part of the World Health Organization. Its major goal is to
identify causes of cancer.IARC has stated that there is thrilled evidence that RF radiation causes cancer In animals
and humans, and classifies RF radiation as"possibly carcinogenic to humans"This was based on the finding of a
possible link in at least one study between cell phone use and a specific type of brain tumor. IARC considers the
evidence overall to be"limited"because of the conflicting findings and generally low quality of the studies that have
been done.
The other main agencies that classify cancer-causing exposures(carcinogens),including the US Environmental
Protection Agency(EPA)and the National Toxicology Program(NTP), have not formally classified RF radiation as to
Its cancer-causing potential.
(For more information on the classification systems used by these agencies,see our document Known and Probable
Human Carcinogens.)
Does RF radiation cause any other health problems?
Studies in the lab
In animals,the main effects of exposure to RF are related to heating(sometimes called thermal effects).High doses
of RF radiation can raise body temperature,even to the point of being fatal. Focusing RF radiation on one area of the
body can lead to bums and the breakdown of tissue.When RF waves are focused on the eye,it can cause cataracts
to form.
It Isn't clear what effects,if any, RF radiation has at levels of exposure too low to produce heating.
In people
People have been exposed to large amounts of RF radiation through accidents involving radar equipment.This has
led to severe burns.
People who are near microwave radar equipment can be exposed to enough pulsed microwave radiation(a type of RF
radiation)that they begin to hear clicking noises.This is sometimes called RF hearing and does not seem to cause
long term health problems.
Although there is concern that people exposed to low levels of microwaves over long periods of time in their jobs
could have an increased risk of cataracts or loss of fertility(in men),this has not been seen in large studies,
Flow can I avoid exposure to RF radiation?
Because sources of RF radiation are so common in the modern environment,there is no way to completely avoid
exposure to it. It may be possible to lower your exposure to RF radiation by avoiding jobs with increased RF
exposure,keeping away from appliances and equipment that use RF,and using devices that allow mobile phones to
be used without placing them against the ear. Still, it isn't clear that doing so will be helpful in terms of health risks.
Additional resources
More information from your American Cancer Society
The following related information may also be helpful to you.These materials may be viewed on our website or
ordered from our toll-free number, at 1-800-227-2345.
Cellular Phones -
Cellular Phone Towers
Known and Probable Human Carcinogens
Ultraviolet(UV)Radiation
X-rays,Gamma Rays,and Cancer Risk
National organizations and websites
Mop:/Naww.cancer.org/cancer/cancercauses/radlatlonexposureandcancer/radiofrequency-radiation 416
6/8/2015 Power Lines,Electrical Devices,and Extremely Low Frequency Radiation
cathoderay tubes(CRT)use magnetic fields to create Images,and could expose people to higher levels of ELF
radiation than flat panel screens.but either type can give of ELF radiation.The amount of energy given off by both
CRT and flat screens is far below government exposure thresholds.At this time the available evidence does not
support links between ELF radiation from television and computer screens and health problems.Still,some screens
are designed to minimize the magnetic fields that they give off.These are labeled as being"TCO 99"or"TCO 03"
compliant.
Power lines
People Who are concerned about ELF radiation exposure from power lines should keep in mind that the intensity of
any exposure goes down drainatically as you get further away from the source.The strength of the field Is highest
directly under the power line.As you get further away,you are exposed to less and less,so that the level drops to
normal home background levels.Also, although being directly under a power line exposes you to its highest strength
field, It is often in the range of what you could be exposed to when using certain household appliances.
If you are concerned about living near power lines,you can measure the field strength with something called a
gaussmeter.Options for lowering exposures may be expensive and difficult to implement,such as moving to a new
home or having the power company bury the lines.But according to the NIEHS,it's not clear if such actions are
warranted because scientists aren't sure if EMF(such as ELF radiation)poses any health hazards,
Additional resources
More information from your American Cancer Society
The following related Information may also be helpful to you.These materials may be viewed on our web site or
ordered from our toll-free number,at 1-800-227-2345.
Known and Probable Human Carcinogens
Microwaves,Radio Waves,and Other Types of Radiofrequency Radiation
Radon
Smart Meters
Ultraviolet(UV)Radiation
X-rays, Gamma Rays.antl Cancer Risk
National organizations and Web sites*
In addition to the Amencan Cancer Society, other sources of information and support include:
Centers for Disease Control and Prevention(CDC)
Toll-free number: 1-800-232-4636(1-800-CDC-INFO)
Website:w.w+.cdc.gov
Environmental Protection Agency(EPA)
Website:www.epa.goy
Understanding Radiation:http_//www:epa,goy/radiation/understandtindex.htmI
National Cancer Institute(NCI)
Toll-free number: 1-800-422-6237(1-8004-CANCER)
Website:www.cancer.gov
Magnetic Field Exposure and Cancer:vrww.cancer.goy/cance,rtopics/factsheet/Risk/magnetic-fields
National Institute of Environmental Health Sciences
Website:www.niehs.nih.gov
Electric and Magnetic Fields:http://www.nieh.s.ifth,goWh,ealth/toples/agentste.m.f/index.cfm
*Inclusion on this list does not imply endorsement by the American Cancer Society.
No matter Who you are,we can help.Contact us anytime,day or night,for information and support:Call us at 1-800-
hlfp9Avww.cartcer.org/cancer/CwrmcausestradiaHonexpasureandcancer/extremely-low-frequency-radaUon 466
618/2015 Microwaves,Radio Waves,and Other Types of Radiofrequency Radiation
In addition to the American Cancer Society, other sources of information and support include:
Centers for Disease Control and Prevention(CDC)
Toll-free number: 1-800-232-4636(1-800-CDC-INFO)
Website:www.cdc-gov
Environmental Protection Agency(EPA)
Website:wvwd.epa.goy
Understanding Radiation:www epa gov/radiatioNunderstanding-radiation ovewlew.html
National Cancer Institute(NCI)
Toll-free number:1-800-422-6237(1-8004-CANCER)
Website:www.cancer.gov
Magnetic Field Exposure and Cancer:www.cancer.gov/cancedopics/fa ctsheet/Rlsk/magnetic fields
._ ... ...-. _ ... . .... ...........
National Institute of Environmental Health Sciences
Website:www.niehs.nih.gov
Electric and Magnetic Fields:wr niehs.nih.gov/healtWtopics/agents/emf/index.cfmww
°Inctusion on this list does not imply endorsement by the Amedcan Cancer Society.
No matter who you are,we can help.Contact us anytime,day or night,for information and support.Callus at 1-800-
227-2345 or visit www.cancer.org.
References
Alexander RC, Surrell JA,Coble SD. Microwave oven hums to children: an unusual manifestation of child abuse.
Pediatrics. 1987;79(2):255-260.
Castillo M,Quencer RM.Sublethal exposure to microwave radar.JAMA. 1988;259(3):355.
Elder JA,Chou CK.Auditory response to pulsed radiofrequency energy. B/oelectromagnetics.2003;Suppl 6:5162-73.
Elder JA.Ocular effects of radiofrequency,energy.Bioelectromagnetics.2003;Suppl 6:S148-61.
Federal Communications Commission. Radio Frequency Safely FAQs.6/25/2012.Accessed at
http://transition.fee.gov/oetMsafetybi-faqs.html on September 13,2013.
Food and Drug Administration.Radiation-Emitting Products and Procedures: Products for Security Screening of
People.6/8/2012.Accessed at http://www.fda.gov/Radiation-
EmittingProducts/RadiationEmittingProductsandProcedures/Secunty5ystems/ucm227201.htm on September 13,
2013.
Food and Drug Administration.Microwave Oven Radiation. 1/13/2010.Accessed at http://www.fda.gov/Radlatlon-
EmiltingProducts/RadialionEmittingProductsandProcedures/HomeBusinessandEntedainnlent/ucml42616.htm on
August 29,2013.
International Agency for Research on Cancer, IARC Monographs on the Evaluation of Carcinogenic Risks to Humans.
Volume 102,pad 2:Non-Ionizing Radiation, Radiofrequency Electromagnetic Fields.
Leonard A, Bedeaud AJ,Bruyere A.An evaluation of the mutagenic,carcinogenic and teratogenic potential of
microwaves.Mutat Res. 1983;123(1):31-06.
Oktay MF, Dasdag 5,Akdeie M,Cureoglu S,Cebe M,Yazicioglu M,Topeu I,Mere F.Occupational safety:effects
of workplace radiofrequencies on heading function.Arch Med Res.2004 Nov-Dec;35(6):517-21.
Petersen RC. Bioeffects of microwaves:a review of current knowledge,J Occup Med. 1983;25(2):103-110.
Transportation Security Administration.Advanced Imaging.Technology Traveler's Guide,7/23/2013.Accessed at
www.tsa.gov/traveler-informallonladvaiiced-imaging-technology-alt on September 13,2013.
World Health Organization.Electromagnetic gelds&public health:Microwave ovens. February 2005.Accessed at
www.who.Int/peh-einf/publications/facts/info_microwaves/en/on August 29,2013.
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6/8/2015 Microwaves,Radio Waves,and Other Types of Radiofrequency Radiation
Last Medical Review: 1011612013
Last Revised: 10/16/2013
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identified to date is a possible increased (CGS),gallium arsenide(GaAs),and cadmium
incidence of childhood leukemia. The main telluride (CdTe). Silica mining is associated
burden of disease following nuclear accidents with risk of silicosis, a type of pneumoconiosis
has been thyroid cancer and mental health (123). PV manufacturing, like semiconductor
impacts in exposed populations,with additional manufacturing, may entail exposure to toxic
impacts on cleanup workers.Further concerns metals (cadmium, arsenic, chromium, and
include the local effects of uranium mining and lead) and gases (arsine, phosphine, and silane)
milling and the management of nuclear waste. (59, 210). Little information is available on
The potential for weaponization or terrorist workplace exposures; available data suggest
attacks on nuclear fuel cycle facilities,however, that environmental emissions are generally low
pose the most difficult,yet perhaps the largest, (59), although waste management and end-of-
risks to quantify and manage(220). life product disposal remain challenges (191).
en Overall the health impact of solar power is likely
oto be far less than that of any of the fossil fuels.
y
EMERGING/RENEWABLE
� Renewable sources of energy offer several Biofuels
hey do
q o deplete
potential
finite rresources, and notirreversibly
havevla Biofuels are derived from recently formed
a lower climate footprint than do fossil fuels. biomass(as opposed to the ancient biomass that
o If managed well, they can pose minimal comprises fossil fuels). Ethanol and biodiesel,
health risks and can yield social and economic the two principal modern biofuels, are
0 o cobenefits. Whether the benefits are realized primarily liquid transportation fuels. First-
depends strongly on how renewable energy is generation biofuels such as ethanol are made
roduced. No ener source is free of health from food crops; including grain, sugar beets,
q P gY
and environmental impacts. Issues of land use, and sugarcane, and blended with petroleum-
o,o maintenance, materials inputs, and energy based gasoline. Biodiesel is made from
.saC storage raise concerns about environmental, vegetable or animal fats; it is used either in
M
occupational,and community health impacts. pure form or as a blend with conventional diesel
Nca fuel.Second-generation biofuels,which are un-
der development,will draw on a broader range
0 w Solar of plant and nonfood sources, such as crop
Three technologies are used to generate elec- residues, switch grass, and algae, and will use
atricity from solar radiation: photovoltaic (PV) advanced production processes. The aims are
cells, which generate electricity directly; con- to spare the use of food crops—lowering global
d
centrating solar power thermal systems,which food prices and promoting nutrition—spare
6 use a liquid to transfer absorbed heat to asteam productive.farmland,reduce fossil fuel and wa-
generator that drives a turbine; and solar tow- ter use, and protect water quality and wildlife
ers,which are effectively chimneys in which ris- habitat. Global biofitel production grew from
ing hot air powers turbine generators.Solar en- 16 billion liters in 2000 to more than 100 bil-
ergy technologies have been deployed in both lion liters in 2011, supplying—I.5% of global
small-scale(mainly rooftop)applications and in transportation fuel. Some countries rely heav-
large-scale electrical production. ily on biofuels. For example, 23% of Brazil's
The major health concern from solar power transportation fuel is biofuel;the United States
relates to the life cycle of PV cells. These are has reached 10% ethanol in light-duty vehicles
typically made with crystalline silicon and, (214) and may achieve 15-17% by 2030 (43).
depending on the technology used, include Subsidies and other policy incentives have
compounds such as copper indium diselenide supported the growth of the biofuel industry.
(CIS), copper indium gallium diselenide However, the drought-associated fall in the
wwro.nnnvalreaiewr.org • EneiV and Hnmmv Health r7r
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Health and Safety Concerns of Photovoltaic Solar Panels
Introduction
The generation of electricity from photovoltaic(PV) solar panels is safe and effective. Because PV
systems do not burn fossil fuels they do not produce the toxic air or greenhouse gas emissions
associated with conventional fossil fuel fired generation technologies.According to the U.S. Department
of Enerlgy, few power-generating technologies have as little environmental impact as photovoltaic solar
panels.
However, as with all energy sources, there are potential environmental, health and safety hazards
associated with the full product life cycle of photovoltaics. Recent news accounts have raised public
interest and concerns about those potential hazards?A substantial body of research has investigated the
life cycle impacts of photovoltaics including raw material production, manufacture, use and disposal.
While some potentially hazardous materials are utilized in the life cycle of photovoltaic systems, none
present a risk different or greater than the risks found routinely in modern society.
The most significant environmental, health and safety hazards are associated with the use of hazardous
chemicals in the manufacturing phase of the solar cell. Improper disposal of solar panels at the end of
their useful life also presents an environmental, health and safety concern. The extraction of raw material
inputs, especially the mining of crystalline silica, can also pose an environmental, health and safety
The environmental, health and safety concerns for the life-cycle phase are minimal and limited to rare and
infrequent events. With effective regulation, enforcement, and vigilance by manufacturers and operators,
any danger to workers, the public and the environment can be minimized. Further, the benefits of
photovoltaics tend to far outweigh risks especially when compared to conventional fossil fuel
technologies.According to researchers at the Brookhaven National Laboratory, regardless of the specific
technology, photovoltaics generate significantly fewer harmful air emissions (at least 89%) per kilowatt-
hour (KWh) than conventional fossil fuel fired technologies.3
Materials used in photovoltaics solar panels
The basic building block of a photovoltaic solar system /
is the solar cell. Solar cells are solid state,
semiconductor devices that convert sunlight into
electricity.Typically a number of individual cells are
connected together to form modules, or solar panels. In Cover film
order to provide electrical insulation and protect against
environmental corrosion,the solar cells are encased in solar cell
a transparent material referred to as an encapsulant. �— Encapsulant
To provide structural integrity the solar cells are Substrate
mounted on top of a rigid flat surface or substrate. A
it transparent cover film, commonly glass, further protects - — Cover film
-seal
these components from the elements. Gasket
Several types of semiconductor materials are used to
Frame
manufacture solar cells but the most common material Courtesy of the U.S. Department of Energy
is crystalline silicon, typically from quartz or sand,
capturing a 60% market share 4 Crystalline silicon
semiconductors are also utilized in the manufacture of integrated circuits and microchips used in personal
computers, cellular telephones and other modern electronics.
The outer glass cover constitutes the largest share of the total mass of a finished crystalline photovoltaic
module (approximately 65%),followed by the aluminum frame (-20%), the ethylene vinyl acetate
encapsulant(-•7.5%),the polyvinyl fluoride substrate (-2.5%), and the junction box (1%). The solar cells
themselves only represent about four percent(4%) of the mass of a finished module.6
makingsustainabilitywoY 65 Centennial Loop,Suite 3,Eugene,OR 97401 p:541.341.4663 (:541.341.6412 www.goodcompany.com
Oregon Department of Transportation Solar Highway photovoltaic solar panel selection
The solar panels proposed for use in the Oregon Department of Transportation's Solar Highway program
feature domestically manufactured and assembled monocrystalline silicon modules. The information
presented below, therefore, focuses on the life cycle environmental, health and safety hazards generally
associated with this technology.
Life Cycle of Monocrystalline Silicon Solar Panels
The simplified process diagram below illustrates the basic life-cycle stages for the manufacturing of
monocrystalline silicon (c-Si) solar panels.
The life cycle of a c-Si panel starts with mining of crystalline silica in the form of quartz or sand. The raw
material is then refined in industrial furnaces to remove impurities to produce metallurgical grade silicon
(-98% pure silicon). The metallurgical grade silicon is then further refined to produce high purity
polysilicon for use in the solar and semiconductor industry. Next, the polysilicon is used to grow
monocrystalline rods or ingots. These ingots are then shaped and sawn into very thin wafers. The wafers
are then manufactured into solar cells and assembled into photovoltaic modules ready for installation. At
the end of their useful life the materials in the panels can recycled and used as feedstock material for new
panels.
The potential environmental, health and safety hazards associated with each of these steps are described
on the following pages.
Figure 1: Simplified Photovoltaic Solar Panel Life Cycle
Raw material
extraction &
refining
End-of-life Module
management & manufacturing
recycling & assembly
Installation &
use
Jl �plp K
Raw material extraction and refining for solar panels
The material inputs phase consists of the extraction and processing of raw materials that are then used in
the production of solar panels.
Crystalline Silica Mining
Process
Crystalline silica is the primary raw material input for the manufacture of monocrystalline solar panels.
Crystalline silica is found in the environment primarily as sand or quartz. The extraction process varies by
location, but typically involves some combination of earth moving, crushing, milling, washing, and
screening to separate the crystalline silica particles from other minerals and impurities and to achieve the
desired grain sizes The end product is variously referred to as silica sand, quartz silica or simply silica or
quartz.
