Authors 2019 Community Strategy Analysis
License CC-BY-NC-ND-4.0
GHG Emissions,
Forecast, and Wedge
Analysis for City of
Golden, CO
2019 Community Strategy
Analysis
April, 2022
Produced by ICLEI - Local Governments for Sustainability USA
Table of Contents
City of Golden’s Greenhouse Gas Inventory 3
2019 Annual GHG Emissions 4
Stationary Energy 6
Transportation 8
Solid Waste 9
Water & Wastewater 9
Fugitive Emissions 9
Data Gaps 10
City of Golden’s Greenhouse Gas Forecast & Planning Scenarios 10
Business as Usual Forecast 10
Planning Scenarios for Emissions Reductions 13
Modeling Results 17
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USA.
Golden, CO 2019 Community Strategy Analysis Page 2
City of Golden’s Greenhouse Gas Inventory
The City of Golden first
developed a Greenhouse Gas
(GHG) Inventory in 2010 for
the 2007 activity year (Figure
1). The 2007 GHG inventory
was conducted using methods
developed by Dr. Anu
Ramaswami. The method used
the standardized Local
Governments Operations
Protocol (LGOP) developed by
ICLEI (ICLEI v.1 September
2008) to report GHG emissions
from in‐boundary (within
jurisdictional boundary)
activities. That protocol was
later updated as the US
Community Protocol and
provides a protocol for
quantifying and reporting GHG
emissions for communities.
Figure 1 The City of Golden first developed a Greenhouse Gas Inventory in 2010 for the 2007
activity year.
Local governments estimate and report on community GHG fluxes using a tool known as a GHG
inventory. A GHG inventory estimates the quantity of GHG emissions and removals associated with
community sources and activities taking place during a chosen analysis year. By conducting additional
inventories, and presenting data over time, local governments can use community GHG inventory
reports to provide information on trends in GHG emissions associated with a given community. Local
governments may choose to develop a community GHG inventory report for several reasons, including
to:
● Inform climate action planning
● Demonstrate accountability and leadership
● Track GHG emissions performance over time
● Motivate community action
● Recognize GHG emissions performance relative to similar communities
Golden, CO 2019 Community Strategy Analysis Page 3
● Enable aggregation of GHG emissions data across regions, and
● Demonstrate compliance with regulations, voluntary agreements, and market standards (where
applicable).
Community GHG inventory reports typically focus on selected GHG emissions occurring within
the jurisdictional boundary of the community (e.g., emissions from combustion of natural gas in
furnaces throughout the community), as well as certain trans-boundary emission sources
associated with community activities (e.g., emissions from electricity generation at a power plant
located outside the community associated with electricity use occurring in the community).
GHG emissions are typically categorized according to the related activity or source. While the US
Community Protocol uses activity and source to distinguish emissions, the Global Protocol for
Community GHG Inventories uses Scope, similar to a corporation or local government operations GHG
inventory. Other reporting entities such as the Global Covenant of Mayor use Direct and Indirect to
classify emissions. This memo will use the terms Scope 1, 2, and 3.
2019 Annual GHG Emissions
Using the US Community Protocol, 2019 data on sources and activities for Golden were collected and
entered into ICLEI’s ClearPath online Climate Action Planning Tool. Below is the breakdown of
emissions by the sector and the fuel or source (Table 1 and Figure 2). This 2019 version of Golden’s
GHG Inventory focuses on Scope 1 & 2 emissions as those emissions are most likely to be under the
control or influence of Golden. Related to this inventory, Solid Waste and Water/Wastewater are both
emissions that occur outside the boundary of Golden but are the result of activity taking place within
Golden. The collection and understanding of Scope 3 emissions can be an important community
consideration as they represent goods and services that are demanded by the community, but whose
emissions are actually Scope 1 & 2 of another community. Tracking Scope 3 emissions in essence
allows a community to have an understanding of those emissions without double counting. However,
for the purposes of this Inventory and its use to build emissions reduction strategies, ICLEI has
provided a 2019 Inventory that contains the primary emitting sectors related to community activities.
