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5.30 PM — Sustainable Dubuque - Greenhouse Gas Inventory Update Copyrighted June 15, 2026 City of Dubuque WORK SESSION # City Council ITEM TITLE: 5:30 PM — Sustainable Dubuque - Greenhouse Gas Inventory Update SUMMARY: Sustainable Community Coordinator Gina Bell will provide an update on the progress towards meeting the 50% by 2030 greenhouse gas emissions reduction goal as well as share information about setting a longer-term, science-based target. SUGGUESTED DISPOSITION: ATTACHMENTS: 1. MVM Memo Sustainable Dubuque Work Session — Greenhouse Gas Inventory Update 2. Staff Memo SD Quarterly Work Session Agenda GHG Inventory Update_06062026 3. DRAFT_Dubuque_report_06082026 4. FINAL Council Presentation 06082026 Page 14 of 1594 Dubuque THE CITY OF � uhA�eMa cin DuB E ; . � , I � � I. Maste iece on the Mississi t 2oo�•zoiz•zois �P Pp zoi�*zoi9 TO: The Honorable Mayor and City Council Members FROM: Michael C. Van Milligen, City Manager SUBJECT: Sustainable Dubuque Work Session — Greenhouse Gas Inventory Update DATE: June 10, 2026 Director of Sustainability Gina Bell is submitting information for the 5:30 p.m. June 15, 2026, Sustainability Dubuque Work Session. The purpose of this work session is to give an update on our progress towards meeting the 50% by 2030 greenhouse gas emissions reduction goal as well as share information about setting a longer-term, science-based target. v Mic ael C. Van Milligen MCVM:sv Attachment cc: Crenna Brumwell, City Attorney Cori Burbach, Assistant City Manager Gina Bell, Director of Sustainability Page 15 of 1594 Dubuque THE CITY OF � All-Aoerip Ciq DuB E ,:�,u .�.� , Ilm Maste iece on the Mississi i zoo�.zoiz.zois �p pp Zoi�*zoia MEMORANDUM TO: Michael C. Van Milligen, City Manager FROM: Gina Bell, Director of Sustainability SUBJECT: Sustainable Dubuque Work Session — Greenhouse Gas Inventory Update DATE: June 9, 2026 INTRODUCTION This memo is for informational purposes only in preparation for the Sustainable Dubuque Work Session on June 15, 2026. BACKGROUND The City Council adopted a 50% by 2030 greenhouse gas reduction goal in 2011. The Climate Action Plan (CAP) is a plan containing specific actions to help reduce and measure our greenhouse gas emissions (GHG). Throughout the past 15 years, the City Council has funded specific actions from the CAP, as well as provided funding to add staff capacity to the Office of Sustainability. Every three years the Office of Sustainability contracts with an outside agency to conduct a greenhouse gas inventory to track our efforts to meet our 50% reduction goal by 2030. We contracted Lotus Engineering + Sustainability to update the inventory. DISCUSSION The purpose of this work session is to give an update on our progress towards meeting the 50% by 2030 greenhouse gas emissions reduction goal as well as share information about setting a longer-term, science-based target. Of note, the GHG report is still in draft form so that we have time to fully review in its entirety. However, the emissions inventory numbers are final. REQUESTED ACTION No action needed, for informational purposes only. Page 16 of 1594 �� �� �. v, � � � � � � r � .� � ���. �# , :'� � - �.,� q. � _�. . _�ri.. ' � ��� ..��li i } � .,. � .;. ., �. r . , � � . '. :+� ,��� j- � '����A1� . . . . . . � _-� .1,. . . � �. 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' �� � � � � �,, ; . �=. � � : - . y � a ,. .�� '�Y ��,,'�c�...�._._. . >, - -si� � , Cityof Dubuque 2025 Community Greenhouse Gas Inventory Report June 2026 THE CTTY OF DuB E LOT U S Masterpiece on the Mississippi Engineering&Sustainability Page 17 of 1594 Page I ii TABLE OF CONTENTS TABLE OF CONTENTS I EXECUTIVE SUMMARY IV 2025 GHG Inventory Results iv TotalEmissions............................................................................................................................................................................iv Emissionsby Sector..................................................................................................................................................................iv Emissionsby Source..................................................................................................................................................................v Emissions Over Time v TotalEmissions 2018-2025....................................................................................................................................................v Emissions by Comparable Source 2018-2025.......................................................................................................vi TotalEmissions 2003-2025..................................................................................................................................................vi Science-Based Target vii INTRODUCTION 1 DUBUQUE'S 2025 EMISSIONS 1 Emissions Overview 2 Emissionsby Sector...................................................................................................................................................................2 Emissionsby Source..................................................................................................................................................................2 Emissions by Sector and Source......................................................................................................................................3 Normalized Metrics and Benchmarking 5 Stationary Energy 6 Transportation 7 Waste and Wastewater 7 Industrial Processes�Product Use(IPPU) 8 YEAR-OVER-YEAR TRENDS 9 SCIENCE-BASED TARGET 11 CONCLUSION 12 APPENDIX: DETAILED EMISSIONS OVER TIME 13 Page 18 of 1594 Page I iii Table of Figures Figure 1 ES. 2025 Emissions by sector.....................................................................................................................................iv Figure2 ES. 2025 Emissions by source...................................................................................................................................v Figure 3 ES.Total and comparable emissions in 2018, 2022, and 2025...........................................................v Figure 4 ES.Comparable emission sources in 2018, 2022,and 2025...............................................................vi Figure 5 ES. Emission trends from 2003 to 2025............................................................................................................vii Figure6. 