Health and Safety
A potentially harmful by-product associated with the mining and processing of silica sand is crystalline
silica dust. Silica dust has been associated with silicosis, a lung disease where scar tissue forms in the
lungs and reduces the ability to breath.' Crystalline silica dust is classified as a known human carcinogen
by the International Agency for Research on Cancer.' Studies show increased risk of developing lung
cancer through regular exposure to crystalline silica dust. Other health problems associated with regular,
high exposure include chronic obstructive pulmonary disease, rheumatoid arthritis,scleroderma,
Sjogern's syndrome, lupus, and renal disease.9
The widely recognized risk of human exposure to silica dust has resulted in the implementation of
stringent health, safety, and environmental measures in the United States and across the globe.
Examples of mitigation measures include monitoring air quality, automation of processes to limit human
exposure, dust suppression measures and personal protective devices forworkers such as respirators.10
It should be noted that the majority of global silica sand production (more than 80%) is used for the
manufacture of glass and ceramics, metal casting and abrasives, while only 2% is utilized in the
production of metallurgical grade silicon.tl
Upgrading Silica Sand to Metallurgical Grade Silicon
Process
Metallurgical grade silicon is used in the manufacture of metal alloys such as aluminum and steel,
chemical silicones for use in lubricants and epoxies as well as high purity polysilicon for the manufacture
of semiconductors including solar panels. Consumption by the semiconductor industry, including
photovoltaics, accounts for approximately 6% of global metallurgical grade silicon production.12 In order
to transform industrial grade silica sand into metallurgical grade silicon, the silica is combined with carbon
in the form of charcoal, coal, or coke in an electric arc furnace in a process called carbothermic reduction.
Health and Safety
The primary emissions from this process are carbon dioxide and sulfur dioxide from the combustion of
carbon sources. Another by-product of the process is fume silica captured via a piece of emission control
technology called a bag house. If respirated,fume silica can pose the same health concerns as silica
dust.13 Additionally, there are indirect emissions of carbon dioxide from the consumption of electricity to
power the electric arc furnace. The source and carbon intensity of this electricity varies by region.
Upgrading Metallurgical Grade Silicon to Polysilicon
Process
In order to reach a purity level acceptable for use in manufacture of semiconductor devices, metallurgical
grade silicon must go through two additional purification steps. The primary output from this purification
process is polysilicon, the precursor to the silicon wafers used to manufacture the integrated circuits at
the heart of most electronics as well as monocrystalline photovoltaic solar cells.
! 1 1 M
In the first step, pulverized metallurgical grade silicon is combined with hydrogen chloride gas and a
copper catalyst in a fluid bed reactor to produce trichlorosilane. Trichlorosilane is the primary chemical
feedstock for the production of polysilicon.This step also yields silicon tetrachloride,which can either be
captured and further processed into trichlorosilane or utilized as a feedstock in the manufacture of fiber
optics. Other byproducts from this phase include silane, dichlorosilane and chlorinated metals.
Dichlorosilane is an important precursor to silicon nitride, a ceramic material used, among other
applications, in the manufacture of automobile engine parts.14,15
To produce polysilicon, the trichlorosilane is subjected to a distillation process until the desired purity level
is achieved. The purified trichlorosilane is then used to deposit very pure polysilicon in a chemical vapor
deposition reactor. This process, commonly referred to as the Siemens process, accounts for as much
as 98% of the world's polysilicon production.16 Historically, polysilicon destined for photovoltaic solar cells
was considered "waste" material that did not meet the puritly requirement of the electronics industry and
accounted for approximately 10% of polysilicon production. 7 There are indications that this trend may be
changing as the size of photovoltaic markets expand.
Health and Safety
This process involves multiple potentially hazardous materials and byproducts that without proper
safeguards can pose a significant risk to human and environmental health. Chlorosilanes and hydrogen
chloride are toxic and highly volatile, reacting explosively with water. Chlorosilanes and silane can also
spontaneously ignite and under some conditions explode.18 Silicon tetrachloride can cause skin burns
and is also an eye and respiratory irritant.19 Silicon tetrachloride has recently gained notoriety due to
news accounts of its dumping near a polysilicon plant in China?6
Notably, Western production facilities accounted for more 99% of global polysilicon production in 2005,
the latest year for which data is available.2' These facilities use a closed loop process that captures
system byproducts for recycling and reuse within the process loop because these recovery systems are
necessary for the economic operation of a facility.22 Furthermore, any waste gasses not recoverable for
recycling are led through a series of pollution control technologies (e.g.wet scrubbers) prior to any
environmental releases. Environmental releases include very low levels of particulate matter, hydrogen
chloride and silicon tetrachloride.23
Furthermore, facilities in the United States, Japan and Europe are subject to strict environmental and
occupational health and safety regulation and enforcement. In contrast, production capacity is rapidly
expanding in developing countries such as China and India where such safeguards may not exist or be
enforced. Regardless of their location, reputable and responsible firms will have implemented beyond
compliance environmental management systems (e.g. ISO 14001 certification) and adopted voluntary
industry best management guidelines (e.g. Responsible Care).
Manufacturing and assembly of solar panels
From Wafer to Cell
Process
Solar cells are produced by transforming polysilicon into a cylindrical ingot of monocrystalline silicon,
which is then shaped and sliced into very thin wafers. Next, a textured pattern is imparted to the surface
of the wafer in order to optimize the absorption of light. The wafer is then subjected to high temperatures
in the presence of phosphorous oxychloride in order to create the physical properties required to produce
electricity. Next an anti-reflective coating of silicon nitride is applied to the top surface of the cell to
minimize reflection and increase efficiency of light absorption. Finally, metallic electrical conductors are
screen printed onto the surface wafer to facilitate the transport of electricity away from the cell.The
production of solar cells is concentrated in Japan, Europe and the United States, which currently account
for more than 80% of global production,24
Health and Safety
Many different potentially hazardous chemicals are used during the production of solar cells. The primary
environmental, health and safety concerns are exposure to and inhalation of kerf dust, a byproduct of
�tahi
sawing the silicon ingots into wafers, and exposure to solvents, such as nitric acid, sodium hydroxide and
hydrofluoric acid, used in wafer etching and cleaning as well as reactor cleaning. Many of these solvents
also pose a risk of chemical burns. Other occupational hazards include the flammability of silane used in
the deposition of anti-reflective coatings.25
The most likely exposure route for factory workers is inhalation of vapors or dusts. Secondarily, there is
exposure risk for factory workers from accidental spills. Risks to surrounding communities include the
release of hazardous gasses from an industrial accident or fire at the manufacturing facility. These
hazards are regulated by a number of occupational and environmental standards as well as industry
adopted voluntary best management practices. These regulations and strategies include: extensive
occupational ventilation systems, accident prevention and planning programs and emergency
confinement and absorption units?' As a result of these safeguards, there have been no known
catastrophic releases of toxic gases from photovoltaic manufacturing facilities in the United States 28
Module components and assembly
Process
A typical solar module consists of several individual cells wired together and enclosed in protective
material called an encapsulant, commonly made of ethylene vinyl acetate. To provide structural integrity
the encapsulated cells are mounted on a substrate frequently made of polyvinyl fluoride. Both ethylene
vinyl acetate and polyvinyl fluoride are widely considered to be environmentally preferable to other
chlorinated plastic resins. A transparent cover, commonly glass, further protects these components from
weather when In place for electrical generation. The entire module is held together in an aluminum
frame. Most modules also feature an on board electrical junction box 29
Health and Safety
Individual solar cells are typically soldered together with copper wire coated with tin. Some solar panel
manufacturers utilize solders that contain lead and other metals that if released into the environment can
pose environmental and human health risks. Module assembly is not a likely pathway for human
exposure to these metals as this step in the assembly process is typically automated. For more
discussion regarding the end-of-life product phase risks of lead containing solders, see the discussion in
the decommissioning and recycling section below.
Installation and use of solar panels
Installed silicon-based cells pose minimal risks to human health or the environment according to reviews
conducted by the Brookhaven National Lab and the Electric Power Research Institute.so
Health and Safety
Because solar panels are encased in heavy-duty glass or plastic, there is little risk that the small amounts
of semiconductor material present can be released into the environment.
In the event of a fire, it is theoretically possible for hazardous fumes to be released and inhalation of
these fumes could pose a risk to human health." However, researchers do not generally believe these
risks to be substantial given the short-duration of fires and the relatively high melting point of the materials
present in the solar modules. 32 Moreover, the risk of fire at ground-mounted solar installations is remote
because of the precautions taken during site preparation including the removal of fuels and the lack of
burnable materials—mostly glass and aluminum—contained in a solar panel.
A greater potential risk associated with photovoltaic systems and fire is the potential for shock or
electrocution if a fire-fighter or emergency responder comes in contact with a high voltage conductor.
These concerns are almost entirely related to roof mounted residential and commercial solar arrays. The
Oregon Building Code Division is currently considering new rules to increase public safety for structures
equipped with solar photovoltaic systems. The proposed rules are inspired by a model code adopted by
the California Department of Forestry & Fire Protection. As it applies to ground mounted photovoltaic
arrays,the California model code calls for a clear marking of system components in order to provide
emergency responders with appropriate warnings 33
The strength of electromagnetic fields produced by photovoltaic systems do not approach levels
considered harmful to human health established by the International Commission on Non-Ionizing
Radiation Protection. Moreover the small electromagnetic fields produced by photovoltaic systems
rapidly diminish with distance and would be indistinguishable from normal background levels within
several yards. For a detailed discussion of electromagnetic fields and solar arrays read the Scaling Public
Concerns of Electromagnetic Fields Produced by Solar Photovoltaic Arrays paper at
http://www.oregonsolarhighway.com.
End-of-life management and recycling of solar panels
Process
While the solar cell is the heart of a photovoltaic system, on a mass basis it accounts for only a small
fraction of the total materials required to produce a solar panel. The outer glass cover constitutes the
largest share of the total mass of a finished crystalline photovoltaic module (approximately 65%),followed
by the aluminum frame (-20%), the ethylene vinyl acetate encapsulant (-7.5%), the polyvinyl fluoride
substrate (-2.5%), and the junction box(1%). The solar cells themselves only represent about four
percent(4%) of the mass of a finished module.34
Proper decommissioning and recycling of solar panels both ensures that potentially harmful materials are
not released into the environment and reduces the need for virgin raw materials. In recognition of these
facts,the photovoltaic industry is acting voluntarily to implement product take-back and recycling
programs at the manufacturing level, Collectively, the industry recently, launched PV Cycle—a trade
association to develop an industry-wide take back program in Europe. 5 In the United States, product
take-back and recycling programs vary by manufacturer; SolarWorld,the supplier selected for the three
Oregon Solar Highway projects, is one of the manufacturers which fully supports the entire life cycle of
their product.
While recycling methods and take-back policies vary by manufacturer, the most frequently recycled
components are the cover glass, aluminum frame, and solar cells. Small quantities of valuable metals
including copper and steel are also recoverable. The ethylene vinyl acetate encapsulant and polyvinyl
Fluoride substrate are typically not recoverable and are removed through a thermal process with strict
emission controls and the by-product ash land-filled. Following this process, the glass and aluminum
frame are separated and typically sold to industrial recyclers. The solar cells are then reprocessed into
silicon wafers with valuable metals recovered and sold. Depending on the condition, the wafer can then
either be remade into a functioning cell or granulated to serve as feedstock for new polysilicon.36
Health and Safety
If not properly decommissioned, the greatest end of life health risk from crystalline solar modules arises
from lead containing solders. Under the right conditions it is possible for the lead to leach into landfill
soils and eventually into water bodies. Notably total lead solder use accounts for only approximately
0.5% of lead use in the United States.
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Characterization." Chiang Mai Journal of Science.Vol. 34, No.1:47-53.Available at
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Applications in IT and Renewable Energy."Tokyo: United Nations University Institute of Advanced Studies.Available
at htlp//www.it-environment.org/i)ublications/QITS reportpdf
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Characterization" Chiang Mai Journal of Science.Vol. 34, No.1: 47-53.Available at
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Characterization." Chiang Mai Journal of Science.Vol.34, No.1:47-53.Available at
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at hftp�//mvdocs,epri.com/docs/public/000000000001 000095.pd .
33 California Department of Forestry and Fire Prevention (2008).Solar Photovoltiac Installation Guidelines.
Sacramento: CA.Available at: http l/osfm fire ca qov/pdf/reports/solarphotovottaicguideline pdf
34 Knut Sander(2007). Study on the Development of a Take Back and Recovery System for Photovoltaic Products.
Brussels: Belgium: PV Cycles.Available at:
htti)//www pvcvcle org/fiieadmin/pvcycle docs/documents/publications/Report PVCycle Download En.pdf
as SolarWorld AG(2008). "Annual Group Report 2008—With Integrated Sustainability Report SolarWorld AG."
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36 Knut Sander(2007). Study on the Development of a Take Back and Recovery System for Photovoltaic Products.
Brussels: Belgium: PV Cycles,Available at:
hltp•//www pvcvcle ora/fileadmin/ovcvcle docs/documents/publications/Report PVCvcle Download En 3df
6/5/2015 SE Iowa school district to became first powered almost entirely by solar I Iowa Environmental Focus
Iowa Environmental Focus
Environmental news, research and analysis
SE Iowa school district to become first powered
almost entirely by solar
r
I
(httl2s•//iowaenvironmentalfocus files wordpress com/2015/06/solar-power pf�g)
Principal Jeff Nance stands by one of four sets of solar panels at WACO High School in
Wayland. This set operates lights for the school's football field. (John Gaines/The Hawk
Eye (http://thehawkeye.com/story/WACO-goes-Solar-11614))
hltpJfimaenvironmentalfocus.orgt20l5/06/05/se-iowa-school-district-to-become-first-powered-almost-entirely-by-solar/ 1/3
515/2015 SE Iowa school district to become first powered almost entirely by solar I lava Environmental Focus
Nick Fetty I June 5, 2015
The WACO Community School District in southeast Iowa may soon be the state's first to be
almost completely powered by solar energy.
This summer construction is expected to begin on a solar farm behind the junior-senior high
school building in Wayland. In January the district installed a large solar collector behind the
elementary school building in Crawfordsville. School district officials expect that these two project
will provide about 90 percent of the district's electricity needs (http://viww.kcci.com/news/school-
to-be-almost-completely-solar-powered/33374210). Superintendent Darrell Smith estimates the
initial project has already saved the district about $20,000
(http://www.nonpareilonline.com/news/state/wire/solar-energy-to-power-nearly-all-of-iowa-
school-district/article_12023f93-df7d-53fb-a291-d13ef8b94f86.html). He said his hope is that these
projects will serve as not just a clean source of energy for the district but also as a learning
opportunity for the students.
"It makes it meaningful when they can see what's happening and it makes a difference when you
talk about science and green power and then say 'Let's go look at it,"' he said in an interview with
KCRG (http://www.kcrg.com/subject/news/iowas-first-fully-solar-powered-school-district-
should-happen-this-summer-20150602).
The initial solar system was funded by a one-cent local option tax. The district worked with the
Department of Education to procure funding for the second project which was possible through
private investors. Both projects took advantage of solar tax credits. On especially sunny days, the
panels are expected to generate roughly 110 percent of the districts electricity needs with the
excess energy being solar back to the utility company. Work on the second project is expected to
begin in July.
The WACO Community School District (http://Www.wacocsd.org/) serves approximately 500
students in Crawfordsville, Wayland, and the surrounding areas in Henry County.
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Article 690 • Solar Photovoltaic(PV)Systems 690.1
TABLE 685.3 Application of Other Articles
S ®
nec ARTICLE 685
Conductor/Equipment Section
Integrated Electrical Systems
More than one building or 225,Part II
other structure
I. General Ground-fault protection of 230.95,Exception
equipment
685.1 Scope Protection of conductors 240.4
This article covers integrated electrical systems,other than unit Electrical system coordination 240.12
equipment,in which orderly shutdown is necessary to ensure safe Ground-fault protection of 240.13(1)
operation.An integrated electrical system as used in this article equipment
is a unitized segment of an industrial wiring system where all of Grounding ne systems of 50 250.21
the followingconditions are met: volts to less than 1000 volts
Equipment.protection 427.22
(1) An orderly shutdown is requited to minimize personnel Orderly shutdown 430.44
hazard and equipment damage. Disconnection 430.74,Exception Nos, t and 2
(2) The conditions of maintenance and supervision ensure[hat Disconnecting means in sight 430.102(A),Exception No.2
from controller
qualified persons service the system. The name(s)of the Energy from more than one 430.113,Exception Nos. I
qualified person(s)shall be kept in a permanent record at source and 2
the office of the establishment in charge of the completed Disconnecting means 645.10,Exception
installation. Uninterruptible power supplies 645.11(1)
A person designated as a qualified person shall possess (UPS)
the skills and knowledge related to the construction and Point of connection 705.12(A)
operation of the electrical equipment and installation and
shall have received documented safety training on the haz-
ards involved.Documentation of their qualifications shall II. Orderly Shutdown
be on file with the office of the establishment in charge of
the completed installation. 685.10 Location of Overcurrent Devices
(3) Effective safeguards acceptable to the authority having in or on Premises
jurisdiction are established and maintained. Location of overcurrent devices that are critical to integrated elec-
The Integrated electrical systems commonly used In large and trical systems shall be permitted to be accessible,with mounting
complex industrial processes are designed,Installed,and operated heights permitted to ensure security from operation by unquali-
under stringent on-site engineering supervision.The control equip- lied personnel.
ment,Including overcurrent devices,is located so that it is acces-
sible to qualified personnel, but that location might not meet 685.12 Direct-Current System Grounding
—and Is not required to meet—the conditions described In the Two-wire de circuits shall be permitted to be ungrounded.