Golden, CO 2019 Community Strategy Analysis Page 4
Table 1 Breakdown of Emissions by Scope and Sector as defined by the US Community Protocol and GPC.
Scope Sector Emissions (MT-CO2e)
Transportation & Mobile Sources 129,262
Commercial Energy 69,855
Scope 1 Residential Energy 25,342
Process & Fugitive Emissions 2,420
Total 226,879
Commercial Energy 118,369
Scope 2 Residential Energy 26,172
Total 144,541
Solid Waste 6,686
Scope 3 Water & Wastewater 3,587
Total 10,273
Golden 2019 GHG Emissions (mtCO2e)
3,586 ,
6,686 , 2% 2,421 , 1%
1%
51,516, 13%
129,263 , 34%
188,226, 49%
Residential Energy Total Commercial Energy Total
Transportation & Mobile Sources Total Solid Waste Total
Water & Wastewater Total Process & Fugitive Emissions Total
Figure 2 Additional breakdown of emissions based on Sector Only.
Golden, CO 2019 Community Strategy Analysis Page 5
Table 2 A breakdown of emissions by Sector and fuel source.
Emissions
Sector Fuel or Source Usage Units (CO2e)
Electricity 50,572,914 kWh 26,173
LPG* 3726 MMBtu 237
Residential Energy
Natural Gas 4,699,255 Therms 24,994
Kerosene* 1480 MMBtu 112
Residential Energy Total 51,516
Electricity☨ 228,720,987 kWh 118,370
Commercial Energy
Natural Gas 13,134,090 Therms 69,856
Commercial Energy Total 188,226
Diesel 14143189 VMT 22,093
Transportation & Mobile Sources Gasoline 210742287 VMT 98,142
Other 9,028
Transportation & Mobile Sources Total 129,263
Waste Sent to
Solid Waste Landfill 19078 Tons 6,600
Other 86
Solid Waste Total 6,686
Wastewater
Water & Wastewater Energy 3,314
Fugitive Emissions 274
Water & Wastewater Total 3,586
Process & Fugitive Emissions Total 2,421
*Estimated emissions based on Census estimates of homes using fuel Total
381,698
source and the average MMBtu based on Natural Gas Consumption. Emissions
☨Includes a small amount of Streetlight Energy Consumption
Stationary Energy
The majority of Golden’s emissions come from stationary commercial/industrial energy (49.3%) and
residential (13.5 %) energy sectors as evident from the emissions from stationary fuel (natural gas for
heating and process energy) and electricity. Data for this sector comes from Xcel Energy’s Community
Energy Report1. Xcel Energy provides communities in its service territory with annual updates,
providing consumption of electricity and natural gas by residential and commercial sectors. Xcel
Energy also provides a utility-specific emissions factor for its Colorado Service Territory. In 2019, the
emissions factor reported by Xcel energy was 0.514 metric tons of CO2/MWh. Xcel does not provide an
emissions factor for CH₄ and N₂O, therefore EPA’s eGRID data set for the Rocky Mountain West (WECC
Rockies RMPA)2
1 Xcel Energy Community Energy Reports Updated September 15, 2021
2 EPA Egrid 2019 Accessed August 1, 2021.
Golden, CO 2019 Community Strategy Analysis Page 6
Table 3 2019 Energy Consumption Data provided by Xcel Energy.