2025 GHG emissions by sector..............................................................................................................................2 Figure 7. 2025 GHG emissions by source..............................................................................................................................2 Figure 8. 2025 GHG emissions by sector and source..................................................................................................3 Figure 9. 2025 stationary energy sector breakdown...................................................................................................6 Figure 10. 2025 transportation sector breakdown..........................................................................................................7 Figure 11. 2025 waste sector breakdown...............................................................................................................................8 Figure12. IPPU sector breakdown...............................................................................................................................................8 Figure 13. Total and comparable emissions in 2018, 2022,and 2025...............................................................9 Figure 14. Comparable emission sources in 2018,2022,and 2025...................................................................10 Figure 15.Year-over-year total emissions (increases and decreases).......................................................10 Figure 16. Emission trends from 2003 to 2025...................................................................................................................11 Table of Tables Table 1. 2025 GHG emissions by sector and source (mt CO2e)...........................................................................4 Table 2. Benchmarking of normalized GHG emissions metrics...........................................................................5 Table 3. 2003, 2018, 2022,and 2025 emissions comparison.................................................................................13 Cover photo from the City of Dubuque. Page 19 of 1594 Page I iv EXECUTIVE SUMMARY The City of Dubuque hired Lotus Engineering and Sustainability (Lotus) to complete a greenhouse gas (GHG) emissions inventory for community-wide emissions in 2025. Dubuque has been measuring community GHG emissions since 2003 and has an emissions reduction goal of 50% from 2003 levels by 2030. The inventory completed by Lotus for 2025 included the same sources as in previous years including the sources added in the 2022 inventory. Between 2003 and 2018, the emission sources measured by Dubuque included residential electricity, residential natural gas, commercial and industrial (C&I) electricity, C&I natural gas, gasoline on-road vehicles,diesel on-road vehicles,and landfill gas. In the 2022 inventory, Lotus added the following sources: residential propane, residential fugitive emissions, residential transmission & distribution (T&D) losses, C&I propane, C&I stationary diesel, C&I T&D losses, on-road electricity, on-road T&D losses, transit, railways, aviation, waterborne, composted waste, wastewater, and refrigerant leakage. The 2025 inventory includes those same sources. 2025 GHG Inventory Results IPPU Waste6Wastewater _ _ --'- Z/ Total Emissions 3� The City of Dubuque's GHG emissions totaled 680,236 mt COZe in 2025. This value includes emissions from all sources listed in the previous section. Dubuque's per capita emissions in 2025 totaled 11.53 mt CO2e per person. Residential Buildings Emissions by Sector ZZ% The three largest sectors,or categories,of emissions in 2025 were C&I building Figure 1 ES.2025 Emissions by sector. energy usage (43% of total emissions), transportation fuels (30%), and residential building energy usage (22%). The waste and wastewater sector and the industrial processes and product use (IPPU) sector together made up the remaining 5% of emissions. See Error! Not a valid bookmark self-reference.Error! Reference source not found. Page 20 of 1594 Pagelv Emissions by Source Breaking down sectors into individual sources, the three largest sources of emissions for Dubuque in 2025 were natural gas usage (34%of total emissions),electricity usage (29%),and �Solid Waste Railways 3� 0.43% Refrigerants 2% Propane 0.32% T&D Losses �' p� / Wastewater Building Electricity �other p qgy 29% 5% / Avtation 0.24% On-Road EleCtriCity / 0.06% � Waterborne ------ — 0.05% Compost 0.02Y, Figure 2 ES.2025 Emissions by source. on-road fossil fuel use in vehicles (29%). Solid waste made up three percent of total emissions and refrigerant leakage and T&D losses made up two percent.The remaining sources together comprised one percent of the remaining emissions. See Error! Reference source not found. Emissions Over