Article 100 definition of readily accessible. Locating overcurrent
devices and their associated disconnecting means so that they are 685.14 Ungrounded Control Circuits
not readily accessible to unqualified personnel Is one of the pre- Where operational continuity is required, control circuits of
ventive measures used to help maintain continuity of operation. 150 volts or less from separately derived systems shall be per-
For some Industrial processes, the sudden loss of electric mitted to be ungrounded.
power to vital equipment Is an unacceptable level of risk,and an
orderly shutdown procedure Is necessary to prevent severe equip-
ment damage,injury to personnel,or—in some extreme cases—
catastrophic failure.Orderly shutdown is commonly employed in nee ARTICLE 690
nuclear power—generating facilities, paper mills,and other areas f Solar Photovoltaic (PV) Systems
with hazardous processes.
685.3 Application of Other Articles 1. General
The articles/sections in Table 685.3 apply to particular cases of
installation of conductors and equipment,where there are orderly 690.1 Scope -
shutdown requirements that are in addition to those of this article The provisions of this article apply to solar PV electrical
or are modifications of them. energy systems, including the array eircuit(s), inverter(s), and
National Electrical Code Handbook 2014 889
690.2 Article 690 • Solar Photovoltaic(PV) Systems
Photovoltaic source circuits —-
Photovoltaic
output circuit
Fuses
00 Solar cells - - -- -
00 0
00
Module %j
Panel J
t—Array or photovoltaic
power source
EXHIBIT690.1 APV array.(Courtesy of5olarDesign Associates,LLQ
Dedicated branch circuit
R of the electric production An ac PV module consists of a single Integrated mechanical unit.
\ and distribution network
Inverter output circuit Because there is no accessible,field-installed do wiring in this sin-
au module(includes inverter) gle unit,the do PV source-circuit requirements In this Code are not
Array(of ac modules) applicable to the do wiring In an ac PV module.
ac module system Array. A mechanically integrated assembly of modules or pan-
Notes: els with a support structure and foundation, tracker, and other
1. These diagrams are intended to be a means of identification for
photovoltaic system components,circuits,and connections. Components, as required, to form adirect-current power-pro-
2. Disconnecting means required by Article 690,Part III,are not shown. during unit.
3. System grounding and equipment grounding are not shown.
See Article 690,Party An array composed of multiple panels Installed on a support
structure Is Illustrated in Exhibit 690.2.
FIGURE 690.1(a) IdentifecationofSolar Photovoltaic Systenr
Components. Bipolar Photovoltaic Array. A PV array that has two outputs,
each having opposite polarity to a common reference point or
controller(s) for such systems. [See Figure 690.1(a) and Fig- center tap.
ure 690.1(b).]Solar PV systems covered by this article may be Blocking Diode. A diode used to block reverse flow of current
interactive with other electrical power production sources or into a PV source circuit.
stand-alone, with or without electrical energy storage such as Blocking diodes are not required by this Code, although the
batteries.These systems may have ac or do output for utilization.
Instructions or labels supplied with the PV module may require
The use of photovoltaic (PV) systems as utility-Interactive or them.Blocking diodes are not overcurrent devices and may not
stand-alone power-supply systems has steadily Increased as the be substituted for any overcurrent device required by the NEC.
technology of PV equipment has evolved and Its availability has
Improved.The requirements of Article 690 cover the use of stand- Building Integrated Photovoltaics. Photovoltaic cells,devices,
alone and utility-interactive PV systems.Utility-Interactive photo- modules,or modular materials that are integrated into the outer
voltaic systems are also subject to the requirements for surface or structure of a building and serve as the outer protective
Interconnected electric power production sources contained In surface of that building.
Article 705.
Exhibit 690.1 shows a typical installation of a PV array In a field.
DC-to-DC Converter. A device installed in the PV source cir-
690.2 Definitions cuit or PV output circuit that can provide an output do voltage
and current at a higher or lower value than the input do voltage
Alternating-Current(ac)Module(Alternating-Current Pho- and current.tovoltaicModule). A complete,environmentally protected unit
consisting of solar cells,optics,inverter,and other components, Direct-Current(de)Combiner. A device used in the PV source
exclusive of tracker,designed to generate ac power when exposed and PV output circuits to combine two or more do circuit inputs
to sunlight. and provide one de circuit output.
890 2014 National Electrical Code Handbook
Article 690 • Solar Photovoltaic(PV)Systems 690.2
Photovoltaic source circuits Diversion Charge Controller. Equipment that regulates the
inverter input circuit charging process cu a battery to diverting power from energy
�/ anddlstribuifon
r output circuit
storage to direct-current or alternating-current loads or to an
Electric production interconnected utility service.
Photovoltaic output circuit network connection
Inverter Electrical Production and Distribution Network, A power
Interactive system production,distribution,and utilization system,such as a utility
Wind,engine-generator, system and connected loads,that is external to and not controlled
micro-hydro-electric,and Energy storage,charge controller, by the PV power system.
other power sources and system control
Inverter input circuit
Inverter output circuit Interactive System. A solar PV system that operates in paral-
Photovoaaic �� lel with and may deliver power to an electrical production and
output circuit distribution network.For the purpose of this definition,an energy
------------
Hybrid system do loads Inverter storage subsystem of a solar PV system,such as a battery,isnot
another electrical production source.
C arge controller
–�—� ter input circuit Inverter. Equipment that is used to change voltage level or
Photovoltaic Inverp
/c output waveform,or both,of electrical energy.Commonly,an inverter
circuit Inverter output circuit
Main supply (also known as a power conditioning unit(PCU)or power can-
equipment for version system(PCS)]is a device that changes do input to an ac
"–Inverter ac loads output.Inverters may also function as battery chargers that use
Main supply equipment alternating current from another source and convert it into direct
for do loads current for charging batteries.
Stantl-alone system Energy storage
Exhibit 690.3 shows a utility-interactive Inverter Intended for use
Notes:
I. These diagrams are intended to be a means of identification for In parallel with an electric utility.
photovoltaic system components,circuits,and connections.
2- Disconnecting means and overcurrent protection required by Inverter Input Circuit. Conductors between the inverter and
Article 690,Part til,are not shown. the battery in stand-alone systems or the conductors between the
3. System grounding and equipment grounding are not shown.
See Article 690,Part V. inverter and the PV output circuits for electrical production and
4. Custom designs occur in each configuration,and some components distribution network.
are optional.
FIGURE 690.1(b) Identification of Solar Photovoltaic System
Components in Common System Configurations.
lam,A��Y/�• ;
TTI
EXHIBIT690.2 A PV array support structure that allowsfor continued EXHIBIT 690.3 Autility-Interactive inverter.(Courtesy of SMA
use of the walkway.(Courtesy of Solar Design Associates,LLC) TechnologfesAG)
National Electrical Code Handbook 2014 691
690.3 Article 690 • Solar Photovoltaic(PV)Systems
Inverter Output Circuit. Conductors between the inverter
and be ac n the inverter
for stand-alone systems or the conduc-
tors
tors between the inverter and rite service equipment or another p G
electric power production source,such as a utility,for electrical
production and distribution network.
Module. A complete, environmentally protected unit con-
listing of solar cells,optics,and other components,exclusive I ,�
of tracker, designed to generate do power when exposed to
sunlight. - -
Y
Monopole Subarray. A PV subarray that has two conductors -
in the output circuit,one positive(+)and one negative(—).Two
monopole PV subatrays are used to form a bipolar PV array. -
MultimodeInverten Equipment having the capabilities of b(
the utility-interactive inverter and the stand-alone inverter. - - -----`�"
Panel. A collection of modules mechanically fastened together, EXHIBIT 690.4 Stand-alone system components.(Courtesy of Solar
wired,and designed to provide a field-installable unit. Design Associates,LLC)
Photovoltaic Output Circuit. Circuit conductors between the 690.4 General Requirements
PV source eircuit(s)and the inverter or do utilization equipment. (A) Photovoltaic Systems. Photovoltaic systems shall be per-
Photovoltaic Power Source. An array or aggregate of arrays mitted to supply a building or other structure in addition to any
that generates do power at system voltage and current. other electrical supply system(s).
Photovoltaic Source Circuit. Circuits between modules and
from modules to the common connection point(s) of the do (B) Equipment. Inverters,motor generators,PV modules,PV
system. panels,ac PV modules,de combiners,do-to-de converters,and
Photovoltaic System Voltage. The direct current(dc)voltage charge controllers intended for use in PV power systems shall
of any PV source or PV output.circuit. For multiwire installa- be listed for the PV application.
tions,the PV system voltage is the highest voltage between any The simplified circuit schematics In Exhibits 690.5 through 690.6
two de conductors. demonstrate the use of various components in a PV system.Spe-
cific requirements for overcurrent protection, disconnecting
Solar Cell. The basic PV device that generates electricity when means, and grounding are covered in other sections of Arti-
exposed to light. cle 690 and should not be assumed based on these drawings.
Instructions for or labels on the PV module might require addi-
tional overcurrent devices that may not be shown.
Stand-Alone System. A solar PV system that supplies power Equipment listed for marine,mobile,telecommunications,or
independently of an electrical production and distribution other applications may not be suitable for installation in perma-
network. nent PV power systems.
Exhibit 690.4 shows the controller and energy storage compo-
nents of a stand-alone system.
(C) Qualified Personnel. The installation of equipment and all
Subarray. An electrical subset of a PV array. associated wiring and interconnections shall be performed only
by qualified persons.
690.3 Other Articles Informational Note: See Article 100 for the definition of quali-
Wherever the requirements of other articles of this Code and fred person.
Article 690 differ,the requirements of Article 690 shall apply
and,if the system is operated in parallel with a primary sources) (D) Multiple Inverters. A PV system shall be permitted[o have
of electricity, the requirements in 705.14,705.16, 705.32, and multiple inverters installed in or on a single building or structure.
705.143 shall apply. Where the inverters are remotely located from each other,a direc-
tory in accordance with 705.10 shall be installed at each do PV
Exception: Solar PV systems, equipment, or iviring installed system disconnecting means, at each ac disconnecting means,
in a Hazardous(classified)location shall also comply with the and at the main service disconnecting means showing the location
applicable portions of Articles 500 through 516. of all ac and de PV system disconnecting means in the building.
892 2014 National Electrical Code Handbook
Article 690 • Solar Photovoltaic(PV)Systems 690.4
EXHIBIT 6905 Simplified circuit
schematic of a small residential
Junction box Control box stand-alone system.
Fuses in
pull-out holders ^
IT, I Charge +tic
controller —Load
a
Inverter ac
oads
— I �
« I I
� I
� I
JWBatterles II
II
II
PVmodules
---------------------------------
I
j I PV source cimuil overcusent deuce required
by 690.9(A)unless the exceptions apply
u
I I j ------Equlpmentgmunding
Current-Ilmiling fuse
EXHIBIT 690.6 Simplifled circuit
schematic of a medium-sized
Roof-mounted PV power center r. residential hybrid system.
PV modules ^ do
^ bads
Root Charge ` ^
Junction controller }
box relay
I + + ^ Ground-fault +
system r
i 0 El ^
I
� ;\ Battery
Typical subarray 1 of 5 r `.` bank
r
I I
I I
I I
I p I
I
Inverter with
F battery
Fuel cell i charger --_---
1f VIII I�III IIIIIr i N 120 Vac out
I
2401120 li
------------ swan
N
ac panelboard
-----Equipment grounding { Main disconnects
surg.m.sler / Current-limiting lose
National Electrical Code Handbook 2014 893
690.5 Article 690 • Solar Photovoltaic(PV)Systems
source and do output circuits isolated fenny buildings shall be
permitted without givand fault protection.
Junction box Ground-fault detection and interruption for the do portions of PV
;- systems should not be confused with the requirements for ac cir-
cuit GFCI protection as defined in Article 100.A GFCI Is intended
1--- PV modules Control sort for the protection of personnel In single-phase ac systems.The ac
GFCI functions to open the ungrounded conductor when a 5-MA
charge fault current Is detected.In contrast,devices meeting the require-
%oundi controller menu of 690.5 are Intended to prevent flres In do PV circuits due
etocher = do
Posed loads to ground faults,
disconnect with
current-Ilmlling
fuses `
(A) Ground-Fault Detection and Interruption. The ground
----Equipment grounding Batteries fault protection device or system shall:
Surge arrester
urrent-Iimigng lose (I) Be capable of detecting a ground fault in the PV array do
C
•• rusource circuit egtoovercurmnt current-carrying conductors and components, including
device required by890.9(A) any intentionally grounded conductors,
unless the exceptlious apply
(2) Interrupt the flow of fault current
(3) Provide an indication of the fault,and
EXHIBIT 690.7 Simplified circuit schematic of a remote-cabin do-only (4) Be listed for providing PV ground-fault protection
system.
Automatically opening the grounded conductor for measure-
ment purposes or to interrupt the ground-fault current path shall
utility required disconnect Uliliry be permitted.If a grounded conductor is opened to interrupt the
petered near metor) ground-fault current path, all conductors of the faulted circuit
disco nett -__ Inverter _ shall be automatically and simultaneously opened.
___
( (including
^' 1}1) Manual operation of the main PV de disconnect shall not
240 v out w activate the ground-fault protection device or result in grounded
I- Residential ac conductors becoming ungrounded.
e acdisconnect panelboard
(B) Isolating Faulted Circuits. The faulted circuits shall be
i- 4-28 PV .� � ,.- ac
' e modules do Electrodes bonded grounding isolated by one of the two following methods:
connected grounding together or do GEC - electrode
In series electrode connected to as conductor (1) The ungrounded conductors of the faulted circuit shall be
t e do grounding electrode (GEC)
grounding ac automatically disconnected,
electrode grounding
' conductor electrode (2) The inverter or charge controller fed by the faulted cir-
B (GEC)
.-__-_Equipment grounding nnductar chit shall automatically cease to supply power to output
_
Optimal auxiliary -"Bondingjumper yy Circuits.
grounding electrde based dnthe seceptl.n 10 a90.9A)required
(C) Labels and Markings. A warning label shall appear on the
EXHIBIT690.8 Simplified circuit schematic of a rooftop utility-interactive inverter or be applied by the installer near the
grid-connected system. ground-fault indicator at a visible location,stating the following:
WARNING
Exception: A directory shall not be required where all invert- ELECTRIC SHOCK HAZARD
ers and PV the disconnecting means are grouped at the nmin IF A GROUND FAULT IS INDICATED,
service disconnecting means. NORMALLY GROUNDED CONDUCTORS MAY
BE UNGROUNDED AND ENERGIZED
690.5 Ground-Fault Protection When the PV system also has batteries,the same warning shall
Grounded do PV arrays shall be provided with do groundfaultalso be applied by the installer in a visible location at the batter-
protection meeting the requirements of 690.5(A) through (C) ies.The warning sign(s)or label(s)shall comply with 110.21(B).
to reduce fire hazards.Ungrounded the PV arrays shall comply
with 690.35. 690.6 Alternating-Current(ac)Modules
Exception: Ground-mounted or pole-mounted PV arrays with (A) Photovoltaic Source Circuits. The requirements of Arti-
not tome than hvo paralleled source circuits and with till de cle 690 pertaining to PV source circuits shall not apply to ac
894 2014 National Electrical Code Handbook
Article 690 • Solar Photovoltaic(PV)Systems 690.7
modules.The PV source circuit,conductors,and inverters shall The voltage(both open circuit and operating)of a PV power
be considered as internal wiring of an ac module. source Increases as the temperature decreases. The installer
should note the temperature conditions for which the PV device
(B) Inverter Output Circuit. The output of an ac module shall was rated.If the anticipated lowest temperature at the installation
be considered an inverter output circuit, site Is lower than the rating condition(25"C),Table 690.7 must be
(C) Disconnecting Means. A single disconnecting means,in used to adjust the maximum open-circuit voltage of crystalline
accordance with 690.15 and 690.17,shall be permitted for the systems before conductors,overcurrent devices,and switchgear
combined ae output of one or more ac modules.Additionally, are selected.For other than crystalline systems,see the manufac-
each ac module in a multiple ac module system shall be provided turer's Instructions.
with a connector,bolted,or terminal-type disconnecting means. Where a listed PV module Includes open-circuit voltage tem-
perature coefficients In the Installation Instructions,these temper-
Utility-Interactive ac PV modules are designed to produce power ature coefficients provide a more accurate maximum system
only when they are connected to an external power source at the voltage than those from Table 690.7 and are required to be used
correct voltage and frequency. A single disconnecting means Instead of applying the table,
removes the external source and turns off all ac PV modules con- Bipolar PV systems (with positive and negative voltages)
netted to that disconnecting device. must use the sum of the absolute values of the open-circuit volt-
ages to determine the rated open-circuit system voltage.see the
definition of photovoltaic system voltage in 690.2.For example,a
(D) Overcurrent Protection. The outputcircuits of ac modules system with open-circuit voltages of+480 volts and-480 volts
shall be permitted to have overcurrent protection and conductor with respect to ground would have a system open-circuit voltage
sizing in accordance with 240.5(B)(2). of 960 volts.This voltage should be multiplied by a temperature-
dependent factor from Table 690.7,yielding a system design volt-
11. Circuit Requirements age of up to 1200 volts.The system design voltage should be
690.7 Maximum Voltage used In the selection of cables and other equipment. Certain
methods of connecting bipolar PV arrays meeting the require-
circuit
itor output circuit,
the
m System Voltage. hr voltage
sonme ments of 690.7(E)may have different requirements for calculating
circuitor output circuit,the maximum PV system voltage for that the maximum system voltage.
circuit shall be calculated as the sum of the rated open-circuit
voltage of the series-connected PV modules corrected for the (B) Direct-Current Utilization Circuits. The voltage of do
lowest expected ambient temperature.For crystalline and multi- utilization circuits shall conform to 210.6.
crystal line silicon modules,the rated open-circuit voltage shall be (C) Photovoltaic Source and Output Circuits. In one- and
multiplied by the correction factor provided in Table 690.7.This two-family dwellings,PV source circuits and PV output circuits
voltage shall be used to determine the voltage rating of cables,
disconnects,overcurrent devices,and other equipment.Where the TABLE 690.7 Voltage Correction Factors for Crystalline and
lowest expected ambient temperature is below-40'C (-40°17), Multictystalline Silicon Modules
or where other than crystalline or multictystalline silicon PV
modules are used,the system voltage adjustment shall be made Correction Factors for Ambient Temperatures Below 25'C
in accordance with the manufacturer's instructions. (77F).(Multiply the rated open circuit voltage by the
When open-circuit voltage temperature coefficients are sup- appropriate correction factor shown below.)
plied in the instructions for listed PV modules, they shall be Ambient
used to calculate the maximum PV system voltage as required Ambient
Temperature(°C) Factor Temperature(°F)
by 110.3(B) instead of using Table 690.7.