Carbon Emissions (metric
Electricity Number of Customers [5] Energy Consumption (kWh)
tons CO2) [6]
Business3 1,653 228,257,166 117,324
Residential 8,317 50,572,914 25,994
Street Lighting - Metered n/a 9,731 5
Street Lighting - Non-Metered/Customer n/a 16,095 8
Owned
Street Lighting - Non-Metered/Xcel-Owned n/a 437,995 225
Total: 9,970 279,293,901 143,557
Energy Consumption Carbon Emissions (metric
Natural Gas Number of Customers [5]
(therms) tons CO2) [9]
Business³ 1,202 13,134,090 69,611
Residential 6,071 4,699,255 24,906
Total: 7,273 17,833,345 94,517
Subsequent to the completion and analysis of Golden’s 2019 GHG Inventory, an updated Community
Energy Report was provided by Xcel Energy. In an effort to provide a more complete inventory and
analysis, 1 entity that was excluded from the original dataset provided permission to have their data
included in the updated Community Energy Report. However, there are still 2 Natural Gas accounts
removed from the dataset to meet Regulatory Privacy Requirements. This regulatory requirement is
referred to as the “15x15 Rule.” The 15x15 rule is applied to data that is provided by the utility and will
remove an entire data set if there are not at least 15 individual records. The utility will also not include
any individual data point if it represents more than 15% of the total data set. Attempts to identify
commensurate data such as economic or wholesale data were not viable as those datasets also had
redacted data due to confidentiality. As a result, these data are not included in the inventory, nor the
BAU forecast and emissions reduction analysis. It should also be noted that Xcel’s update Community
Energy Report also include changes to total customers and residential consumption. These data were
also updated subsequent to the initial analysis.
Data for this sector comes from Xcel Energy’s Community Energy Report4. Xcel Energy provides
communities in its service territory with annual updates, providing consumption of electricity and
natural gas by residential and commercial sectors. Xcel Energy also provides a utility-specific emissions
factor for its Colorado Service Territory. In 2019, the emissions factor reported by Xcel energy was
0.514 metric tons of CO2/MWh. Xcel does not provide an emissions factor for CH₄ and N₂O, therefore
EPA’s eGRID data set for the Rocky Mountain West (WECC Rockies RMPA)5
3 To protect individual customer confidentiality, Xcel Energy applies the "15/15 rule" as an aggregation standard to the energy consumption
section of this report. So long as a given aggregated value contains 15 or more customers and no single customer makes up 15 percent or
more of the aggregated value, the value can be publicized in this report. If these conditions are not met, customers will be removed. The
number of customers removed is presented for informational purposes.
4 Xcel Energy Community Energy Reports Updated March 2022
5 EPA Egrid 2019 Accessed August 1, 2021.
Golden, CO 2019 Community Strategy Analysis Page 7
Transportation
The second-largest contributor to community-wide emissions is transportation (33.8%). Utilizing the
Denver Regional Council of Governments6 (DRCOG) modeled VMT for Golden (Table 5) and the
Colorado Department of Public Health & Environment estimate of on-road vehicle mix (Table 6) for
Golden, the estimated emissions from on road vehicles are 120,235 mt-CO2e. There were smaller
transportation emissions from off-road sources7 (EPA 2017 National Emissions Inventory) and the
railroad8 within Golden of 9,028 mt-CO2e.
Table 5 VMT Breakdown.
2015 Grand Total Est. 2018 Grand Total Est. 2019 Grand Total Est.
Golden DVMT 677,913 652,784 665,348
Golden VMT (annual) 229,134,543 220,640,894 224,887,725
Table 6 Fleet Mix.
Passenger Light Heavy Motorcycles
Percent of all Gas 41.01% 49.80% 2.33% 0.57%
VMT Diesel 0.04% 0.18% 6.07% 0.00%
Solid Waste
Emissions from waste generated within Golden used waste generation/household counts 9/ census
average persons per household10 to develop a baseline of waste generation per person in order to
calculate total residential waste generation. Non-residential waste was estimated using Golden Job
counts11, EPA's average waste generation per person per day12 and average workdays to develop an
estimate.
Water & Wastewater
Activity data for the Wastewater Sector was provided by Metro Wastewater Reclamation District 13 and
the Molson Coors Wastewater Treatment Plant14. Fugitive emissions were calculated based on the
6 DRCOG uses an Origin-Destination model to calculate DVMT for each jurisdiction within the region
7 EPA NEI- Off-road emissions were downscaled from Jefferson County data using on a population-based allocation
8 Emissions are specific to Golden and calculated using an Eastern Regional Technical
Advisory Committee (ERTAC) confidential dataset.
9 Census Demographic And Housing Estimates
10 Colorado Census QuickFacts- Colorado persons per household was used because it more closely aligned with provided data.