Time Total Emissions 2018-2025 Looking at total emissions (including � s5o,000 the new sources added by Lotus), o Dubuque's emissions decreased 17 �� percent between 2018 and 2025 and � �50,000 9 percent between 2022 and 2025. �o Excluding the new sources (only o looking at comparable sources), 6 � 650,000 Dubuque's emissions decreased 22 0 percent between 2018 and 2025 and o 9 percent between 2022 and 2025. � Despite the addition of several new � 550,000 sources in 2022, Dubuque's total 2o�s 2oz2 2025 emissions are continuing to decrease Year compared to the 2018 baseline. See Figure 3 ES.Total and comparable emissions in 2018,2022,and 2025. Figure 3 ES.Figure 3 ES. Total and Page 21 of 1594 Page I vi comparable emissions in 2018,2022,and 2025. Emissions by Comparable Source 2018-2025 Focusing on comparable sources between 2018 and 2025, all emission sources decreased except for on-road gasoline and diesel vehicle emissions. Between 2022 and 2025,all emission sources decreased except for C&I natural gas,on-road diesel,and landfill emissions.See Figure 4 ES. Comparable emission sources in 2018, 2022,and 2025. Emissions reductions for electricity can be attributed to reductions in Alliant Energy's electricity emission factor. Between 2018 and 2025, the emission factor for electricity decreased 40%, from 0.538 mt CO2/MWh to 0.323 mt CO2/MWh. Note that the EPA eGRID factor was previously used before 2022 rather than an emission factor provided by Alliant Energy. Between 2022 and 2025 the Alliant Energy emission factor for electricity decreased 15%,from 0.382 mt CO2/MWh to 0.323 mt CO2/MWh. 250,000 c 200,000 m 0 > � v � d � 150,000 0 `o 0 n o` ° 100,000 0 c 0 U N E 50,000 Residential Residential Natural Commercial and Commercial and On-Road Gasoline On-Road Diesel Landfill Electricity Gas Industrial Electricity Industrial Natural Gas Emission source ■2018 2022 ■2025 Figure 4 ES.Comparable emission sources in 2018,2022,and 2025. Total Emissions 2003-2025 Looking at Dubuque's total emissions (including new sources added by Lotus in 2022),between the baseline year of 2003 and the most recent inventory year of 2025, Dubuque's emissions have decreased by 39%. Excluding the new emission sources added in 2022, Dubuque's emissions decreased by 43% between 2003 and 2025. Dubuque is still on track to meet its Page 22 of 1594 Page I vii current emissions reduction goal, regardless of emissions sources included. See Figure 5 ES. Emission trends from 2003 to 2025. 1,150,000 c a� ° 1,000,000 � s d a� � �X 0 � 850,000 c 0 � ° 680,236 0 0 700,000 U � 638,994 E 550,000 2003 2007 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2022 2025 Year �Total Emissions �Comparable Emissions Figure 5 ES. Emission trends from 2003 to 2025. Science-Based Target Although the City of Dubuque has an existing emissions reduction goal of 50%from 2003 levels by 2050, Lotus used the One Planet City Challenge's (OPCC) approach to calculate a science- based emissions reduction target for Dubuque in 2022. This approach used the US Human Development Index Score (HDI) and population growth projections,as well as the community's total scope 1 and 2 emissions and population during the baseline year of 2018. Using the methodology from OPCC, Lotus calculated Dubuque's science-based target to be a 62% emissions reduction from 2018 levels by 2030 and net-zero emissions by 2050. Page 23 of 1594 Pagell I NTRODUCTION The City of Dubuque has been tracking greenhouse gas (GHG) emissions since 2003 and has an emissions reduction goal of 50%from 2003 levels by 2030. In 2026,the City contracted with Lotus Engineering and Sustainability, LLC (Lotus) to create a community-wide GHG emissions inventory for calendar year 2025.The inventory completed by Lotus for 2025 included the same emissions sources as in previous years, including the newly added sources from the 2022 inventory. Between 2003 and 2018, the emission sources measured by Dubuque included residential electricity, residential natural gas,commercial and industrial (C&I) electricity,C&I natural gas, gasoline on-road vehicles,diesel on-road vehicles,and landfill gas. In the 2022 inventory,Lotus added the following sources: residential propane, residential fugitive emissions, residential transmission&distribution (T&D) losses,C&I propane,C&I stationary diesel,C&I T&D losses,on- road electricity, on-road T&D losses, transit, railways, aviation, waterborne, composted waste, wastewater, and refrigerant leakage. Those newly added sources were included in the 2025 inventory as well.Throughout the report,"total emissions"will refer to all calculated sources of emissions for 2025. "Comparable emissions" will refer to only the sources of emissions that Dubuque has tracked since 2003 and does not include the sources added in 2022. Lotus used the Global Protocol for Community-Scale Greenhouse Gas Emissions Inventories (GPC) to calculate Dubuque's 2025 emissions.The GPC allows cities and local governments to develop a robust, transparent, and globally accepted framework to consistently identify, calculate, and report on city greenhouse gas emissions. The following report will provide Dubuque with an overview of the 2025 inventory process, an analysis of city-wide emissions, and an assessment of year-over-year trends that can be used to inform future emission reduction strategies. DUBUQUE'S 2025 EMISSIONS Dubuque's community-wide GHG emissions in 2025 totaled 680,236 mt COZe.This equates to a nine percent decrease compared to the last inventory year of 2022 and a 39%decrease compared to the baseline year of 2003.The majority of 2025 emissions came from building energy use