Informational Note: One source for statistically valid, lowest- 24 to 20 1.02 76 to 68
expected,ambient temperature design data for various locations is 19 to 15 1.04 67 to 59
the Extreme Annual Mean Minimum Design Dry Bulb Tempera- 14 to 10 1.06 58[050
ture Found in the ASHRAE Handbook—Fundamentals.These 9 to 5 1.08 49 to 41
temperature data can be used to calculate maximum voltage using 4to0 1.10 40 to 32
the manufacturer's temperature coefficients relative to the rating -1 to-5 1.12 31 to 23
temperature of 25°C. -6 to-10 1.14 22 to 14
A PV source is not a constant-voltage source,and the difference -11 to-15 1.16 13 to 5
between the rated operating voltage determined under controlled -16 to-20 1.18 4 to-4
laboratory conditions and the open-circult voltage under field- -21 to-25 1.20 -5 to-13-26 m-30 1.21 —14 to-22
Installed conditions can be significant.Consequently,the higher- —31 to—35 1.23 —23 to-3I
rated open-circuit voltage must be used to select circuit -36 to-40 125 -32 to-40
components with proper voltage ratings.
National Electrical Code Handbook 2014 895
690.8 Article 690 • Solar Photovoltaic(PV)Systems
that do not include larnpholders,fixtures,or receptacles shall be higher than the rated short-circuit currents for more than 3 hours
permitted to have a maximum PV system voltage up to 600 volts. near solar noon.This requirement is duplicated in the Instructions
Other installations with a maximum PV system voltage over provided with each listed module,but this factor only needs to be
1000 volts shall comply with Article 690,Part IX. applied once.A second 125-percent factor is required by 690.8(8).
PV modules in hot climates operate at temperatures of 600C
(D) Circuits over 150 Volts to Ground. Inone-andtwo-fancily to 80°C due to solar heating. Conductors with insulation types
dwellings,live parts in PV source circuits and PV output circuits rated at least 90°C should be used,and these conductors should
over 150 volts to ground shall not be accessible to other than have the ampaclty corrected in accordance with Table 310.15(8)(16)
qualified persons while energized, or Table 310.15(8)(17).
Informational Note: See 110.27 for guarding of live parts,and (2) photovoltaic Output Circuit Currents. The maximum
210.6 for voltage to ground and between conductors. current shall be the sum of parallel source circuit maximum
Conduit,closed cabinets,or enclosures that require tools to open currents as calculated in 690.8(A)(1).
them are means of limiting access to qualified persons only.
(3) Inverter Output Circuit Current. The maximum current
(E) Bipolar Source and Output Circuits. For 2-wire circuits shall be the inverter continuous output current rating.
connected to bipolar systems,the maximum system voltage shall Both stand-alone and utllity-interactive Inverters are power-
be the highest voltage between the conductors of the 2-wire limited devices. Output circuits connected to these devices are
circuit if all of the following conditions apply:
sized on the continuous-rated outputs of these devices and are
(1) One conductor of each circuit of a bipolar subarray is sol- not based on load calculations or reduced-size PV arrays or bat-
idly grounded. tery banks.Exhibit 690.9 shows an Inverter label displaying the
maximum output circuit current along with other necessary
Exception: The operation of ground-fault or arc fault devices ratings.
(abnormal operation)shall be permitted to interrupt this con-
nection to ground when the entire bipolar array becomes nvo (q) Stand-Alone Inverter Input Circuit Current. Themaxi-
distbnctarrays isolated front each other and the utilization mum current shall bethe stand-alone continuous inverter input
equipment. current rating when the inverter is producing rated power at the
(2) Each circuit is connected to a separate subarray. lowest input voltage.
(3) The equipment is clearly marked with a label as follows: Stand-alone Inverters are nearly constant-output voltage devices.
WARNING As the Input battery voltage decreases,the Input battery current
BIPOLAR PHOTOVOLTAIC ARRAY. Increases to maintain a constant ac output power.The input cur-
DISCONNECTION OF NEUTRAL rent for such inverters Is calculated by taking the rated full-power
OR GROUNDED CONDUCTORS output of the Inverter In watts and dividing It by the lowest oper-
MAY RESULT IN OVERVOLTAGE ating battery voltage and then by the rated efficiency of the
ON ARRAY OR INVERTER. inverter under those operating conditions.
The warning sign(s)or label(s)shall comply with 110.21(B).
690.8 Circuit Sizing and Current
(A) Calculation of Maximum Circuit Current. The maxi-
ModelNaF,un" .Flue-5.01 all
mum current for the specific circuit shall be calculated in accor- ® wde>. .,0,,,uw
dance with 690.8(A)(1)through(A)(5). set „
_No va000zes "
set
Informational Note: Where the requirements of 690,8(A)(1)and mw•..,p�.w 10�3°s .,,...,.
(13)(1)are both applied,the resulting multiplication factor is 156
„wa.m•w'.wWm,. ,mow
Percent.
w�+
(1) Photovoltaic Source Circuit Currents. The maximum ^°"° -"led"
^cawaW ,mv
current shall be the sum of parallel module rated short-circuit ,uro..�m,«"�"•", ,,,^
currents multiplied by 125 percent.
ne.�•0e C
�xmu..md.a,u.nn... us
The use of the array short-circuit current allows for proper sizing
of conductors to handle the current generated during extended fsso
periods of operation under a short-circuit current operating point.
The 125-percent factor is required because PV modules, PV
source circuits,and PV output circuits can deliver output currents EXHIBIT 690.9 The label of a utility-Interactive Inverter.
896 2014 National Electrical Code Handbook
Article 690 • Solar Photovoltaic(PV)Systems 690.9
For example,the input current for a 4000-W,24-volt Inverter two modules or strings of modules and overcurrent protection for
that is 85 percent efficient at 22 volts can be calculated as the conductors. The PV module manufacturer should be con-
follows: tatted for specific Information.
Ampere input= watt output
voltage x efficiency 690.9 Overeurrent Protection
- 4000 W — 214 A (A) Circuits and Equipment. PV source circuit, PV output
22 V x 0.85 circuit,inverter output circuit, and storage battery circuit con-
ductors and equipment shall be protected in accordance with the
Ripple currents might be present In the do-Input circuits ms of single- requirements of Article 240.Protection devices for PV source
phase,stand-alone inverters.These device currents might cause
nuisance operation of overcurrent devices at continuous high circuits and PV output circuits shall be in accordance with the
requirements of 690.9(B)through(E). Circuits,either ac or dc,
Inverter outputs.In such cases,the measured maximum true rms connected to current-limited supplies(e.g.,PV modules,ac out-
value of the total (ac + dc) Input current,which will be greater put of utility-interactive inverters),and also connected to sources
than the average current calculated here,should be used to deter- having significantly higher current availability (e.g., parallel
mine conductor sizes and overcurrent device ratings. strings of modules,utility power),shall be protected at the source
(5) DC-to-DC Converter Output Current. The maximum from overcurrent.
current shall be the do-to-dc converter continuous output cur- Exception: An overcurrent device shall not be required for PV
rent rating. nodules or PV source circuit conductors sized in accordance
(B) Conductor Ampacity. PV system cun'ents shall be consid- with 690.8(B)where one of the following applies:
ered to be continuous.Circuit conductors shall be sized to carry (a) There are no external sources such as parallel-connected
not less than the larger of 690.8(B)(1)or(2). source circuits, batteries, or backfeed fi'mn inverters.
(1) One hundred and twenty-five percent of the maximum (b) The short-circuit curentsfiona.all sources donot aviceedthe
currents calculated in 690.8(A)before the application of adjust- ampacity of the conductors and the maxinmu overcurrent
mint and correction factors, protective device size rating specked on the PV module
nameplate.
Exception: Circuits containing an assembly, together with its
overcurrent device(s), that is listed for continuous operatroe The conductors of the specified circuits and equipment are
required to be protected at their source of supply 0.accordance
at 100 percent of its rating shall be permitted to be used at with Article 240.The additional requirements of 690.9(0)through
100 percent of its rating.
(E) apply to PV source and output circuit conductors. Because
these circuits are subject to electrical and environmental stresses,
(2) The maximum currents calculated in 690.8(A) after the the overcurrent devices are required to be specifically listed for
application of adjustment and correction factors. use In PV systems.The overcurrent devices may be either supple-
mental or branch-circuit devices.
• In the circuits Illustrated In Exhibits 690.5 through 690.8,the
(C) Systems with Multiple.Direct-Current Voltages. For PV source-clrcult and output-circuit overcurrent devices are
a PV power source that has multiple output circuit voltages required to be rated at 125 percent of the source current calcu-
and employs a common-return conductor, the ampacity of the lated In 690.8(A). Possible backfeed currents from the other PV
common-return conductor shall not be less than the sum of the source circuits, other supply sources through the Inverter, and
ampere ratings of the overcurrent devices of the individual output storage-battery circuits,If any,have to be considered.
circuits. Each module or string of modules Is a source circuit;there-
fore,reverse-current protection Is required on nearly all PV mod-
(D) Sizing of Module Interconnection Conductors. Where a uses(as indicated by the fuse requirement labeled on the back of
single ovencun'ent device is used to protect a set of two or more each module).
parallel-connected module circuits,the ampacity of each of the Blocking diodes(possibly required by the module manufac-
moduleintercontlection conductors shallnot be less than the sum turer for specific applications) can lose their blocking ability
of the rating of the single overcurrent device plus 125 percent of because of overtemperature conditions or Internal breakdown,
the short-circuit current fromthe otherparallel-connectedmodules. Therefore,overcurrent protection has to be considered with a con-
Normally,labels or module instructions require reverse overcur- ditlon of shorted blocking diodes If they are used In the circuit.
rent protection for each module or string of modules. In some In typical one-and two-family dwelling unit utility-Interactive
cases,modules with low-rated short-circuit currents and high val- PV systems,overcurrent devices may only be required In the do
ues of the required series protective fuse may allow the use of PV source or output circuits where more than two strings of PV
one overcurrent device to provide reverse-current protection for modules are connected in parallel.
National Electrical Code Handbook 2014 897
690.10 Article 690 • Solar Photovoltaic(PV)Systems
The need for overcurrent protection at the Inverter or bat- shall be permitted without overcurrent protection from the
tery/charge controller end of the PV output circuit may depend inverter
on the maximum backfeed fault current available from other
sources. 690.10 Stand-Alone Systems
The premises wiring system shall be adequate to meet the
requirements of this Code for a similar installation connected to
(B) Overcurrent Device Ratings. Overcurrent device ratings a service.The wiring on the supply side of the building or stmc-
shall be not less than 125 percent of the maximum currents cal- lure disconnecting means shall comply with the requirements of
culated in 690.8(A). this Code,except as modified by 690.10(A)through(E).
Exception: Circuits containing an assembly, together with its (A) Inverter Output. The ac output from a stand-alone
overcurrent device(s), that is listed for continuous operation inverter(s)shall be permitted to supply ac power to the building
at 100 percent of its rating shall be permitted to be used at or structure disconnecting means at current levels less than the
100 percent of its rating. calculated load connected to that disconnect.The inverter output
Overcurrent devices may be Installed In enclosures that are rating or the rating of an alternate energy source shall be equal
exposed to direct sunlight and so may be subject to operating to or greater than the load posed by the largest single utilization
temperatures higher than 40°C.Derating may be necessary. equipment connected to the system.Calculated general lighting
loads shall not be considered as a single load.
(C) Direct-Current Rating. Overcurrent devices,either fuses
or circuit breakers,used in any do portion of a PV power system Even though a stand-alone Installation may have service-entrance
shall be listed and shall have the appropriate voltage, current, equipment rated at 100 or 200 amperes at 120/240 volts,the PV
and interrupt ratings. source Is not required to provide either the full current rating or
the dual voltages of the service equipment. A PV Installation is
Direct-current fault currents are considerably harder to Interrupt usually designed so that the actual ac demands on the system are
than ac faults.Overcurrent devices marked or listed only for ac sized to the output rating of the PV system.The Inverter output is
use should not be used in do circuits.Automotive-and marine- required to have sufficient capacity to power the largest single
type fuses,although used In do systems, might not be suitable for piece of utilization equipment to be supplied by the PV system,
use in permanently wired residential or commercial electrical but the Inverter output does not have to be rated for potential
power systems meeting the requirements of the Code. multiple loads to be simultaneously connected to it.
(D) Photovoltaic Source and Output Circuits. Listed PV (B) Sizing and Protection. The circuit conductors between the
overcurrent devices shall be required to provide overcurrent inverter output and the building or str ucture discon necting means
protection in PV source and output circuits. The overcurrent shall be sized based on the output rating of the inverter.These
devices shall be accessible but shall not be required to be read- conductors shall be protected from overcurrents in accordance
ily accessible. with Article 240.The overcurrent protection shall be.located at
(E) Series Overcurrent Protection. In grounded PV source the output of the inverter.
circuits,a single overcurrent protection device,where required, (C) Single 120-Volt Supply. The inverter output of a stand-
shall be permitted to protect the PV modules and the intercon- alone solar PV system shall be permitted to supply 120 volts to
netting conductors.In ungrounded PV source circuits complying single-phase,3-wire,120/240-volt service equipment or distribu-
with 690.35,an overcurrent protection device,where required, tion panels where there are no 240-volt outlets and where there
shall be installed in each ungrounded circuit conductor and shall are no multiwire branch circuits.In all installations,the rating
be permitted to protect the PV modules and the interconnecting of the overcurrent device connected to the output of the inverter
cables. shall be less than the rating of the neutral bus in the service
The single overcurrent device may provide both the reverse- equipment.This equipment shall be marked with the following
current protection required for the series-connected PV modules words or equivalent:
and the overcurrent protection required for the Interconnecting WARNING
conductors.
SINGLE 120-VOLT SUPPLY.DO NOT CONNECT
(F) Power Transformers. Overcurrent protection for atrans-
MULTIWIRE BRANCH CIRCUITS!
former with a source(s)on each side shall be provided in actor-
dance with 450.3 by considering first one side of the transformer, The warning sign(s)or label(s)shall comply with 110.21(B).
then the other side of the transformer,as the primary.
Multiwire branch circuits are common in one-and two-family
Exception: A power transformer with a current rating on the dwelling units.When connected to a normal 120/240-volt ac ser-
side connected toward the utility-interactive inverteroutpul,not vice, the currents In the neutral conductors of these multiwire
less than the rated continuous output current of the Inverter branch circuits(typically 14-3 AWG)subtract,or are at most no
898 2014 National Electrical Code Handbook
Article 690 • Solar Photovoltaic(PV)Systems 690.13
larger than the rating of the branch-circuit overcurrent device.If (3) Voltage and power shall be measured between any two
the electrical system consists of a single 120-volt PV power sys- conductors and between any conductor and ground.
tem Inverter supplying the two buses in the panelboard,the cur- (4) The rapid shutdown initiation methods shall be labeled in
rents In the grounded conductor for each muitiwire branch circuit accordance with 690.56(B).
add, rather than subtract. Because the two buses are in phase, (5) Equipment that performs the rapid shutdown shall be listed
there is no neutral conductor.The currents in these conductors and identified.
may be as high as twice the rating of the branch-circuit overcurFirst-
rent device,and overloading is possible. rem responders must contend with elements a PV system that
remain energized after the service disconnect
t Is opened.This
(D) Energy Storage or Backup Power System Require- rapid shutdown requirement provides a zone outside of which the
ments. Energy storage or backup power supplies are not potential for shock has been mitigated.Conductors more than
required. 5 feet inside a building or more than 10 feet from an array will be
(E) Back-Fed Circuit Breakers. Plug-in type back-fed circuit limited to a maximum of 30 V and 240 VA within 10 seconds of
breakers connected to a stand-alone or multimode inverter out- activation of shutdown. Ten seconds allows time for any do
put in stand-alone systems shall be secured in accordance with capacitor banks to discharge.Methods and designs for achieving
408.36(D).Circuit breakers marked"line"and"load"shall not proper rapid shutdown are not addressed by the NEC but Instead
be back-fed. are addressed in the product standards for this type of
equipment.
690.11 Arc-Fault Circuit Protection(Direct Current)
Photovoltaic systems with do source circuits,do output circuits, 111. Disconnecting Means
or both,operating at a PV system maximum system voltage of 690.13 Building or Other Structure Supplied
80 volts or greater, shall be protected by a listed(dc) arc-fault by a Photovoltaic System
circuit interrupter,PV type,or other system components listed to
provide equivalent protection.The PV arc-fault protection means Means shall be provided o disconnect all ungrounded do con-
shall comply with the following requirements: or the of a to system from all other conductors in a building
or other structure.