11 Census OnTheMap Job Counts - 2018 job counts were used because 2019 data was not available at the time of inventory development
12 EPA Waste National Overview
13 Wastewater treatment and energy was downscaled from a MWRD territory dataset using a population-based allocation. MWRD service
population includes accounts from West Pleasant View, as separate data would be negligible.
14 Treatment service population was estimated using customer accounts and average persons per household
Golden, CO 2019 Community Strategy Analysis Page 8
population served by each Treatment facility. Any combustion of digester gas at the facilities was
allocated based on the population of Golden compared to the total population served by each facility.
Fugitive Emissions
Fugitive Emissions were calculated using an estimate of leakage occurring within the Natural Gas
Distribution lines within the Boundary of Golden. A leakage rate of 0.3% was applied to the total
Natural Gas Consumed. This does not include any leakage from the upstream extraction and
distribution of Natural Gas.
Golden, CO 2019 Community Strategy Analysis Page 9
Data Gaps
Table 7 Inventory Data Gaps
Stationary Energy Sectors 2 Large Natural Gas Commercial Customers (due
to the 15/15 rule and/or outside boundary of
Golden) .
Transportation Attributable aviation emissions from Denver
International Airport could not be determined
because there were no current datasets.
Solid Waste Provided community-wide waste generation data
represented roughly 65% of residential
generation and no non-residential generation
(estimates were made to represent missing
data).
City of Golden’s Greenhouse Gas Forecast &
Planning Scenarios
Business as Usual Forecast
ICLEI utilized the ClearPath Climate Action Planning Tool to develop a Business as Usual (BAU) Forecast
for Golden through 2030 and 2050. Using population growth as a driver for additional energy
consumption, ICLEI modeled an annual 1% growth in the sectors of residential, commercial, and
transportation sectors. This 1% growth was also used to determine growth in sectors that contribute to
emissions such as Solid Waste, Water/Wastewater and Fugitive Emissions. In addition, Xcel Energy
has received approval for its Colorado Energy Plan which would reduce emissions by 80% from 2005
levels by 2030. This carbon intensity of the electricity sector was also modeled as part of the BAU
forecast as there was a formal approval of the plan by the Public Utilities Commission.
Golden, CO 2019 Community Strategy Analysis Page 10
Figure 3 Timescale graph of emissions along with a 50% emissions reduction goal (Red dotted line) and a Science Base Target (Green
dotted line) that is in line with the IPCC recommended reductions to stay below 1.5 degrees Celsius.
Golden, CO 2019 Community Strategy Analysis Page 11
To better analyze emissions reductions, detailed outputs of each sector by 2030 are presented below.
Table 8 shows a BAU forecast with Golden’s existing 2018 IECC Building Code, Xcel Energy’s approved
decarbonization plan, on-road vehicle fuel efficiencies from the Federal CAFE standards, and projected
BAU Electric Vehicle adoption. Table 9 is the same BAU projection along with additional modeling of a
100% renewable electricity achievement by the City of Golden.
Table 8 Numerical outputs of a 2030 BAU projection with known electricity decarbonization, existing 2018 IECC building codes, projected
on-road fuel efficiencies, flat VMT and BAU Electric Vehicle adoption.
2030 Business as Usual
Assumptions: 2018 IECC Building Code, Xcel Energy Emissions Factor 80% of 2005, No reduction in VMT and BAU EV
adoption
Process &
Commercial Residential Transportation & Water & Fugitive
Energy Energy Mobile Sources Solid Waste Wastewater Emissions
Emissions
(CO2e [MT]) 121,450 37,506 114,981 7,383 1,524 2,701
Table 9 Numerical outputs of a 2030 BAU projection with 100% Renewable Electricity, existing 2018 IECC building codes, projected on-
road fuel efficiencies, flat VMT and BAU Electric Vehicle adoption .