and on-road transportation fuel use. Page 24 of 1594 Page12 Emissions Overview Emissions by Sector IPPU Waste�Wastewater _ _ 2� The three largest emission sectors in 3% 2025 were C&I building energy usage (296,813 mt COZe or 43% of total emissions), transportation (203,541 mt COZe or 30%), and residential building energy usage (148,132 mt CO2e or 22%). The waste and wastewater sector and the industrial processes and product use (IPPU) sector made up the Residential remaining total emissions (20,414 mt B"''d'"9S zs i COZe or 3%and 11,336 or 2%respectively). See Figure 6.2025 GHG emissions by sector. Figure 6.2025 GHG emissions by sector. Emissions by Source Breaking down sectors into individual sources, the three largest sources of emissions for Dubuque in 2025 were natural gas usage (228,974 mt CO2e or 34%of total emissions),on-road fossil fuel vehicles (197,331 mt CO2e or 29%),and electricity usage (194,351 mt CO2e or 29%).Solid waste and refrigerant leakage in buildings each made up three percent and two percent of total emissions (18,357 mt CO2e and 11,336 mt CO2e, respectively), and the remaining sources together comprised three percent of total emissions. See Figure 7.2025 GHG emissions by source. Solid Waste Railways 3% 0.43% Refrigerants 2% Propane 0.32% T&D Losses Building Electricity other Z� Wastewnter - 0.28"/0 29% 5% 1 jr Aviation j ! 0.24Y / �' . On-ROqd EleCtriCity ��,,-/,;/ � 0.06% � ��� Waterborne 0.05% �Compost 0.02/ Figure 7.2025 GHG emissions by source. Page 25 of 1594 Page13 Emissions by Sector and Source The following figure combines emission sectors and sources. The figure separates residential building energy usage from commercial and industrial (C&I) building energy usage,as well as on-road gasoline vehicles from on-road diesel vehicles.This provides a more detailed analysis of emission sources. See Figure 8. 2025 GHG emissions by sector and source.Separating the categories of building energy usage and on-road fossil fuel vehicles,the three largest emission sources for Dubuque in 2025 were C&I electricity usage including transmission and distribution losses (145,048 mt CO2e or 21%),C&I natural gas usage (144,465 mt CO2e or 21%),and on-road gasoline vehicles (142,659 mt CO2e or 21%). Residential Propane 0.05% Industrial Processes and Product Use Residential Fugitive 2% ) � Emissions Wastewater (� 0.5% 0.3% � ReSidential � Noturol Gos � I compost 12% i/ � 0.02% � Landlilled \\ . 3% - � Wa[erborne 0.05q Aviption 0.2Y Railways 0.4q Transit 0.1% On-Road Commercial Natural Gasoline Gas On-Road Electricity 21y Z�� 0.06% On-Road Diesel I 8% Commercial Fugitive Emissions Commerciol Propone 0.8% 0.3Y Figure 8.2025 GHG emissions by sector and source. The following table lists all emission sectors and sources by total emissions in mt CO2e and percentage of total emissions. See Table 1. 2025 GHG emissions by sector and source (mt CO2e).For comparison between 2003,2018,2022,and 2025 emission sources,see Table 3 in the Appendix. Page 26 of 1594 Page I 4 Table l.2025 GHG emissions by sector and source (mt CO2e). . . . . - . . . Residential Fuel Use 148,279 21.80% Residential Electricity 60,304 8.87% Residential Natural Gas 84,509 12.42% Residential Propane 354 0.05% Residential Fugitive Emissions 3,112 0.46% Commercial and Industrial Fuel Use 296,666 43.61% Commercial and Industrial Electricity 145,048 21.32% Commercial Natural Gas 144,465 21.24% Commercial Propane 1,834 0.27% Commercial Fugitive Emissions 5,319 0.78% Transportation 203,541 29.92% On-Road Gasoline 142,659 20.97% On-Road Diesel 54,652 8.03% On-Road Electricity 433 0.06% Transit 894 0.13% Railways 2,928 0.43% Aviation 1,622 0.24% Waterborne 351 0.05% Waste 20,414 3.00% Landfilled 18,357 2.70% Compost 133 0.02% Wastewater 1,924 0.28% Industrial Processes and Product Use 11,336 1.67% Refrigerant Leaks 11,336 1.67% Total 680,236 100% *Note that transmission and distribution/osses have been combined with e%ctricity use in the residential, commercia/, and on-road sectors. Page 27 of 1594 Page I 5 Normalized Metrics and Benchmarking Below are normalized metrics' for Dubuque's 2025 GHG emissions, as well as normalized metrics for other cities in the region. See Table 2. Benchmarking of normalized GHG emissions metrics.These data help to situate Dubuque amongst its neighboring and similar cities in terms of emissions. It is important to note that not all cities listed below have updated inventories for 2025, so their most recent inventory data were used. Table 2. Benchmarking of normalized GHG emissions metrics. . - . . . . . . - . . - . . . . . . . . - • - Dubuque,IA 2025 58,987 680,236 11.53 26.35 22.24 Bozeman,MT 2024 56,114 705,542 12.57 27.23 19.64 Appleton,WI 2024 74,439 806,790 10.84 25.79 19.97 Eagan,MN 2022 67,526 919,762 13.62 32.00 22.24 Minnetonka,MN 2022 53,529 700,857 13.09 28.44 23.00 Lakeville,MN 2022 74,551 520,850 6.99 19.10 13.07 Eden Prairie,MN 2022 63,623 762,715 11.99 29.36 21.10 Stationary Energy Building energy use, or stationary energy, emissions made up 65% of Dubuque's total emissions in 2025. C&I natural gas usage was the largest source of stationary energy emissions (144,465 mt CO2e or 32% of total stationary energy emissions). This source was followed by C&I electricity usage (137,278 mt CO2e or 31%),residential natural gas usage(84,509 T6D Losses 3% /. % i ,� Commercial Other Electrieity yy, 31% Commercial Propane 0.41% Residential Propane 0.08% ' Norrr = net gener Figure 9.2025 stationary energy sector breakdown. sions per pE Page 28 of 1594 PaaP I 6 mt CO2e or 19%), and residential electricity usage (57,073 mt CO2e or 13%). The remaining stationary energy sources made up five percent of total stationary energy emissions. See Figure 9. 