(1) The system shall detect and interrupt arcing faults resulting
from a failure in the intended continuity of a conductor,
connection,module,or other system component in the do
PV source and do PV output circuits. at
Location. The PV disconnecting means shall installed
at a readily accessible location either on the outside off a building
or structure or inside nearest the point of entrance of the system
conductors.
(2) The system shall require that the disabled or disconnected
equipment be manually restarted. Exception: Installations that comply with 690.31(F)shall be
(3) The system shall have an annunciator that provides a visual pennitted to have the disconnecting means located remote firom
indication that the circuit interrupter has operated. This the point of envy of the system conductors.
indication shall not reset automatically.
The PV system disconnecting means shall not be installed
The arc-fault protective device used to meet this requirement in bathrooms.
must be listed for do use and listed for use in PV systems. Listed
components that provide protection equivalent to arc-fault pro- These requirements generally prohibit long runs of PV source and
tection are also permitted by this requirement. output circuits Inside a building before reaching the required PV
disconnect.A short conductor run through a wall at the point of
690.12 Rapid Shutdown of PV Systems on Buildings first penetration to reach a disconnect mounted Inside the build-
Ing Is allowed.Section 690.31(G)permits these circuits to be run
PV system circuits installed on or in buildings shall include a Inside a building where Installed In metal conduit from the point
rapid shutdown function that controls specific conductors in of entrance to the system disconnecting means.
accordance with 690.12(1)through(5)as follows.
(1) Requirements for controlled conductors shall apply only (B) Marking. Each PV system disconnecting means shall be
to PV system conductors of more than 1.5 in (5 ft) in Permanently marked to identify it as a PV system disconnect.
length inside a building,or more than 3 in(10 ft)from a (C) Suitable for Use. Each PV system disconnecting means
PV array. shall not be required to be suitable as service equipment.
(2) Controlled conductors shall be limited to not more than
30 volts and 240 volt-amperes within 10 seconds of rapid (D) Maximum Number of Disconnects. The PV system dis-
shutdown initiation. connecting means shall consist of not more than six switches or
National Electrical Code Handbook 2014 899
690.15 Article 690 • Solar Photovoltaic(PV)Systems
six circuit breakers mounted in a single enclosure or in a group
of separate enclosures.
(E) Grouping. The PV system disconnecting means shall be
grouped with other disconnecting means for the system in accor-
dance with 690.13(D).A PV disconnecting means shall not be
required at the PV module or array location t r'__ -"
Where a building has multiple sources of power,such as the utll-
ity,the PV array, backup generator, and wind system, no more
than six disconnects for each source of power to the building are r—
permitted,and the disconnects for each source are required to be
grouped together.
• .y
690.15 Disconnection of Photovoltaic Equipment
Means shall be provided to disconnect equipment,such as invert- EXHIBIT690.T0 Rooftop utility interactive inverters.(Courtesy of
ers,batteries,and charge controllers,from all ungrounded con- Solar Design Associates,LLC)
doctors of all sources.If the equipment is energized from more
than one source,the disconnecting means shall be grouped and
identified.
A single disconnecting means in accordance with 690.17
shall be permitted for the combined ac output of one or more Modules
inverters or ac modules in an interactive system. --O--QUI—�
(A) Utility-Interactive Inverters Mounted in Not Readily
Accessible Locations. Utility-interactive inverters shall be
permitted to be mounted on roofs or other exterior areas that
are not readily accessible and shall comply with 690.15(A)(1) ___J Disconnecting
- -�h�--' means
through(4): PV source �—
circuits
(1) A do PV disconnecting means shall be mounted within
sight of or in each inverter.
(2) An ac disconnecting means shall be mounted within sight
of or in each inverter. -
(3) The ac output conductors from the inverter and an addi- Line side equipment allowed
tional ac disconnecting means for the inverter shall comply
with 690.13(A).
(4) A plaque shall be installed in accordance with 705.10. EXHIBIT 690.11 Equipment permitted on the PV powersource side
of the disconnecting means.
Exhibit 690.10 shows utility Interactive inverters with associated
disconnects installed on a rooftop.
source-circult conductors may be energized at any time from the
(B) Equipment. Equipment such as PV source circuit isolating PV modules.A centrally located disconnect meeting the require-
switches,overcurrent devices,do-to-dc converters,and blocking ments of 690.13(A)near the Inverter or batteries serves to discon-
diodes shall be permitted on the PV side of the PV disconnect- nect the PV source circuits from the other portions of the electric
ing means. power system.
In general,equipment that needs servicing must be disconnected (C) Direct-Current Combiner Disconnects. The do output of
from sources of supply. In a PV system, however, some equip- do combiners mounted on roofs of dwellings or other buildings
ment is permitted to be located on the PV power source side of shall have a load break disconnecting means located in the coal-
the disconnecting means. See Exhibit 690.11. Servicing the biner or within 1.8 m(6 ft)of the combiner.The disconnecting
exempted equipment might require disabling all or portions of means shall be permitted to be remotely controlled but shall be
the array as explained In the commentary following 690.18. manually operable locally when control power is not available.
A disconnecting means located In each PV source circuit or
located physically at each PV module location Is not required. (D) Maximum Number of Disconnects. The PV system dis-
located
load circuits (such as rooftop air conditioners), PV connecting means shall consist of not more than six switches or
900 2014 National Electrical Code Handbook
Article 690 • Solar Photovoltaic(PV) Systems 690.18
i
six circuit breakers mounted in a single enclosure or in a group (C) Externally Operable and Indicating. The PV discon-
of separate enclosures. netting means shall be externally operable without exposing the
operator to contact with live parts and shall indicate whether in
690.16 Fuses the open or closed position.
(A) Disconnecting Means. Disconnecting means shall be pro- (D) Disconnection of Grounded Conductor. A switch, cir-
vided to disconnect a fuse from all sources of supply if the fuse cuit breaker,or other device shall not be installed in a grounded
is energized from both directions. Such a fuse in a PV source conductor if operation of that switch, circuit breaker, or other
circuit shall be capable of being disconnected independently of device leaves the marked,grounded conductor in an ungrounded
fuses in other PV source circuits. and energized state.
Switches, pullouts, or similar devices that have suitable ratings Exception No. 1: A switch or circuit breaker that is part of
may serve as means to disconnect fuses from all sources of a ground fault detection systern required by 690.5, or that is
supply, part of an arc-fault detection/interruption system required by
(B) Fuse Servicing. Disconnecting means shall be installed 690.11. shall be permitted to open the grounded conductor
on PV output circuits where overcurrent devices (fuses) must when that switch or circuit breaker is automatically opened as
be serviced that cannot be isolated from energized circuits.The a normal function ofthe device in responding to ground faults.
disconnecting means shall be within sight of,and accessible to, Exception No.2: A disconnecting switch shall be permitted in
the location of the fuse or integral with fuse holder and shall a grounded conductor ifall of thefollowing conditions are met:
comply with 690.17.Where the disconnecting means are located (1) The switch is used only fm'PV array maintenance.
more than 1.8 in (6 ft)from the overcurrent device,a directory (2) The switch is accessible only by qualified persons.
showing the location of each disconnect shall be installed at the (3) The switch is rated for the maximunt do voltage and cur-
overcurrent device location. rent that could be present during any operation, including
Non-load-break-rated disconnecting means shall be marked ground fault conditions.
"Do not open under load:"
(E) Interrupting Rating. The building or structure discon-
690.17 Disconnect Type netting means shall have an interrupting rating sufficient for the
(A) Manually Operable. The disconnecting means for maximum circuit voltage and current that is available at the line
ungrounded PV conductors shall consist of a manually aper- terminals of the equipment, Where all terminals of the discon-
able switch(es)or circuit breaker(s).The disconnecting means netting means may be energized in the open position,a warning
shall be permitted to be power operable with provisions for sign shall be mounted on or adjacent to the disconnecting means.
The sign shall be,clearly legible and have the following words
manual operation in the event of apower-supply failure.The or equivalent:
disconnecting means shall be one of the following listed
devices: WARNING
(1) APV industrial control switch marked for use in PV ELECTRIC SHOCK HAZARDDO NOT TOUCH TERMINALS.
systems TERMINALS ON BOTH THE LINE
(2) A PV molded-case circuit breaker marked for use in PV AND LOAD SIDES MAY BE ENERGIZED
systems IN THE OPEN POSITION.
(3) A PV molded-case switch marked for use in PV systems
(4) A PV enclosed switch marked for use in PV systems The warning sign(s)or label(s)shall comply with 110.21(B).
(5) A PV open-type switch marked for use in PV systems
(6) A de-rated molded-case circuit breaker suitable for back- Exceptoil: A connector shall be permitted to be used as an ac
feed operation or a de disconnecting means,provided that it complies wilh the
(7) Ade-rated molded-case switch suitable for backfeed requirements of 690.33 and is listed and idenlifiedfor use with
specific equipment.
operation
(8) A do-rated enclosed switch 690.18 Installation and Service of an Array
(9) A de-rated open-type switch
(10) A do-rated rated low-voltage power circuit breaker Open circuiting, short circuiting, or opaque covering shall be.
used to disable an array or portions of an array for installation
Informational Note: Devices marked with"line"and"load"are and service.
not suitable for backfeed or reverse current.
- Informational Note: Photovoltaic modules are energized while
(B) Simultaneous Opening of Poles. The PV disconnecting exposed to light.Installation,replacement,or servicing of array
means shall simultaneously disconnect all ungrounded supply components while a module(s)is energized may expose persons
conductors. to electric shock.
National Electrical Code Handbook 2014 901
690.31 Article 690 • Solar Photovoltaic(PV)Systems
To prevent contact with energized parts by personnel during (1) PV Source Circuits. PV source circuits shall be identified
Installation,servicing,or other procedures,a number of methods at all points of termination,connection,and splices.
can be used to disable an array or portions of an array. One (2) PV Output and Inverter Circuits. The conductors of PV
method, used infrequently because of the expense in time and output circuits and inverter input and output circuits shall be
materials, is to cover all of the array or portions of it with an identified at all points of termination,connection,and splices.
opaque material. Care must be taken that all of the area to be
covered is shielded from light.Another method subdivides the (3) Conductors of Multiple Systems. Where the conductors
array Into smaller segments, which can be accomplished by of more than one PV system occupy the same junction box,
switches or connectors.Also see 690.33.Short-circuiting all or raceway, or equipment, the conductors of each system shall
portions of an array by means of switches or plug-in connectors, be identified at all termination,connection,and splice points.
In conjunction with the bypass diodes internal to each module, Exception: Where the identifrcationofthe conductors is evident
can also disable the array.(Bypass diodes are Incorporated In PV by spacing at-arrangement,further identification shall not be
modules for performance purposes.) required
IV. Wiring Methods (4) Grouping. Where the conductors of more titan one PV
system occupy the same junction box or raceway with aremov-
690.31 Methods Permitted able cover(s),the ac and do conductors of each system shall be
(A) Wiring Systems. All raceway and cable wiring methods grouped separately by cable ties or similar means at least once
included in this Code,other wiring systems and fittings specifi- and shall then be grouped at intervals not to exceed 1.8 in(6 ft).
cally listed for use on PV arrays,and wiring as part of a listed Exception: The requirement forgrrouping shall not apply if the
system shall be permitted.Where wiring devices with integral circuit enters from a cable or raceway unique to the circuit that
enclosures are used,sufficient length of cable shall be provided makes the grouping obvious.
to facilitate replacement.
Where PV source and output circuits operating at maxi- (C) Single-Conductor Cable.
mum system voltages greater than 30 volts are installed in read- (1) General. Single-conductor cable Type USE-2,and single-
ily accessible locations,circuit conductors shall be guarded or conductor cable listed and labeledas photovoltaic (PV)
installed in a raceway. wire shall be permitted in exposed outdoor locations in
Most PV modules do not have means for attaching raceways. PV source circuits for PV module interconnections within
These circuits may have to be made'not readily accessible' by the PV array.
use of physical barriers such as wire screening. Exception: Raceways shall be used when required by 690.31(A).
Informational Note: Photovoltaic modules operate at elevated
Most PV modules are designed for a direct series connection by
temperatures when exposed to high ambient temperatures and
to bright sunlight. These temperatures routinely exceed 70°C using factory-installed leads and connectors.To accommodate
(158°F)in many locations.Module interconnection conductors such a connection,use of a single-conductor Type USE-2 cable
are available with insulation rated for wet locations and a tem- and single-conductor cable listed and labeled for PV applications
perature rating of 90°C(194°F)or greater. is permitted In PV source circuits.Long runs of separated conduc-
(B) Identification and Grouping. PV source circuits and PV tors(with loop Inductance and distributed capacitance)and the
output circuits shall not be contained in the same raceway,cable resulting long time constants in do circuits may result In improper
tray,cable,under box,junction box,or similar fitting as conduc- operation of overcurrent devices.Running both positive and neg-
tors,feeders,branch circuits of other non-PV systems,or inverter ative conductors of each circuit and the EGC as close together as
output circuits,unless the conductors of the different systems are possible minimizes the circuit time constant. It also decreases
separated by apartition.PV system conductors shall be identified Induced currents from nearby lightning strikes.Because PV mod-
and grouped as required by 690.31(B)(t)through(4).The means ules may operate at high temperatures and are Installed in out-
of identification shall be permitted by separate color coding, door,exposed locations,the use of hlgh-temperature conductors
marking tape,tagging,or other approved means. rated for wet locations, such as USE-2,THWN-2, or RHW-2, Is
often necessary. See 310.15(B)(3)(c)for requirements on the
Aiternating-current branch-circuit conductors that supply an exte- ampacitles of conductors In circular raceways Installed on roof-
rior luminalre Installed near a roof-mounted PV array are exam- tops exposed to sunlight. Single-conductor cables listed and
ples of conductors that must not share the same raceway or cable labeled for use in PV applications will be Identified as'PV Wire;
with PV source or output circuit conductors. 'PV Cable;'Photovoltaic Wire;or'Photovoltaic Cable.'
Conductors directly related to a specific PV system,such as
those In do and ac output power circuits,are permitted in the same (2) Cable Tray. PV source circuits and PV output circuits
raceway as PV source and output conductors,provided they meet using single-conductor cable listed and labeled as photo-
the requirements of 690.31(6)(1)through(B)(4)and 300.3(C). voltaic(PV)wire of all sizes,with or without a cable tray
902 2014 National Electrical Code Handbook
Article 690 • Solar Photovoltaic(PV)Systems 690.31
marking/rating,shall be permitted in cable trays installed In accordance with 200.6(A),grounded conductors that are
in outdoor locations,provided that the cables are supported smaller than 6 AWG and used in PV source circuits are permitted
at intervals not to exceed 300 mm(12 in.)and secured at to be marked at the time of installation with a while marking at
intervals not to exceed 1.4 in(4.5 ft). all terminations.
Informational Note: Photovoltaic wire and PV cablehave a non- (G) Direct-Current Photovoltaic Source and Direct-
standard outer diameter.See Table I of Chapter 9 for conduit fill Current Output Circuits on or Inside a Building. Where do
calculations. PV source or do PV output circuits from building-integrated
systems or other PV systems are run inside a building or strue-
(D) Multiconductor Cable. Multiconductor cable Type TC-ER lure, they shall be contained in metal raceways, Type MC
or Type USE-2 shall be permitted in outdoor locations in PV metal-clad cable that complies with 250.118(10), or metal
inverter output circuits where used with utility-interactive invert- enclosures from the point of penetration of the surface of the
ers mounted in locations that are not readily accessible.The cable building or structure to the first readily accessible discon-
shall be secured at intervals not exceeding 1.8 in(6 ft).Equip- necting means. The disconnecting means shall comply with
ment grounding for the utilization equipment shall be provided 690.13(B)and(C)and 690.15(A)and(B).The wiring methods
by an equipment grounding conductor within the cable. shall comply with the additional installation requirements in
(E) Flexible Cords and Cables. Flexible cords and cables, 690.31(G)(1)through(4).
where used to connect the moving parts of tracking PV modules, The use of metal raceways,Type MC cable,or metal enclosures
shall comply with Article 400 and shall be of atype identified as Inside a building provides additional physical protection for these
a hard service cord or portable power cable;they shall be suitable circuits.Metal raceways also provide additional fire resistance
for extra-hard usage,listed for outdoor use,water resistant,and should faults develop in the cable,and they provide an additional
sunlight resistant.Allowable ampacities shall be in accordance ground-fault detection path for the ground-fault protection device
with 400.5. For ambient temperatures exceeding 30°C (86°F), required by 690.5.
the ampacities shall be derated by the appropriate factors given
in Table 690.31(E). (1) Embedded in Building Surfaces. Where circuits are
embedded in built-up,laminate,or membrane roofing materi-
(F) Small-Conductor Cables. Single-conductor cables listed als in roof areas not covered by PV modules and associated
for outdoor use that are sunlight resistant and moisture resistant equipment,the location of circuits shall be clearly marked using
in sizes 16 AWG and 18 AWG shall be permitted for module a marking protocol that is approved as being suitable for con-
interconnections where such cables meet the ampacity require- tinuous exposure to sunlight and weather.
ments of 400.5. Section 310.15 shall be used to determine the
cable ampacity adjustment and correction factors. The distance between the array and the disconnecting means
not limited by the Code.The PV circuit conductors between the PV
Because the smaller cables are not normally marked with stan- power source and the PV disconnecting means are energized
dard Code-recognized markings(such as USE-2), the PV module whenever the source Is producing power. Because of this poten-
manufacturer or Installer should verify that these cables are listed tial exposure to energized conductors,a marking Is required to
and labeled for PV use,which would Indicate that they have the warn roofers,other tradespersons,or first responders of the loca-
necessary sunlight and moisture resistance and are suitable for tion of energized PV conductors where PV source or output cir-
exposed,outdoor use. cuits are'Imbedded'or concealed by the roofing material.This
TABLE 690.31(E) Correction Factors
Ambient Temperature Rating of Conductor Ambient
Temperature Temperature
(°C) 60°C(140°F) 75°C(167°F) 90°C(194°F) 105°C(221°F) (°F)
30 1.00 1.00 1.00 1.00 86
31-35 0.91 0.94 0.96 0.97 87-95
36140 0.82 0.88 0.91 0.93 96-104
41145 0.71 0.82 0.87 0.89 105-113
46-50 0.58 0.75 0.82 0.86 114-122
51-55 0.41 0.67 0.76 0.82 123-131
56-60 - 0.58 0.71 0.77 132-140
61-70 - 0.33 0.58 0.68 141-158
71-80 - - 0.41 0.58 159-176
National Electrical Code Handbook 2014 903
690.32 Article 690 • Solar Photovoltaic(PV)Systems
requirement does not apply to conductors Installed in areas of the (I) Bipolar Photovoltaic Systems. Where the sum, without
roof covered by PV modules or other associated equipment. consideration of polarity, of the PV system voltages of the two
monopole subarrays exceeds the rating of the conductors and
connected equipment, monopole subarrays in a bipolar PV
(2) Flexible Wiring Methods. Where flexible metal conduit system shall be physically separated, and the electrical output
(FMC) smaller than metric designator 21 (trade size 3/4) or circuits from each monopole subarray shall be installed in sepa-
Type MC cable smaller than 25 mm (1 in.) in diameter con- rate raceways until connected to the inverter.The disconnecting
taining PV power circuit conductors is installed across ceil- means and overcurrent protective devices for each monopole
ings or floorjoists,theraceway or cable shall beproteeted by subarray output shall be in separate enclosures.All conductors
substantial guard strips that are at least as high as the raceway from each separate monopole subarray shall be routed in the
or cable.Where run exposed, other than within 1.8 m(6 ft) same raceway.Bipolar PV systems shall be clearly marked with
of their connection to equipment, these wiring methods shall a permanent,legible waming notice indicating that the discon-
closely follow the building surface or be protected from physi- nection of the grounded conductor(s)may result in overvoltage
cal damage by an approved means. on the equipment.
(3) Marking and Labeling Required. The following wiring Exception: Listed switchgear rated for the maximum voltage
methods and enclosures that contain PV power source conduc- benveen circuits and containing a physical barrier separating
tors shall be marked with the wording WARNING: PHOTO- the disconnecting means for each monopole subarray shall be
VOLTAIC POWER SOURCEby means of permanently affixed permitted to be used instead ofdiscomrecting+nears in separate
labels or other approved permanent marking: enclosures.
(1) Exposed raceways,cable trays,and other wiring methods (J) Module Connection Arrangement. The connection to a
(2) Covers or enclosures of pull boxes and junction boxes module or panel shall be arranged so that removal of a module
(3) Conduit bodies in which any of the available conduit open- or panel from a PV source circuit does not interrupt a grounded
ings are unused conductor connection to other PV source circuits.
(4) Marking and Labeling Methods and Locations. The If Interrupted,grounded conductors operate at the system poten-
labels or markings shall be visible after installation.The labels tial with respect to ground,and a shock hazard could result.
shall be reflective,and all letters shall be capitalized and shall
be a minimum height of 9.5 mm(3/s in.)in white on a red back- 690.32 Component Interconnections
ground.PV power circuit labels shall appear on every section of Fittings and connectors that are intended to be concealed at the
the wiring system that is separated by enclosures,walls,parti- time of on-site assembly, where listed for such use, shall be
tions,ceilings,or floors. Spacing between labels or markings, permitted for on-site interconnection of modules or other array
or between a label and a marking,shall not be more than 3 in components. Such fittings and connectors shall be equal to the
(10 ft),Labels required by this section shall be suitable for the wiring method employed in insulation, temperature rise, and
environment where they are installed. fault-current withstand, and shall be capable of resisting the
The objective of the requirements contained In 690.31(G)Is to effects of the environment in which they are used.
protect persons from Inadvertently damaging PV source and out-
put circuit conductors.Where the location of the PV circuit con- 690.33 Connectors
ductors is not obvious,fire fighters, other first responders, and The connectors permitted by Article 690 shall comply with
maintenance personnel could be exposed to shock hazards.Ven- 690.33(A)through(E).
tilating roofs containing PV source or output circuits by cutting
the membrane with saws could expose personnel to shock haz- (A) Configuration. The connectors shall be polarized and shall
ards and the building to further damage resulting from the[gni- have a configuration that is noninterchangeable with receptacles
tion of combustible members due to arcing from damaged in other electrical systems on the premises.
conductors. (B) Guarding. The connectors shall be constructed and
(H) Flexible,Fine-Stranded Cables. Flexible, fine-stranded installed so as to guard against inadvertent contact with live
cables shall be terminated only with terminals,lugs,devices,or parts by persons.
connectors in accordance with 110.14.
(C) Type. The connectors shall be of the latching or locking
The terminals,connectors,and crlmp-on lugs found on most elec- type.Connectors that are readily accessible and that are used in
trlcal equipment used In PV systems are not suitable for use with circuits operating at over 30 volts, nominal, maximum system
flne-stranded conductors.The requirements for these conductors voltage for de circuits,or 30 volts for ac circuits, shall require
are covered in 110.14, a tool for opening.
904 2014 National Electrical Code Handbook
Article 690 • Solar Photovoltaic(PV)Systems 690.41
(D) Grounding Member. The grounding member shall be (D) Conductors. The PV source conductors shall consist of
the first to make and the last to break contact with the mating the following:
connector. (1) Metallic or nonmetallic jacketed multiconductor cables
(E) Interruption of Circuit. Connectors shall be either (1) (2) Conductors installed in raceways
or(2): (3) Conductors listed and identified as PV wire installed as
exposed,single conductors,or
(1) Be rated for interrupting current without hazard to the (4) Conductors that are direct-buried and identified for direct-
operato. burial use
(2) Be a type that requires the use of a tool to open and marked
"Do Not Disconnect Under Load" or `Not for Current All cables and conductors Installed outdoors and exposed to
Interrupting." direct sunlight and wet conditions must be suitable for these con-
The two options for connectors in this requirement provide for
ditions.Conductors inside raceways Installed In wet locations are
required to be Identified or listed as suitable for wet locations.See
safe disconnection of circuit connectors either by allowing them 310.10(C)for the requirements on conductors Installed In wet loca-
to be opened under load or by requiring a warning Indicating that tions. Open, single conductors are permitted where listed and
disconnection prior to opening the connector Is necessary.Con- Identified as'Photovoltaic Wire;'Photovoltaic Cable;'PV Wire,'
nectors that can be opened or disconnected using only the hands or?V Cable.' These conductors are evaluated for use where
are not acceptable. exposed to direct sunlight and wet conditions.
690.34 Access to Boxes (E) Battery Systems. The PV power system direct-current
Junction,pull,and outlet boxes located behind modules or panels circuits shall be permitted to be used with ungrounded battery
shall be so installed that the wiring contained in them can be systems complying with 690.71(G).
rendered accessible directly or by displacement of a module(s) (F) Marking. The PV power source shall be labeled with the
or panel(s)secured by removable fasteners and connected by a following warning at each junction box,combiner box,discon-
flexible wiring system. nett,and device where energized, ungrounded circuits may be
exposed during service:
690.35 Ungrounded Photovoltaic Power Systems WARNING
Photovoltaic power systems shall be permitted to operate with ELECTRIC SHOCK HAZARD.THE DC CONDUCTORS
ungrounded PV source and output circuits where the system OF THIS PHOTOVOLTAIC SYSTEM ARE
complies with 69035(A)through(G). UNGROUNDED AND MAY BE ENERGIZED.
(A) Disconnects. All PV source and output circuit conductors The warning sign(s)orlabel(s)shall comply with 110.21(B).
shall have disconnects complying with 690,Part III.
(G) Equipment. The inverters or charge controllers used in
(B) OvereurrentProtection. All PV source and output circuit systems with ungrounded PV source and output circuits shall
conductors shall have overcurrent protection complying with be listed for the purpose.
690.9.
Many types of PV equipment are designed to operate only on
(C) Ground-Fault Protection. All PV source and output cir- grounded systems.
cuits shall be provided with a ground-fault protection device or
system that complies with 690.35(1)through(4): V Grounding
(1) Detects ground fault(s)in the PV array dc cuirem-carrying 690.41 System Grounding
conductors and components
(2) Indicates that a ground fault has occurred Photovoltaic systems shall comply with one of the following:
(3) Automatically disconnects all conductors or causes the (1) Ungrounded systems shall comply with 690.35.
inverter or charge controller connected to the faulted circuit (2) Grounded two-wire systems shall have one conductor
to automatically cease supplyingpower to output circuits grounded or be impedance grounded,andthe system shall
(4) Is listed for providing PV ground-fault protection comply with 690.5.
Aging of the conductors, dust and dirt Infiltration,and moisture (3) Grounded bipolar systems shall have the reference(center
and water Intrusion create leakage paths from the conductors to tap)conductor grounded or be impedance grounded,and
ground.These high-resistance leakage paths can result in leakage the system shall comply with 690.5.
current values less than those detected by the required ground- (4) Other methods that accomplish equivalent system protec-
fault detection device,but they can cause any ungrounded con- tion in accordance with 250.4(A) with equipment listed
ductor to become a potential shock hazard with respect to ground. and identified for the use shall be permitted to be used.
National Electrical Code Handbook 2014 905
690.42 Article 690 • Solar Photovoltaic(PV)Systems
690.45 Size of Equipment Grounding Conductors
Equipment grounding conductors for PV source and PV output
690.42 Point of System Grounding Connection circuits shall be sized in accordance with 250.122. Where no
The do circuit grounding connection shall be made at any single overcurrent protective device is used in the circuit,an assumed
point on the PV output circuitovercurrent device rated at the PV maximum circuit current shall
Inforbe used when applying Table 250.122.Increases in equipment
close as
Note: Locating the grounding connection point sytem grounding conductor size to address voltage drop considerations
close as practicable to the Pig source better'protects the system
from voltage surges due to lightning. shall not be required.An equipment grounding conductor shall
not be smaller than 14 AWG.
Exception: Systems with a 6905 groarnd fault protection.device
shall be permitted to have the required groundedconductor-to-
ground bond rade by the ground fault protection device. This 690.46 Array Equipment Grounding Conductors
bond, where internal to the ground fault equipment, shall not
be duplicated with an external connection. For PV modules,equipment grounding conductors smaller than
6 AWG shall comply with 250.120(C).
690.43 Equipment Grounding Where installed in raceways,equipment grounding conduc-
Equipment grounding conductors and devices shall comply with tors and grounding electrode conductors not larger than 6 AWG
690.43(A)through(F). shall be permitted to be solid.
(A) Equipment Grounding Required. Exposed non—current- 690.47 Grounding Electrode System
carrying metal parts of PV module frames,electrical equipment, (A) Alternating-Current Systems. If installing an acsystem,
and conductor enclosures shall be grounded in accordance with
250.134 or 250.136(A),regardless of voltage, a grounding electrode system shall be provided in accordance
with 250.50 through 250.60.The grounding electrode conductor
(B) Equipment Grounding Conductor Required. An equip- shall be installed in accordance with 250.64.
ment grounding conductor between a PV array and other equip-
ment shall be required in accordance with 250.110. grounding
n it g electrode
Systems. If installing a de system, e
grounding electrode system shall be provided in accordance
(C) Structure as Equipment Grounding Conductor. Devices with 250.166 for grounded systems or 250.169 for ungrounded
listed and identified for grounding the metallic frames of PV systems. The grounding electrode conductor shall be installed
modules or other equipment shall be permitted to bond the in accordance with 250.64.
exposed metal surfaces or otter equipment to mounting strut- A common do grounding-electrode conductor shall be
tures. Metallic mounting structures, other than building steel, permitted to serve multiple inverter's.The size of the common
used for grounding purposes shall be identified as equipment- grounding electrode and the tap conductors shall be in accordance
grounding conductors or shall have identified bonding jumpers with 250.166.The tap conductors shall be connected to the com-
or devices connected between the separate metallic sections and mon grounding-elecu'ode conductor by exothermic welding or
shall be bonded to the grounding system. with cormectors listed as grounding and bonding equipment in
(D) Photovoltaic Mounting Systems and Devices. Devices such a manner that the common grounding electrode conductor
remains without a splice or joint.
and systems used for of them PV modules that are also used An ac equipment grounding system shall be pemhitted to be
to provide grounding of the module frames shall be identified used for equipment grounding of inverters and other equipment and
for the purpose of grounding PV modeles. for the ground-fault detection reference for ungrounded PV systems.
(E) Adjacent Modules. Devices identified and listed for bond-
ing the metallic frames of PV modules shall be permitted to bond (C) Systems with cemetsPAlternating-Current ovolta and toms having
dc
the exposed metallic frames of PV modules to the metallic frames circuits and ac circuits with no direct connection between the do
of adjacent PV modules. grounded conductor and ac grounded conductor shall have a do
(F) All Conductors Together. Equipment grounding condmc- grounding system.The do grounding system shall be bonded to
tors for the PV array and structure (where installed) shall be the ac grounding system by one of the methods in(1),(2),or(3).
contained within the same raceway or cable or otherwise run with This section shall not apply to ac PV modules.
the PV array circuit conductors when those circuit conductors When using the methods of(C)(2)or(C)(3),the existing ac
leave the vicinity of the PV array, grounding electrode system shall meet tine applicable require-
To malntaln the shortest electrical time constant In each do circuit, ments of Article 250,Part III.
the EGC should be routed as closely as possible to the circuit con- Informational Note No. 1: ANSUUL 1741,Standard fo'Grvert-
ductors.This routing fadlltates the operation of overcurrent devices. ers, Converters,and Controllers for Use in hndependenr.Power
906 2014 National Electrical Code Handbook
Article 690 • Solar Photovoltaic(PV)Systems 690.50
Systems,requires that any inverter or charge controller that has and 250.54 at the location of all ground-and pole-mounted PV
a bonding jumper between the grounded do conductor and the arrays and as close as practicable to the location of roof-mounted
grounding system connection point have that point marked as a PV arrays.The electrodes shall be connected directly to the array
grounding electrode conductor(GEC)connection point.In PV frame(s) or structure. The do grounding electrode conductor
inverters,the terminals for the do equipment grounding conduc-
tors and the terminals for ac equipment grounding conductors shall be sized according to 250.166.Additional electrodes are
are generally connected to,or electrically in common with,a not permitted to be used as a substitute for equipment bonding
grounding busbar that has a marked do GEC terminal. or equipment grounding conductor requirements.The structure
Informational Note No. 2: For utility-interactive systems, the of a ground-or pole-mounted PV at-ray shall be permitted to be
existing premises grounding system serves as the ac grounding considered a grounding electrode if it meets the requirements
system. of 250.52. Roof-mounted PV arrays shall be permitted to use
(1) Separate Direct-Current Grounding Electrode System the metal frame of a building or structure if the requirements of
Bonded to the Alternating-Current Grounding Electrode 250.52(A)(2)are met.
System. A separate de grounding electrode or system shall be Exception No. ]: An array grounding electrode(s) shall not
installed, and it shall be bonded directly to the ac grounding
electrode system.The size of any bonding jumper(s)between he required where the land sewed by the army is integral with
the ac and do systems shall be based on the larger size of the the array.
existing ac grounding electrode conductor or the size of the do Exception No.2: An additional array grounding electrode(s)
grounding electrode conductor specified by 250.166. The de shall not be required if located within 1.8 in(6 ft)of the prem-
grounding electrode system conductors)or the bonding jump- ices wiring electrode.
ers to the ac grounding electrode system shall not be used as a
substitute for any required ac equipment grounding conductors. 690.48 Continuity of Equipment Grounding Systems
(2) Common Direct-Current and Alternating-Current Where the removal of equipment disconnects the bonding con-
Grounding Electrode. A do grounding electrode conductor nection between the grounding electrode conductor and exposed
of the size specified by 250.166 shall be run from the marked de conducting surfaces inthe PVsource oroutput circuit equip-
grounding electrode connection point to the ac grounding elec- ment,a bonding jumper shall be installed while the equipment
trode.Where an ac grounding electrode is not accessible, the is removed.
de grounding electrode conductor shall be connected to the ac Pv source and output circuits are energized anytime the PV mod-
grounding electrode conductor in accordance with 250.64(C)(1) ules are exposed to light.In many PV systems,the main bonding
or 250.64(C)(C)(2)or by using a connector listed for grounding jumper and the equipment grounding busbarare located Inthe
and bonding.This do grounding electrode conductor shall not Inverter or In a do power center that may require removal for
be used as a substitute for any required ac equipment ground- service.The continuity of the EM should be maintained even
ing conductors. when the equipment Is removed.
(3) Combined Direct-CmrentGroundingElectrodeCondue-
torandAlternating-CtrrentEquipmentGroundingConduc- 690.49 Continuity of Photovoltaic Source and Output
tor. An unspliced,or irreversibly spliced,combined grounding Circuit Grounded Conductors
conductor shall be run from the marked do grounding electrode Where the removal of the utility-interactive inverter or other
conductor connection point along with the ac circuit conductors equipment disconnects the bonding connection between the
to the grounding busbar in the associated ac equipment.This com- grounding electrode conductor and the PV source and/or PV
bined grounding conductor shall be the larger of the sizes specified output circuit grounded conductor, a bonding jumper shall be
by 250.122 or 250.166 and shall be installed in accordance with installed to maintain the system grounding while the inverter or
250.64(E).For ungrounded systems,this conductor shall be sized other equipment is removed.
in accordance with 250.122 and shall not be required to be larger
than the largest ungrounded phase conductor. PV source and output circuits are energized anytime the PV mod-
ules are exposed to light.The marked,grounded circuit conductors
Inverters used In PV power systems usually contain a transformer should always remain grounded because they may be energized
that Isolates the do grounded circuit conductor from the ac daily and cannot be easily disconnected from the source.In many
grounded circuit conductor.Isolation necessitates that both a do PV systems,the main bonding jumper Is located In the Inverter or
and an ac grounding system be Installed.The two grounding Sys- In a do power center that may require removal for service.The
tems are to be bonded together or have a common grounding continuity to ground of the grounded circuit conductors should be
electrode so that all ac and do grounded circuit conductors and maintained even when the equipment Is removed.