2025 stationary energy sector breakdown. Compared to the last inventory year of 2022, residential electricity emissions have decreased by 22%and residential natural gas emissions have decreased by 10%.C&I electricity emissions have decreased by 14% and C&I natural gas emissions have increased by 2%. Since the baseline year of 2003,both C&I electricity and residential electricity emissions have decreased by 69%, C&I natural gas emissions have increased by 15%, and residential natural gas emissions have decreased by 23%. Emissions from natural gas will decrease if more homes and businesses convert from natural gas furnaces, stoves, and water heaters to electric heat pumps. Much of the decrease in electricity emissions has been possible due to Alliant Energy's work to add renewable energy to the electric grid. Between 2022 and 2025,the emission factor for electricity decreased from 0.382 mt CO2/MWh to 0.323 mt CO2/MWh; this is a 15% decrease from 2022. Additionally, the 2025 inventory was the first inventory to receive renewable energy generation data from Alliant Energy from photovoltaic systems throughout the community. Electricity emissions will also continue to decrease as these systems become more prevalent moving forward. Transportation Transportation emissions made up 30% of Dubuque's total emissions in 2025. The largest source of transportation emissions was on-road gasoline vehicles (142,659 mt CO2e or 70% of total transportation emissions). This was followed by on-road diesel vehicles (54,652 mt CO2e or 27%). All other sources of transportation emissions made up three percent of all On-Road Diesel 27% Other 3� On-Road Electricity 0.2% �terba 0.2% ��T&D Loss 0.01� Figure 10.2025 transportation sector breakdown. Page 29 of 1594 Page17 transportation emissions. See Figure 10.2025 transportation sector breakdown. The only transportation sources comparable to past inventories are on-road gasoline and diesel vehicles. Emissions from gasoline vehicles decreased by 15% between 2022 and 2025 and have increased by 6%since 2003. Emissions from diesel vehicles increased by 8% between 2022 and 2025 and have increased by 57% since 2003. Note that activity data between 2022 and 2025 uses different methodology as Google EIE data is updating their methodology and data will not be available for 2025. The 15% decrease in gasoline vehicle emissions between 2022 and 2025 could be attributed to an increase in electric vehicles (EV) and plug-in hybrid electric vehicles (PHEV). There were an estimated 288 registered battery electric vehicles in Dubuque in 2025, a 197% increase from the estimated 97 registered EVs in 2022. In 2025, Dubuque's EV/PHEV registrations were up 299 from 2022 totals. Additionally, Dubuque Airport operated commercial flights in 2025. No commercial flights operated in previous inventory years, and commercial flights ceased in 2026. Subsequent inventories will most likely reflect a decrease in aviation emissions. Waste and Wastewater Waste and wastewater emissions made up three percent of Dubuque's total emissions in 2025.The Dubuque Metropolitan Area landfill falls �compost inside city limits, so all emissions from the landfill o.7°io . ,. are attributable to Dubuque. Emissions from the � landfill made up most of the waste and wastewater emissions (18,357 mt CO2e or 90%). �wastewaeer Wastewater made up nine percent (1,924 mt 9��� CO2e) and composted waste made up less than one percent (133 mt CO2e). See Figure 11. 2025 waste sector breakdown.Although all landfill emissions are attributable to the city, 12% of landfilled waste tonnage is directly attributable to Dubuque residents. Dubuque's past inventories did track emissions from the landfill; however, they did not track emissions from composting or wastewater treatment processes. Landfill emissions have increased by 13% since 2022 and decreased by 78% Figure 11.2025 waste sector breakdown. since 2003. The landfill began capturing landfill gas several years ago,significantly reducing emissions. Page 30 of 1594 Page18 Industrial Processes & Product Use (IPPU) IPPu emissions made up two percent of Dubuque's total emissions in 2025. The only source of IPPU emissions calculated Residential for Dubuque was refrigerant leakage from Refrigerant Leakage Commercial commercial and residential systems. 52r� �Ref��ge�pnt i Leakage Residential refrigerant leakage made up � 48, 52% of total IPPU emissions (5,922 mt CO2e) and commercial refrigerant leakage made up 48% of total IPPU emissions (5,414 mt CO2e). See Figure 12. IPPU sector breakdown. Figure 12. IPPU sector breakdown. YEAR-OVER-YEAR TRENDS There are two ways to compare the year- over-year GHG emissions totals for � 850,000 Dubuque: total emissions and ° � � comparable emissions. Total emissions � -0 750,000 include all emission sources for each o � inventory year. This includes the new o � sources added by Lotus to the 2022 ° s5o,000 inventory. Comparable emissions only ° look at sources that are directly � comparable between all inventories. This � 550,000 does not include the new sources added 2o�a 2022 2025 Year In 2022. ■Total Emissions Comparable Emissions Looking pt totpl emissions, Dubuque's Figure 13.Total and comparable emissions in 2018,2022,and emissions decreased nine percent 2025. between 2022 and 2025. Excluding the new sources (only looking at comparable sources), Dubuque's emissions decreased nine percent between the two years. See Figure 13. Total and comparable emissions in 2018, 2022, and 2025.In other words,despite the addition of several new sources, Dubuque's total