EM have the same near-zero potential to earth.
(D) Additional Auxiliary Electrodes for Array Grounding. A 690.50 Equipment Bonding Jumpers
grounding electrode shall be installed in accordance with 250.52 Equipment bondingjumpers,ifused,shall comply with 250.120(t).
National Electrical Code Handbook 2014 907
690.51 Article 690 • Solar Photovoltaic(PV)Systems
VI. Marking 690.54 Interactive System Point of Interconnection
690.51 Modules All interactive system(s) points of interconnection with other
sources shall be marked at an accessible location at the discon-
Modules shall be marked with identification of terminals or leads netting means as a power source and with the rated ac output
as to polarity, maximum overcurrent device rating for module current and the nominal operating ac voltage.
protection,and with the following ratings:
(1) Open-circuit voltage 690.55 Photovoltaic Power Systems Employing
(2) Operating voltage Energy Storage
(3) Maximum permissible system voltage Photovoltaic power systems employing energy storage shalt also
(4) Operating current be marked with the maximum operating voltage,including any
(5) Short-circuit current equalization voltage and the polarity of the grounded circuit
(6) Maximum power conductor.
690.52 Alternating-Current Photovoltaic Modules 690.56 Identification of Power Sources
Alternating-current modules shall be marked with identification
of terminals or leads and with identification of the following building
Facilities with Stand-Alone Systems. Any structure or
ratings: nildumg with a PV power system that is not connected to a utility
service source and is a stand-alone system shall have a permanent
(1) Nominal operating ac voltage plaque or directory installed on the exterior of the building or
(2) Nominal operating ac frequency structure at a readily visible location acceptable to the authority
(3) Maximum ac power having jurisdiction. The plaque or directory shall indicate the
(4) Maximum ac current location of system disconnecting means and that the structure
(5) Maximum overcurrent device rating for ac module contains a stand-alone electrical power system. The marking
protection shall be in accordance with 690,31(G).
690.53 Direct-Current Photovoltaic Power Source (B) Facilities with Utility Services and PV Systems. Buildings
A permanent label for the direct-current PV power source indicat- or structures with both utility service and a PV system shall have
ing the information specified in(1)through(5)shall be provided a permanent plaque or directory providing the location of the
by the installer at the PV disconnecting means: service disconnecting means and the PV system disconnecting
means if not located at the same location.The warning sign(s)
(1) Rated maximum power-point current. or labels)shall comply with 110.21(B).
(2) Rated maximum power-point voltage.
(3) Maximum system voltage. (C) Facilities with Rapid Shutdown. Buildings or structures
Informational Note to(3): See 690.7(A)for maximum PV sys- with both utility service and a PV system, complying with
tem voltage. 690.12, shall have a permanent plaque or directory including
(4) Maximum circuit current Where the PV power source has
[he following wording:
multiple outputs,690.53(1)and(4)shall be specified for PHOTOVOLTAIC SYSTEM EQUIPPED
each output. WITH RAPID SHUTDOWN
Informational Note to(4): See 690.8(A)for calculation ofmaxi-
mum circuit current. The plaque or directory shall be reflective, with all letters
(5) Maximum rated output current of the charge controller(if capitalized and having a minimum height of 9.5 mm('/s in.),in
white on red background.
installed).
Informational Note: Reflecting systems used for irradiance VII. Connection to Other Sources
enhancement may result in increased levelsof output current
and power. 690.57 Load Disconnect
The rated values for the PV power source can be calculated by add- A load disconnect that has multiple sources of power shall dis-
Ing voltage ratings of serles-connected modules and adding current connect all sources when in the off position.
ratings of parallel-connected modules or PV source circuits.
Some charge controllers have higher-rated output currents
than the input currents from the PV array.They reduce the Input 690.60 Identified Interactive Equipment
voltage from the PV array while Increasing the output to the Only inverters and ac modules listed and identified as interactive
battery, shall be permitted in interactive systems.
908 2014 National Electrical Code Handbook
Article 690 • Solar Photovoltaic(PV)Systems 690.71
690.61 Loss of Interactive System Power (D) Battery Nonconductive Cases and Conductive
An inverter or an ac module in an interactive solar PV system Racks. Flooded, vented, lead-acid batteries with more than
shall automatically de-energize its output to the connected elec- twenty-four 2-volt cells connected in series(48 volts,nominal)
trical production and distribution network upon loss of voltage shall not use conductive cases or shall not be installed in conduc-
in that system and shall remain in that state until the electrical tive cases.Conductive racks used to support the nonconductive
production and distribution network voltage has been restored. cases shall be permitted where no rack material is located within
A normally interactive solar PV system shall be permitted 150 mm(6 in.)of the tops of the nonconductive cases.
to operate as a stand-alone system to supply loads that have This requirement shall not apply to any type of valve-
been disconnected from electrical production and distribution regulated lead-acid(VRLA)battery or any other types of sealed
network sources, batteries that may require steel cases for proper operation.
This requirement prevents energizing of otherwise de-energized (E) Disconnection of Series Battery Circuits. Battery circuits
system conductors or output conductors of other off-site sources subject to field servicing, where more than twenty-four 2-volt
- (such as an electrical utility) and Is Intended to prevent electric cells are connected in series(48 volts,nominal),shall have provi-
shock.The ability to automatically de-energize output upon loss sions to disconnect the series-connected strings into segments of
of voltage is normally a feature of the utillty-Inletactive Inverter. 24 cells or less for maintenance by qualified persons.Non—load-
break bolted or plug-in disconnects shall be permitted.
690.63 Unbalanced Interconnections (F) Battery Maintenance Disconnecting Means. Battery
Unbalanced connections shall be in accordance with 705.100. installations,where there are more than twenty-four 2-volt cells
connected in series(48 volts,nominal),shall have a disconnect-
690.64 Point of Connection ing means,accessible only to qualified persons,that disconnects
Point of connection shall be.in accordance with 705.12, the grounded circuit conductor(s)in the battery electrical system
for maintenance.This disconnecting means shall not disconnect
VIII. Storage Batteries the grounded circuit conductor(s)for the remainder of the pho-
tovoltaic electrical system.A non—load-break-rated switch shall
690.71 Installation be permitted to be used as the disconnecting means.
(A) General. Storage batteries in a solar photovoltaic system (G) Battery Systems of More Than 48 Volts. On photovoltaic
shall be installed in accordance with the provisions of Article 480. systems where the battery system consists of more than twenty-
The interconnected battery cells shall be considered grounded four 2-volt cells connected in series(more than 48 volts,nominal),
where the photovoltaic power source is installed in accordance the battery system shall be permitted to operate with ungrounded
with 690.41.
conductors,provided the following conditions are met:
(B) Dwellings.
(1) The photovoltaic array source and output circuits shall
(1) Operating Voltage. Storage batteries for dwellings shall comply with 690.41.
have the cells connected so as to operate at a voltage of 50 (2) The do and ac load circuits shall be solidly grounded.
volts,nominal,or less. (3) All main ungrounded battery input/output circuit conduc-
Erception: Where live parts are not accessible during routine tors shall be provided with switched disconnects and over-
ballehy maintenance, a battery system voltage in accordance current protection.
with 690.7 shall be permitted. (4) A ground-fault detector and indicator shall be installed to
monitor for ground faults in the battery bank.
(2) Guarding of Live Parts. Live parts of battery systems
for dwellings shall be guarded to prevent accidental contact (H) Disconnects and Overcurrent Protection. Where energy
by persons or objects,regardless of voltage or battery type. storage device input and output terminals are more than 1.5 in
(5 ft)from connected equipment,or where the circuits from these
Informational Note: Batteries in solar photovoltaic systems are terminals pass through a wall or partition,the installation shall
subject to extensive charge-discharge cycles and typically require comply with the following:
frequent maintenance,such as checking electrolyte and cleaning
connections. (1) A disconnecting means and overcurrent protection shall be
(C) Current Limiting. A listed,current-limiting, overcurrent provided at the energy storage device end of the circuit.
device shall be installed in each circuit adjacent to the batteries Fused disconnecting means or circuit breakers shall be
where the available short-circuit current from a battery or bat- permitted to be used.
tery bank exceeds the interrupting or withstand ratings of other (2) Where fused disconnecting means are used,the line termi-
equipment in that circuit. The installation of current-limiting nals of the disconnecting means shall be connected toward
fuses shall comply with 690.16. the energy storage device terminals.
National Electrical Code Handbook 2014 909
690.72 Article 690 • Solar Photovoltaic(PV)Systems
(3) Overcurrent devices or disconnecting means shall not be rating of the diversion load shall be at least 150 percent of
installed in energy storage device enclosures where explo- the power rating of the photovoltaic array.
sive atmospheres can exist. (2) The conductor ampacity and the rating of the overcur-
(4) A second disconnecting means located at the connected rent device for this circuit shall be at least 150 percent
equipment shall be installed where the disconnecting of the maximum current rating of the diversion charge
means required by 690.71(H)(1)is not within sight of the controller.
connected equipment. Diversion loads are typically rated by the current that they will
(5) Where the energy storage device disconnecting means is draw at some rated voltage. If the rated current of the diversion
not within sight of the PV system ac and do disconnecting load exceeds the current rating of the diversion load controller,
means,placards or directories shall be installed at the loca- the controller may not function properly.
tions of all disconnecting means indicating the location of
all disconnecting means. (3) PV Systems Using Utitity-Interactive Inverters. Pho-
Clrcuils between a PV system and an energy storage device are tovoltaic power systems using utility-interactive inverters to
control battery state-of-charge by diverting excess power into
bldlYectlonal;a supply source is present on both ends of the cir•
cuit. Many energy storage devices are capable of significant the utility system shall comply with(1)and(2):
short-circuit currents.Therefore,overcurrent protection Is needed (1) These systems shall not be required to comply with
for circuits connected to these devices. 690.72(B)(2). The charge regulation circuits used shall
A disconnecting means Is required at the battery end to dis• comply with the requirements of 400.5,
connect the batteries from the circuit during equipment failure or (2) These systems shall have a second,independent means of
maintenance.Any penetration of a wall or partition necessitates controlling the battery charging process for use when the
the Installation of an additional disconnecting means at the utility is not present or when the primary charge controller
equipment end of the circuit. fails or is disabled.
690.72 Charge Control (C) Buck/Boost Direct-Current Converters. When buck/
boost charge controllers and other de power converters that
(A) General. Equipment shall be provided to control the charg- increase or decrease the output current or output voltage with
ing process of the battery. Charge control shall not be required respect to the input current or input voltage are installed, the
where the design of the photovoltaic source circuit is matched requirements shall comply with 690.72(C)(1)and(C)(2).
to the voltage rating and charge current requirements of the
interconnected battery cells and the maximum charging current (1) The ampacity of the conductors in output circuits shall be
multiplied by 1 hour is less than 3 percent of the rated battery based on the maximum rated continuous output current of
capacity expressed in ampere-hours or as recommended by the the charge controller or converter for the selected output
battery manufacturer. voltage range,
All adjusting means for control of the charging process shall (2) The voltage rating of the output circuits shall be based on
be accessible only to qualified persons. the maximum voltage output of the charge controller or
converter for the selected output voltage range.
Informational Note: Certain battery types such as valve-regulated
lead acid or nickel cadmium can experience thermal failure when 690.74 Battery Interconnections
overcharged.
(A) Flexible Cables. Flexible cables, as identified in Arti-
(B) Diversion Charge Controller. cle 400,in sizes 2/0 AWG and larger shall be permitted within
(1) Sole Means of Regulating Charging. A photovoltaic the battery enclosure from battery terminals to a nearby junction
power system employing a diversion charge controller as the box where they shall be connected to an approved wiring method.
sole means of regulating the charging of a battery shall be Flexible battery cables shall also be permitted between batteries
equipped with a second independent means to prevent over- and cells within the battery enclosure.Such cables shall be.listed
charging of the battery. for hard-service use and identified as moisture resistant.
Flexible,fine-stranded cables shall be terminated only with
(2) Circuits with Direct-Curtvnt Diversion Charge Control- terminals,lugs,devices,or connectors in accordance with 110.14.
ler and Diversion Load. Circuits containing a do diversion
charge controller and a do diversion load shall comply with IX. Systems over 1000 Volts
the following:
(1) The current rating of the diversion load shall be less than 690.80 General
or equal to the current rating of the diversion load charge Solar PV systems with a maximum system voltage over
controller. The voltage rating of the diversion load shall 1000 volts do shall comply with Article 490 and other require-
be greater than the maximum battery voltage.The power ments applicable to installations rated over 1000 volts.
910 2014 National Electrical Code Handbook
Article 692 • Fuel Cell Systems 692.4
690.81 Listing IP-Gas Is consumed.As opposed to internal combustion prime
Products listed for PV systems shall be permitted to be used and movers,the consumption of the fuel gas is via an electrochemical
installed in accordance with their listing.PV wire that is listed process rather than a combustion process.A power inverter con-
for direct burial at voltages above 600 volts,but not exceeding verts the do to ac.The Installation requirements of Article 692
2000 volts,shall be installed in accordance with Table 300.50, allow power derived from fuel cells to be safely delivered into
column 1. residential and light commercial occupancies as the sole source
of electric power or as an integrated source wlth a utility or other
690.85 Definitions power source.
For the purposes of Part VIII of this article,the voltages used to 692.2 Definitions
determine cable and equipment ratings are as follows. Fuel Cell. An electrochemical system that consumes fuel to
Battery Circuits. In battery circuits,the highest voltage expe- produce an electric current. In such cells, the main chemical
rienced under charging or equalizing conditions. reaction used for producing electric power is not combustion.
Photovoltaic Circuits. In do PV source circuits and PV output However,there may be sources of combustion used within the
circuits,the maximum system voltage. overall cell system,such as reformers/fuel processors.
Fuel Cell System. The complete aggregate of equipment used to
X. Electric Vehicle Charging convert chemical fuel into usable electricity and typically consist-
ing of areformer,stack,power inverter,and auxiliary equipment.
690.90 General Interactive System. A fuel cell system that operates in paral-
Photovoltaic systems used directly to charge electric vehicles lel with and may deliver power to an electrical production and
shall comply with Article 625 in addition to the requirements distribution network.For the purpose of this definition,an energy
of this article. storage subsystem of a fuel cell system,such as a battery,is not
another electrical production source.
690.91 Charging Equipment
Maximum System Voltage. The highest fuel cell inverter output
Electric vehicle couplers shall comply with 625.10. Personnel voltage between any ungrounded conductors present at acces-
protection systems in accordance with 625.22 and automatic sible output terminals.
de-energization of cables in accordance with 625.19 are not
required for PV systems with maximum system voltages of less Output Circuit. The conductors used to connect the fuel cell
than 80 volts de. system to its electrical point of delivery.
Informational Note: In the case of sites that have series-or
parallel-connected multiple units,the term output circuit also
S ® refers to the conductors used to electrically interconnect the fuel
neC ARTICLE 692 cell system(s).
f fuel Cell Systems Point of Common Coupling. The point at which the power
production and distribution network and the customer interface
occurs in an interactive system. Typically, this is the load side
1. General of the power network meter.
692.1 Scope Stand-Alone System. A fuel cell system that supplies power
independently of an electrical production and distribution
This article identifies the requirements for the installation of network.
fuel cell power systems,which maybe stand-alone or interactive
with other electric power production sources and may be with or 692.3 Other Articles
without electric energy storage such as batteries.These systems Wherever the requirements of other articles of this Code and
may have ac or de output for utilization. Article 692 differ, the requirements of Article 692 shall apply,
The rising demand for electric power has led to the development and,if the system is operated in parallel with a primary source(s)
of power sources that are viable alternatives to or can be Inter- of electricity, the requirements in 705.14, 705.16, 705.32, and
connected with electric utility distribution systems. Article 692 705.143 shall apply.
covers the Installation of on-premises electrical supply systems
where the power is derived from an electrochemical system that 692.4 Installation
consumes fuel to generale an electrlecurrent. (A) Fuel Cell System. A fuel cell system shall be permitted to
The principle of operation Is that direct current Is generated supply a building or other structure in addition to any service(s)
through a chemical reaction in which fuel such as natural gas or of another electricity supply system(s).
National Electrical Code Handbook 2014 911
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Raising Standards. Promoting Confidence.
PHOTOVOLTAIC ENTRY LEVEL EXAM
PASSING SCORE ACHIEVEMENT
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The individual named above has demonstrated a basic knowledge of the fundamental principles
of the application, design, installation and operation of grid-tie and stand-alone photovoltaic systems.
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DATE Ezra Auerbach, Executive Director ``
Communiand Colf7e
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Doug Brimeyer
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OSHA 10-Hour Construction 1ndustW Outreach Training
Date of Certificate: 08i29108 Conl-ac( Hours:
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Certificate Number: HMCO-269-VVIL01 Course Locaiion: Cedar Rapids, IA
Expiration Date: NA Date of Course:
08128-29I08
E arninatton: NA Respirator Name & klodef: NA
Instructor: Program Director:
Bob Downs kRon Snvder
Training for this proefam ',,as dcvclo2ed and delivered Lv the:
Hazardous Materials Training and Research Institute
6301 r.171kw000 31''P. SIN
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r=dar nao,ds, Iowa 52'-06
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Raising Standards.Promoting Confidence.
_ - The North American Board of
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does hereby certify that
PV Installation Jonathan Dwight
Professional
has satisfied the requirements and standards for the
PV Installation Professional
established by the NABCEP Board of Directors.
Certification# 042013-29
Expires June 3,2016 tVD
Donald B.Warfield,Board Chairman
NABCEP
PHOTOVOLTAIC ENTRY LEVEL EXAM
PASSING SCORE ACHIEVEMENT
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PAG 1 OF
STATE OF IOWA {SS:
DUBUQUE COUNTY
CERTIFICATION OF PUBLICATION
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i
I, Suzanne Pike, a Billing Clerk for Woodward Communications, Inc., an Iowa corporation,publisher
of the Telegraph Herald,a newspaper of general circulation published in the City of Dubuque, County
of Dubuque and State of Iowa; hereby certify that the attached notice was published in said newspaper
on the following dates: July 10, 2015, and for which the charge is $21.81.
CITY OF DUBUQUE,
PCk IQIIVA y
OFFICIAL NOTICE-
NOTICE AS, HEREBY
GIVEN that ' the
Dubuque City Council ,I
will conduct a public i
Bearing ata meeting-to {
commence:at 6:30-p.m,
on July 20„2015,in the
Historic Federal Build-
ing Council'Chambers
a Notary Public in and for Dubuque Count Iowa (second:'doer), the
Subscribed to before me
� y Ll y> > West 6th Street,pri the
this _day o , 20/, Re onngs
Request. by Gronen
Restoration,to rezone
the 1500 Block of White
`Street, from: R-2A'
Alternate two Family
Residential to District
to OCOffice Commer-
cial District:
Request by Louis
N any Public in and for Dubuque ounty, Iowa. Mlhalakis/ACE . Con-
.structlon,; t6 r62bne.
property locatgdt 46,0
464 West Locust Street
from C-1 Neighborhood
commercial District to.
� C=3 General.Commer
i cial District. - I;
Text Amendment 'i
Request by the City of I
Dubuque to amend the
Unified Development',
Code to establish
procedures for the
review of, new free -'
standing solar arrays.
Written comments 1
regardingthe above i
public hearings maybe
Wesaid
d to the City
office unf or
time: of
;public hearing.At.said.,:
,time and place of
publiC hearings all
interested citizens and
parties will be given an
opportunity to be
heard for' or against,
said actions:
Copies;of supporting`
documents for. the
p T
public hearings,are n
�,,r file'in the City'Clerk's+ Office .and may be
viewed,during regular
{ y CC m, i a F • ?, dl' working hours.
Any visual or hearing
impaired persons need-
ing special assistance
or personsmith special
accessibility needs
should contactthe City
Clerk's Office at (563)
589-4100 or'TTY (563)
690-6678 at least r48
hours 'prior to the
meeting.
Kevin S.Firnstahl,
cMC,City Clerk
It 7/10”
I
/721?//6
The reason I wished to be part of this conversation is because it appears there is a fair amount of
misunderstanding regarding free standing solar arrays and the amount of square footage they
require compared to the offset goals of avg home owners. The language in the current Unified
Building Code for the City of Dubuque lacks a great deal of clarity when it addresses the issue of
free standing solar arrays.
1. Fact 1) According to the US Energy information administration, In 2013,.the average annual
electricity consumption for a U.S. residential property was 909 kWh per month.
Fact 2) According to the NREL solar calculator an array consisting of (28) 255 watt modules
would produce 881 kWhs/mon, less than the power consumed by an avg home in the U.S.
Fact 3) The standard panel dimensions are approximately 18 sq/ft./panel.
Fact 4) The square footage of a 28 panel free standing solar array is 504 square ft. That structure
would measure approx 12'X42' and would not work on most residential roofs for a variety of
reasons.
Fact 5) By limiting a solar array to 100 sq ft it would only produce approx 157 Kwh's/mon., less
than 18 % of the avg homes usage.
Homeowners with larger lots should be allowed larger arrays as this would be consistent with the
electrical consumption of a larger than avg home on this larger than avg lot.
Fact 6) Currently, the Unified Building Code article 5-2.3 item 8 limits all structures to 40% of
total lot size.
Fact 7) In Article 7-2.14 of the Unified Building Code item "A" mentions lot size as a
consideration of satellite dish regulations but says nothing about lot size consideration for free
standing solar arrays.
In conclusion:
Limiting the size of a ground mounted solar to across the board to 100 sq./ft. without an
exceptional use permit is unrealistic and impractical due to the amount of solar panels that are
required to power the average home. This policy adds an additional barrier and expense to the
process required by home owners in the city from installing the size solar arrays their home
requires. Considering the Federal tax credits will expire in the next 17 months, this barrier is
going to greatly delay and hinder many projects from meeting the Dec 31st, 2016 deadline. This
policy is the polar opposite of what this City should be doing and fly's in the face of our
Sustainable City image.
July 20, 2015
The Honorable Mayor and City Coundil Members
Cfty of Dubuque
Historic Federal BuiJding
350 W. 6th Street
Dubuque Iowa 52001
C)EC, -NED
-
1�|`H �O �� 9: \�
.° °=��~ ... ._
City Clerk's Office
Dubuque, IA
RE: Text Amendment regulating the size of Residential Freestanding Solar Arrays
Dear Mayor and City Council Members:
I am aware the city is involved in the Iowa Statewide Solar Readiness Initiative.
Last week I called and spoke to the zoning departments in two other cities involved in the Initiative,
Des Moines and Cedar Rapids. 1 wanted to get some insight into how they were handling requestsfor
residential freestanding Solar Arrays or ground mounted Solar Arrays. I was told they were taking a
caucus approach because they had more issues than roof mounted arrays. They said there had been
very little, if any interest in them.
We recently had a neighbor that owns a solar business apply for a Special Exception permit to install
a 450 square ft. ground mounted solar array next to the business in his back yard. Several neighbors
were not in favor of this for following reasons.
1. Safety A ground array is an exposed, unprotected electrical hazard producing several thousand
watts of electricity with exposed wiring, high surface temperatures and sharp edges. They are installed
very close to the ground, usually 3ft. This particular array was to be located within 25 ft. of a children's
park with swing sets, jungle gyms and other equipment. With this packet is Exhibit A which will
reference safety issues with solar ground arrays. This article is from an alternative energy trade
publication that focus on solar, wind, biomass, fuel cells and more. The artide will list and explain 16
serious problems that can occur with ground mounted solar arrays. Note #1 refers to a fence which is
to protect from high voltage electric shock and animal damage. Note #6 refers to transformer leakage
that can cause land contamination. This article is referencing a solar farm but a residential array has the
same serious issues.
2. Glare and Noise Issue When you pointa500squaeft. piece of glass at the sun and then toward a
series of homes a common sense factor emerges, regardless what type of glass it may be. Solar arrays
have been noted to emit humming sounds, some worse than others. This noise can be heard up to 150
ft. in some cases.
3. Limits the Development of Adjacent Properties The average lot in Dubuque is approximately 6200
square ft. (6Ox1DO)with a14ODsquare ft. house on it. What if two small Iots are next to each other
and the one property owner A wants to plant trees at the edge of his property to shade his house. The
other property owner B installs a solar ground array and after a few years the trees begin to shade the
solar array. What does the city do? This may appear humorous but in California this is a major issue.
Do you discriminate and tell people with small Tots they can't have solar ground arrays or do tell them
they can't plant trees?
4. The Loss of Green Space and the Environmental Impact Picture the average 6200 square ft. lot in
Dubuque (60x 100) with a 1400 square ft. house on it, then include a 500 square ft. ground mounted
solar array. With this packet is Exhibit B and C please look at them both and note the size of the arrays.
Exhibit B is approximately 500 square ft. and If it were placed on a 6200 square ft. lot it would be
inconsistent and injurious to the other lots of similar size in the immediate area. The other lots would
lose full use and enjoyment of their properties and property values would go down. Would you want to
live next to that and view it constantly?
Conclusion
In doing considerable research we feel ground mounted solar arrays do not belong in R1 Districts.
They create more problems than they serve. Ground arrays in R1 Districts will just generate law suits
and phone calls. Restrict R1 districts to roof mounted arrays only. The industry is changing rapidly and -
in just a few years you will see solar shingles, solar windows and solar paint it is being researched now.
Don't be in a hurry to lead by mistake.
e•ectfully bmitted,
Robert Renne
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Here are 16 of the potential failures or damages that can occur on a solar farm and how they
could impact operations if not addressed in a timely manner.
Anything Can Go Wrong on a Solar Farm
Maureen McHale for | ESA Renewables
08/16n2, 12:1znw|Solar uWind | Photovoltaic optemx
When it comes to solar power plants, a critical consideration to achieving maximum power
output is the ongoing operation and maintenance (O&M) following the commissioning of
the system. Although solar installations are highly reiable and designed to run with minimal
manpower, efficiency will be lost and energy generation decreased if not maintained
properly.
Solar equipment can be kept in service for decades with regular and proper attention to all
major and ancillary features; however, many asset managers may not have a handle on
what is really needed in the day-to-day operations of a power pient. Undetected failures and
small issues impact the overall operations of the system, which leads to lost revenues and
lower energy generation compounding with each undetected, unmanaged issue.
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Protect Your Investment
Having an O&M company that can service utility scale and commercial photovoltaic
systems takes much of the stress out of the equation. Not only can this type of company
perform the necessary scheduled maintenance, they also will manage anomaly alerts,make
system repairs, evaluate network voltage and frequency, monitor and report on energy
production, and other criticai factors related to the solar array.
An O&M agreement provides a working plan to cover repairs, protect warranties, and
perform preventive maintenance. To ensure a facihty is operating at optimum efficiency
and not losing money, an O&M provider will generally install a monitoring system to not only
keep a close watch an all of the arrays working components to achieve maximum
performance, but also to analyze and report on energy production, trend costs, produce
quick budgets on site and more.
Utilizing state -of -the art technology and highly experienced solar energy engineering staff,
an O&M company has the ability to track all of the indicators and parameters to optimize
performance and to carry out the required maintenance of each solar farm.
16 Potential O&M Issues
Here are 16 of the potential failures or damages that can occur on a solar farm and how
they could impact operations if not addressed in a timely manner.
1. Perimeter Fence DamageDamage caused to the perimeter fence can immediately
have a negative effect on facility operations. Whether the damage was due to vandals,
a storm or even an animal, this is an item that needs immediate attention. Not only
can people be injured due to the high voltage produced by the system, but the
expensive equipment is at risk if intruders enter the area with intent to destroy or steal
items. Regular inspection and quick response to this is crucial for all solar farms.
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2. Ground Erosion. A naturaily occurring process in nature, soll and ground erosion are
caused by water and wind. Expected as a gradual occurrence and planned for at a
certain periodio rate,sudden erosiori can have a deleterious effect on a PV plant. Loss
of topsoil can lead to reshaping of the ground and the creation of channels, holes and
siopes in earth. This could cause racking to shift affecting the ability of panels to
generate the energy. It could also Iead to flooding and destruction of equipment.
Proper and frequent site monitoring will alert asset managers to anything out of the
ordinary happenirig that could put operations at risk.
3. Transformer Leakage. Routine maintenance that certifies that transformers are in
good condition every year helps avoid transformer leakage. A transformer leak can
cause land contamination and other safety risks. Knowing if a leak is present and
planning for maintenance to repair or replace it can be key in keeping energy
generation at a maximum. There several ways to carry out preventive maintenance in
transformers; however, monitoring transformer oil temperature, pressure and level to
prevent atransformer from leaking inthe fiutplace iethe best way toavoid down time
`ioaueo.Topreventfata|enom'aparameternangeissetondautornatioa|arnnscanbe
issued to check on site before the prob!em scales.
4,Various Inverter Damage. Taking the ow voltage, high current signals from PV panels
and converting into the voltage compatible with the utility grid, inverters are core
components of grid -connected systems. Monitoring of inverters is of high importance,
since changes to voltage and frequency may occur that affect performance as well as
the safety of those in proximity, lnverter damage may lead to the complete faUure af
the PV plant or partial string outages as a result of defective inverters. Inverter failures
are responsible for roughly 80% of PV system downtime. Clearly a response to any
inverter damage rnust be taken quickly.
5. Broken Conduit. A broken conduit poses danger of shock as well as chaos on the
operating system as charges are uncontained. When the construction of a site is
finished and the plant goes into operation, earth movements may happen as the
ground stabilizes. These movements can cause broken conduit and other issues with
cables. Measuring isolation on cables ensures underground runs are damage free.
This is important because broken conduit can cause a cable to break or damage the
insulation which can cause ofineand personal hazards.
6. Combiner Box Damage. With the ability to simplify wiring, combiner boxes combine
inputs from multiple strings of solar panels into one output circuit. Normally 4 to 12
strings are connected to a combiner boxJf damaged, they pose a safety risk as weU
as a major decrease in productivity.
7. Vegetation Overgrowth. Vegetation can transform from a benign nuisance in to a
major issue very quickly, In addition to attracting animais that then cause their own
brand of destruction, vegetation can shade cells, interfere with wiring and affect
structural integrity.
8. Cell Browning/Discoloring. In addition to providing power, UV radiation will lead to
aging in panel cells, seeri as browning and disooloration. This degradation inthe fi|nn
Ieads to impaired output and productivity
9. Panel Shading. When designing a PV plant, it is critical that trees and other
obstructions are cleared. PV celI electrical output is very sensitive 10 shade. If shaded,
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cells do not add to the power produced by the panel, but they absorb it. A shaded cell
has a much greater reverse voltage compared to the forward voltage of an illuminated
one, it can absorb the power of many cells in the string and the output wifl faU
drastically. Removal of any trees or structures causing shading will help optimize
power output.
1O.Shorted Cell. A shorted ceU can impact productivity if not addressed in a timely
manner. Production defects in semiconducting material often go undetected before
PV cells are put into solar panel assembUes. ldentifying these defects through testing
via irifrared imaging has been used for more than a decade. This efficient,
cost-effective test arid measurement methods for characterizing a cell's performance
and its electronic structure help ensure maximum energy production.
11. Natural Damage. A hall storm or hurricane can wreak havoc on a solar power plant.
Damaged panels, or wind torn racking and other equipment can severely decrease
output or completely put a system out of commission. Keeping a pulse on the severe
weather and inspecting the equipment following a storm is necessary for the overall
health of the solar farm.
12. Vandalism Damage. Vandais pose a major threat to any PV facility. Whether they are
stealing or destroying wiring, panels or other equipment, system damage can occur. A
solar farm in North Carolina had golf ball damage by a neighbor who decided to use
the array as the 18th hole. Detecting this damage through the use of solar monitoring
equipment minimized outages and losses.
13. Defective Tracker. An exceptional tool to enhance early morning and late afternoon
performance, trackers can increase total power produced by about 20-25% for a single
axis tracker and about 30% or more for a dual axis tracker. Defective trackers can
contribute significantly to lowered performance output and should be serviced as soon
as detected.
14. Racking Erosion. Eroding structures can be a nightmare for a PV facility. Once the
structural integrity is degraded, risks to proper water and wind flow within the facility
are elevated which can gravely impact the functioning of the facility. As racking
moves, panels are moved from their optimal positioning and energy generation suffers.
15.Unclean Panels. Dust, snow, pollen, leaf fragments, and even bird droppings — all can
absorb sunlight on the surface of a panel, reducing the light that reaches the cells.
Clean surfaces result in increased output performance over the lifespan of the
equipment. Routine cleaning should be a part of all O&M plans.
16. Animal Nuisance. No matter whether an animal burrows under a perimeter fence,
jumps over it or goes right through it - animals need to be kept out of a solar farm.
Once inside the perimeter, they seem to have a way of finding wires to chew and
unknowingly destroy equipment.
Having an O&M agreement for a solar farm is a must. Paired with a monitoring system ,
manyofthese issues can be prevented and energy production maximized. lfyou are an
asset manager in need of an exceptional O&M company, contact ESA Renewables.
An Ideal Partner
Customized operations and maintenance packages offecustomers a coseffective and
efficient way to keep their renewable energy systems at optimal performance levels. For
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solar farm owners that do not have the staff on site to maintain the installation, ESA
Renewables, LLC (ESA), a turnkey solar solutions provider, offers O&M contracts
customized to each solar farms needs.
ESA proudly provides financing, engineering, procurement and construction (EPC), and O&M
services to customers throughout the world. Additionally, ESA has developed its own
proprietary renewable energy monitoring system complete with a newly developed cost
project and control module and is one of the first O&M providers to offer a solar power
production guarantee. With a Iocal presence and the exterisive reach of ESAs O&M
personnel for onsite repair services, customers are ensured that outages and faults are
quickly resolved to provide optimal system performance.
Backed by years of experierice gained from their testing
facility, in the engineering of innovative productsinverter
monitoring, and site expertise, ESA has not only instatled
multi -megawatts of power, but also currently provides
ongoing O&M services for solar installations for
customers worldwide.
For more information about ESA Renewables O&M
services, their Power Productions Agreements or their
proprietary MonitorJng System, please visit their websitehttp://esarenewabies.com or call
407-268-6455.
About the Author
Maureen McHale is a Marketing Consultant located in Central Florida. Maureen has
extensive Internet marketing experience and has successfully developed, launched and
pn}nnotedpnzductoandanrvimesforcompanieoinindumLrieonangingfronohigh-teoh'to
travel, funeral and more for over fifteen years. For more information about Maureens
capabilities, please visit her website, http:/Yhirennauoeen.oumorcall 352-4O6-2Ull.
08/16/12, 12:12 PM I Solar & Wind I Photovoltaic Systems
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