emissions still decreased. Only looking at comparable emission sources between 2022 and 2025, all emission sources decreased except for C&I natural gas usage, on-road diesel, and landfill emissions. Between Page 31 of 1594 Page I 9 2018 and 2025,all emission sources decreased except for on-road gasoline and on-road diesel. VMTs continue to increase, but on-road gasoline emissions do not follow the same trend as on-road diesel emissions.This could potentially indicate a larger transition of gasoline vehicles to electric vehicles, likely due to the availability of federal tax credits and a wider variety of vehicles available for purchase. Diesel vehicles, which oftentimes consist of large trucks or buses, are being electrified at a slower rate than passenger vehicles, leading to a continued, steady increase in emissions. See Figure 14. Comparable emission sources in 2018,2022,and 2025. zso,000 � zoo,000 d 0 > � v m w D 150,000 0 V 7 O � O � IOO,OOO 0 c 0 U � 5�,��a � Residential Residential Natural Commercial and Commercial and On-Road Gasoline On-Road Diesel Landfill Electricity Gas Industrial Elec[ricity Industrial Natural Gas Emission source ■2018 2022 ■2025 Figure 14.Comparable emission sources in 2018,2022,and 2025. Dubuque's total emissions have decreased by 39% between the baseline year of 2003 and the Increase �Decrease�io[al 1,200,000 I,100,000 ■ m . � o ■? I,000,000 � � . ■ � 39%decrease a in emissions n 900,00o since 2003 0 0 ` � i � aoo,000 , E 700,000 ■ . 600,000 Figure 15.Year-over-year total emissions (increases and decreases). Page 32 of 1594 Page I 10 most recent inventory year of 2025. Excluding the new emission sources, Dubuque's comparable emissions decreased by 43% between 2003 and 2025. See Figure 15.Year-over-year total emissions (increases and decreases).Figure 15 and Figure 16 Dubuque is currently on track to meet the goal of 50%emissions reductions from 2003 levels by 2030. 1,150,000 c d a 1,000,000 3 6 N N U x O 'a 850,000 c 0 4 ° 680,236 0 0 700,000 U � 638,994 E 550,000 2003 2007 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2022 2025 Year �Total Emissions tComparable Emissions Figure 16. Emission trends from 2003 to 2025. SCIENCE-BASED TARGET As a part of the scope of work in 2022, Lotus developed a Science-Based Target for the City to consider adopting. Lotus used the One Planet City Challenge's (OPCC)2 � ' ' � approach to calculate a science-based emissions : • - • • • - reduction target for Dubuque. This approach uses several values to calculate the target, including the US Human • Development Index Score (HDI), population growth � • projections, and the community's total scope 1 and 2 emissions and population during the baseline year. _� � � � ; _ _ � Dubuque's baseline year is 2018. Using the methodology � � from OPCC, Lotus calculated Dubuque's science-based target to be a 62% emissions reduction from 2018 levels by 2030. Dubuque's 2018 emissions totaled 819,408 mt COZe; a 62% reduction in emissions would mean 2030 emissions equaling approximately 311,000 mt CO2e. 2 See: https:�/wwf.panda.or�projects/one planet cities/one planet city challen�e/. Page 33 of 1594 Page I 11 CONCLUSION Monitoring greenhouse gas emissions is a vital step in working towards a more sustainable community. Dubuque will need to continue tracking emissions over time in order to identify trends and learn the impacts of emission reduction work enacted by the City.This sustainability work will help Dubuque become more resilient to the changing climate and will serve as an example for other communities to begin similar work. Page 34 of 1594 Page I 12 APPENDIX: DETAILED EMISSIONS OVER TIME Table 3.2003,2018,2022,and 2025 emissions comparison. � � . � � . • • - • - • - • - • - Residential Fuel Use 295,023 202,896 172,693 148,124 Residential Electricity 184,805 88,832 72,640 56,926 Residential Natural Gas 110,218 114,064 93,455 84,509 Residential Propane N/A N/A 447 354 Residential Fugitive N/A N/A 3,461 3,112 Emissions Residential T&D Losses N/A N/A 2,690 3,222 Commercial and Industrial Electricity Fuel 575,374 385,074 316,018 296,821 Use Commercial and 450,118 219,369 160,596 137,425 Industrial Electricity Commercial and 125,256 165,704 141,689 144,465 Industrial Natural Gas Commercial and N�A N�A 2,539 1,834 Industrial Propane Commercial and N�A N�A 0 0 Industrial Stationary Diesel Commercial and Industrial Fugitive N/A N/A 5,247 5,319 Emissions Commercial and N/A N/A 5,946 7,778 Industrial T&D Losses Transportation 169,881 167,132 224,956 203,541 On-Road Gasoline 134,980 168,137 168,137 142,659 On-Road Diesel 34,901 36,523 50,456 54,652 On-Road Electricity N/A N/A 367 410 On-Road Electricity T&D N/A N/A 14 23 Losses Transit N/A N/A 932 894 Page 35 of 1594 I 13 Railways N/A N/A 3,846 2,928 Aviation N/A N/A 932 1,622 Waterborne N/A N/A 273 351 Waste 82,319 64,305 18,101 20,414 Landfilled 82,319 64,305 16,297 18,357 Compost N/A N/A 96 133 Wastewater N/A N/A 1,708 1,924 Industrial Processes and Product Use N/A N/A 12,344 11,336 Refrigerant Leaks N/A N/A 12,344 11,336 All Emissions Total 1,122,597 819,408 744,112 680,236 Comparable Emissions 1,122,597 819,408 703,270 638,994 Total Page 36 of 1594 . , „iiIII111N Cit of Du bu ue s y q 2025 G reen house � � 1 Gas E m � ssions � � � ��� t +.,�,"��_��` � - �_ - � ��� �: � � :-�,��;;�� � .� ; r. ,, .�. . �.. Rachel Meier, Senior Associate .�+ -'•,,x,;—=� Emma Kaznowski, Research Associate r ,.�.-�- �' '`:�` -`' _ � : - ��� � ;: "� � � � r: ; -a� �F� �.' :► ,.,�. '•,<, < _ , .,,:' .��' _ � — •y : :'� 1 C� L O T U S �► SUSTAINABLE 1 Engineering&Sustainability �DUBUQUE ¢�inble • li¢�nt,lr • rqiufnhl�� ,..% t- THE CITY OF D -- - -.-� : UB E Masterpiece on the Mississippi �' F -..- . .. G HGs a nd CI i mate Cha nge ■ Greenhouse qases (GHGs) create a buffer in Earth's atmosphere. ■ More GHGs in the atmosphere = more trapped heat in the atmosphere. ■ This can lead to increased temperatures, extreme precipitation, flashing flooding, worse air pollution, etc. ■ Decreasing emissions can help mitigate these environmental changes. . . - - � - .. � � • . - �1 � � - " + , � , � ; In-boundary , ur , waste 8 b ary e �`� fores 8 olhcr « ' Y wastewater 8 wastewater ''�I� � land use i1,, 111�.� ��� � . . � _.,► �ss� �• � III � 1 - - - - - -- - - -- � - ------� - � Statanary fuel , . �: combuslbn ,' " � ,� Grid•supplied � ,' e��9Y Transmissior � .� d�str�bution _ � "1 �1 � T� ��� � � �,�, -"� - ��� Industrial � � � i '•�._ ,,,� nda processes 8� � ; houndary -' ry product use transportation �� �ransportation Em ission Sou rces for 2025 Dubuque has been tracking greenhouse gas (GHG) emissions since 2003. Inventories from 2003 to 2018 were completed by volunteers and students at the University of Northern lowa. Lotus completed Dubuque's 2022 inventory as well as the 2025 inventory with the same emission sources. 2025 Sou rces ■ Residential electricity ■ Diesel on-road vehicles orma ion- olar Renewable ■ Residential natural gas ■ On-road electricity nergy Cred� (RECs) ■ Residential propane ■ On-Road T&D losses ■ Residential fugitive emissions ■ Transit ■ Residential transmission and distribution ■ Railways (T&D) losses ■ Aviation ■ Commercial and industrial electricity (C&I) . Waterborne activity ■ C&I natural gas ■ Landfill gas ■ C&I propane ■ Composted waste ■ C&I T&D losses ■ Wastewater ■ Gasoline on-road vehicles ■ Refrigerant leakage Methodology Comparisons : 2022 and 2025 ■ The IPCC's Sixth Assessment Report (AR6) was used for CH4, N20 and R-134a Global Warming Potentials (GWP). In the most recent AR6 update, CH4 was split into CH4-Fossil (27.9 GWP) and CH4-Fugitive (29.8 GWP). ■ Google EIE is undergoing a methodology update, and 2025 vehicle miles traveled (VMT) data will not be available. Lotus used 2025 VMT data from the lowa Department of Transportation (DOT) instead. ■ Lotus separated plug-in hybrid electric vehicle (PHEV) VMT into gasoline VMT and electric VMT per percentage split provided by the Alternative Fuels Data Center. The electric VMT was the only portion subtracted from Dubuque's daily VMT to increase accuracy of VMT attributed to fossil fuels. The 2025 inventory is the first inventory to include renewable energy. Per GPC guidance, this is included as information-only and is not subtracted from Dubuque's overall emissions. ■ Alliant Energy provided Lotus with a T&D loss rate for the 2025 inventory. Previous inventory T&D loss rates were calculated using averages from the US EIA State Electricity Profile for lowa. ■ Lotus included Class A and Class B Motor Homes in on-road emissions based on definitions from lowa's Motor Vehicles and Law of the Road §321 .124. Previous inventories had excluded Class A, B, and C Motor Homes. Class C Motor Homes were still excluded from the 2025 inventory. �,,,���,�„ � Dus f F Emissions by Scope : 2025 . . . _ __ Scope 1 69% - � � � 2025 ,, �,,, , � . 680,236 mt CO2e DUB E .. „ .�+.,. . ::i.i�� Emissions by Sector : 2025 Commercial and Industrial Buildings 44°� 2025 ,, �,,, , � . 680,236 mt CO2e DUB E .. „ .�+.,. . ::i.i�� Emissions by Sector : 2018 and 2025 Commercial and Industrial Buildings 47% 3a Commercial and Industrial Buildings - - 43% - • - • • - . • • - • - 20% 2018 ° 2025 n emissio '�Du�B E 819,408 mt CO2e ween 2 680,236 mt CO2e nd 2 ��.,..,���;�,�. ...� .�L..�.;,,q,� Emissions by Sector : 2022 and 2025 Commercial and Industrial Buildings 43% Commercial and 3 Industrial Buildings . - . 43% • • • • - • - Transportation 30% 2022 ° 2025 n emissio '�DuB E 744, 112 mt CO2e ween 2 680,236 mt CO2e nd 2 ��.,..,���;�,�. ...� .�L..�.;,,q,� Emissions by Source : 2025 Notable Data Points: ■ The largest emission sources • • , . are natural gas (34%), On-Road Transportatlon electricity (29%), and on-road 28" , fossil fuels (29%). . , . _ • - . ■ Solid waste makes up 3% of FugitiveEmissions ,x . . total emissions. Natural Gas . 34% � ,�,.. ■ All other emission sources � � � make up 5% of total • „ �. emissions. , ��„ , � - DuB E V��.frrp�rrron tht.'ttn<�.<qr�r� - ' ti � � � . � • • Dubuque, IA 2025 58,987 680,236 11 .53 Bozeman, MT 2024 56, 114 705,542 12.57 Appleton, WI 2022 74,439 806,790 10.84 Eagan, MN 2022 67,526 919,762 13.62 M i n neton ka, M N 2022 53,529 700,857 13.09 La kevi I le, M N 2022 74,551 520,850 6.99 Eden Prairie, MN 2022 63,623 762,715 11 .99 . -. .- . .. . -. . . � . . . .. . -. � : � Emissions Over Time : Comparable Sources Notable Trends "" ■ Between 2018 and 2025, all �� „� sources decreased except for on- : road gasoline and diesel vehicle . emissions. � • � ��� : ■ Between 2022 and 2025, all . sources decreased except for C&I � natural gas, on-road diesel, and �� ��� . landfill emissions. - ■ Between 2022 and 2025, Alliant's � ��� emission factor decreased 15% due to continued expansion of their renewable energy portfolio. This contributed to the decrease in '" ' '" ' ' ' ' ' ' ' ' ' ' ' ' '"' ' ' " ' '"' ' ' ' ' . . . - . . . . Dubuque's electricity-related . emissions. . . - � : � � �,,,��„�„ Dus f F • • - - • • • - Increase Decrease ■Total �,200,000 39% decrease in emissions since 2003 i,ioo,000 ■ � . � 6 ■�� �,���,��� 6 � ■ � � �6 O � p 9��,0�� 4 a U O N C O U $��,��� � � ■ 7��,0�� 600,000 e�\�el .'Loo� ,2oag .2�,� .2�,, 'L��� �,��� 2�,� .'L�,� .2��6 .2��� .2�,$ Z�`�'� �yo`�-�' �er�l `L�°���ps 2oO� �oO� 2OOg 20,0 �0,, �0,2 20,3 2O,d �0,� �0,6 20,� 2O,$ �022 �°2�`GJt . i � Years Science- Based Target _ Dubuque's science-based �. , emissions reduction target is �' �� '�.� ' '° � 62.4% by 2030. � � `` ' '" � �"`? ■ Lotus used the One Planet Cit Challen e's Y 9 � ..` '' ;...,-'. ' ' ' ,►�%~ "� ' , � _ ,�f; ` (OPCC) approach to calculate Dubuque s � .�: -_- `� science-based target. � . . . . _ . -. , : � . ; . . . l , �=�- - ■ This approach uses the following data points: . : . , . . "� '�4-�. - - ■ US Human Development Index Score (HDI) r � � � �:�l. �-�,��� •► �� ' ' ' l�� � ■ Population projections for Dubuque , � � YL �;. � �� � �. `.� ► �_ j � ' � , , � \' i i ��-+� �"� ` '�� �� -,� �� ■ Baseline year (2018) scope 1 and 2 �.� �` .�T� �V 1 /t•.,'r1 _ .� �'`����,�� ��'-., I , I i �=>t a`�• �' �- .�� ' � � -.�,�..� ,� emissions totals _ ., 7 � e:; � �` " ti ' - �,� �� -_ . � ` � � ' ■ Baseline year (2018) community population .i'�i ' - " . `''" %' ' , 4. �• r ' �+� � � '` �7-�' f-►�.� �w ;�: T �: �-� ,�y ■ Why a Science-Based Target? �'��., ., .- i ,►; �' ;������' . .. : . ;_. . �'1�, �` � " �`. '-- ■ Helps avoid the worst emissions scenario �� . . . l��',__ ,�^.'y�e.��,_ ' ._ ' ' a, , � . � �* '-,�s y• . �' , �`�`��` '� •.:� ■ Ensures the Cit does its art in miti atin �r, . � Y p 9 9 ' climate change impacts �,,,��„�„ Dus f F � � � � � � � � � / 5-Year 2018 2022 2025 2030 2035 2040 2045 2050 Summary Absolute Emissions Target 819,408 734,531 667,590 �308,000 �231 ,000 �154,000 �77,000 0 (mt CO2e) Emissions Reduction Target N/A -10% -20% -62% -72% -81 % -91 % -100% o�a ' - • • . - • . - • • . 1 : • . - . � • . • . • • • - . • • � : � ■ � � � � � � � � / Sector-based % 2022 2025 2030 2035 2040 2045 2050 Reduction Stationary Energy -18% -26% -65% -73% -82% -91 % -100% Transportation 34% 21% -49% -62% -75% -87% -100% Waste and _72% -68% -86% -89% -92% -95% -100% Wastewater IPPU N/A N/A -51 % -60% -71 % -83% -100% (Refrigerants) � _ - - - • • - - . - • : ' � • - - - 1 1 � : . � � � . � � � soo,000 744,112 2022 to 2030:12%decrease �oo,000 657,424 2022 to 2050:38%decrease � soo,000 1 o . 457,648 � 500,000 � N C O � 400,000 .� w � x c� 300,000 200,000 100,000 0 2022 2024 2026 2028 2030 2032 2034 2036 2038 2040 2042 2044 2046 2048 2050 �Electricity Emissions Transmission and Distribution Losses �Natural Gas Emissions Natural Gas Fugitive Emissions �Propane Emissions Stationary Diesel Emissions �Total On-Road Gasoline,Diesel,and Ethanol Emissions Electric Vehicle Emissions Electric Vehicle Emissions(T&D) Waterborne Emissions Transit Biodiesel Emissions Transit Diesel Emissions Transit Ethanol Emissions �Transit Gasohol Emissions Railway Emissions Local Aviation Emissions �Itinerant Aviation Emissions �Landfilled Waste Emissions Compost Emissions Wastewater Emissions �Commercial Refrigerant Loss Emissions RPsidPntial RPfriqPrant loss Fmissions —Total Fmissions . i � . What is Dubuque Doing ? ■ Current Projects: _ • Energy Savers Program ,��/�.:�'�-- ^— / ,�. • Provided high efficiency furnaces and/or :�� "' � � water heaters to low-income residents who i'j►�"��" � had appliances that were 10+ years old/in , _ disrepair. � - - ` ���� • Youth Climate Action Fund '���� �- _ ` -�=�'�_�= � I�' �" -=y_ -- . _ � t . - - _ Awarded 19 microgrants to Dubuque youth " _ (15-25 yrs) and Youth Serving CBOs to '' " � _ '" ,,.� - ���. � .; - partake in climate action-$85,000! - _ �-- G _ "%��-��'.-��' _ __ i • Direct Pay Provision � �- � � �_ ,� �' -- ,�� - ,����' � ,� -�,;_ �� .�� ,��,;. _-- ,� _ - • $427,000 for the City from the airport solar c��y .,.4�'�+ �",,.:� �, :�-��, , ,�--� array and EV chargers. �.� "- = i''�����,� � -�- , � „ -�,,;, � - �� _- � . � - �� -� � � � � � 'r-� � '� - � Branching Out Dubuque Initiative: �—�--- .�--- r � � ._ _--� � �' ��� + . � Tree planting around Dubuque with a goal of 5,280 trees! , y � . . _ . _b. �� �,,,��„�„ Dus f E �,!.� „��,., , , �.r., ;., '.•- , � .. Loo ki n g Fo rwa rd - � � - �.-----� -� �. -- - �:- - - - - - r - .h' • '�. }� -,.,,. 'n: -��� -�-af.., •1.- '�: �, ,, �;a .. _ . - _ � -,►�:i_ �`� l� • . � � ^� _ '�. ..y "Y ' _ . ' ^i1 '� �. � . ' •�w• ��+n4�' .._�► ■ Future Projects: � � � � • 2 municipal solar energy projects r • Currently working on feasibility study � ����� -� �\'_- • Climate Action Plan update ��� ��., - � ; � � • Internal update of Dubuque's 50% reduction goal by 2030 to - �� � ' ' -. r h wi r i n � � eac a de aud e ce. ' �� .. • Energy Savers Program second round ., -_`��� - �. ■ Think long-term � • Invest in climate-friendly infrastructure and public transit. • Incremental efforts. • Outreach & education. - - • Sustainable funding sources. ■ Long-term benefits _ • Social cost of carbon � � t.�'�'� -. _ ,,.,�,�,,: � • Natural disaster mitigation :�•_ ,' -� � • Cost savings . . , ' 1�'� :,�j��„ �:�:,: , � ��}' �� � . � ,�• .��;,:. ;� �, • Resilience � : ,� �� '{ �, �. • . i�. �•�� !��;: �,��; �,,,�i,�. � � ..i . � �• � . '4+ � �� w*4�!` . 4�C � •v .�� . . nnun„i �� • � •, 1• Dus E .� . ; .., �, , � � �,� �� � " . fl`3tT'A I N A,B L E .1L�,trm�t�,,n N�r\ti•,n.;j,��: I . � . � � .1r_ . . �`{ . .1�,�4� � " - �nr n ' . :3�.�-. ,.�'�f� ���Lr .` �'��� !l' ' r'�19t/� /�l� � - � � "♦ �1►.� �L . " }. , �:. .�p�,� ., 4�^ �Qµ • � -��`"-' .�'�� � � .. . _,� �t, if • •. i �• , , / 1 . , , � � �, � � •• � - • R _ • .. •,#f _�� • � : � � � � , at ; ,� . � � �� , • • . . ; , - - � .- � - �` - � ~ . - � � - �-:� ;;-� - .�,y , � ! -' � . �_ •.r�'.;y;y'�,��•�..�. �v� _ `,,'•,..`�'4.:'C- �'�.- . .`!�j�1±',``r � v . :e ` Q T V rachel@lotussustainability.co � , �neer�ng & S�Stp�npb���. emma@lotussustainabilit ,�„ , , DUB � SUSTAINABLE ,�- '.�- . • •.