2030 Business as Usual
Assumptions: Same as above, plus additional Golden specific renewables to achieve 100%
Transportation Process &
Commercial Residential & Mobile Water & Fugitive
Energy Energy Sources Solid Waste Wastewater Emissions
Emissions
(CO2e [MT]) 77,937 27,885 114,981 7,383 306 2,701
Even with planned lower carbon electricity from Xcel Energy and realization of 100% Renewable
Energy, stationary fuels will remain a large contributor to Golden’s overall emissions footprint. Natural
Gas used in the thermal heating of water and spaces will continue to produce CO2 emissions.
Transportation emissions stay relatively flat as growth in VMT is somewhat blunted by fuel efficiency
standards in new cars as well as Electric Vehicle sales growth in line with current projections.
Golden, CO 2019 Community Strategy Analysis Page 12
Planning Scenarios for Emissions Reductions
In 2019, Golden City Council unanimously passed Resolution 2656 to formally revise Golden’s existing
sustainability goals and set new targets related to energy, water and waste. Related to this inventory
and energy, Golden intends to meet the following Sustainability Goals:
● Renewables. To achieve 100% renewable energy for electricity by 2030 and 100% renewable
for heating by 2050. To align Greenhouse Gas Emissions reductions with the Paris Accord by
2050.
● Efficiency. To reduce consumption of electricity by 15% by 2030 and reduce consumption of
natural gas by 15% by 2030.
● Transportation. To achieve 20% fossil fuel-free transportation sector by 2030 and 100% fossil
fuel-free transportation sector by 2050.
This Planning analysis also considers the following strategies that were identified by the Community
Sustainability Advisory Board and Golden Sustainability staff:
● Large scale community solar project and/or full buildout of distributed generation on existing
buildings. (15 MW)
● Electrifying transportation through Electric Vehicle Adoption and expansion and enhancement
of RTD’s light rail line.
● Net zero buildings.
● Building Electrification
● Building Efficiency
The calculated emissions from the above high level strategies15 are modeled below and presented by
sector. ICLEI ran two separate scenarios of renewable electricity. The first scenario modeled includes
a 100% decarbonized grid with the remaining strategies. The second scenario attempts to model a
middle ground where Golden continues to pursue renewable options. With Xcel’s planned and
approved decarbonization plans16, the remaining gap to achieve 100% Renewable Electricity would
need to be met with interconnected solar where the RECs remain with the City of Golden, its residents,
or commercial building owners. Therefore, a 15 MW solar expansion project is modeled on top of
Xcel’s Colorado Energy Plan. This 15 MW is divided equally between residential and commercial solar.
This 15 MW could likely be met with utility scale renewable projects where the RECs are retired on
behalf of the subscriber.
15 During discussion with Golden City Staff and the Community Sustainability Advisory Board, it was determined to not model the 15%
reduction in electricity consumption. As buildings and vehicles are increasingly electrified, the added consumption of cleaner electricity would
make it virtually impossible to meet that goal.
16 During the drafting of this report, Xcel Energy announced it would likely reach an 85% reduction in Carbon Intensity from its 2005 levels.
This analysis still represents the approved plan and anticipated 80% reduction.
Golden, CO 2019 Community Strategy Analysis Page 13
Figure 4 Projected 2030 emissions by sector (Scenario 1).
Table 10 Projected 2030 emissions by sector (Scenario 1).
2030 Emissions by Sector (Scenario 1)
Commercial Residential Transportation & Solid Waste Water & Wastewater Process &
Energy Energy Mobile Sources (MT CO2e) (MT CO2e) Fugitive
(MT CO2e) (MT CO2e) (MT CO2e) Emissions
(MT CO2e)
62,970 20,215 93,909 7,383 306 2,701
Golden, CO 2019 Community Strategy Analysis Page 14
Figure 5 Projected 2030 emissions by sector (Scenario 2).
Table 11 Projected 2030 emissions by sector (Scenario 2).
2030 Emissions by Sector (Scenario 2)
Commercial Residential Transportation & Solid Waste Water & Wastewater Process &
Energy Energy Mobile Sources (MT CO2e) (MT CO2e) Fugitive
(MT CO2e) (MT CO2e) (MT CO2e) Emissions
(MT CO2e)
102,189 29,532 96,892 7,383 1,524 2,701
Golden, CO 2019 Community Strategy Analysis Page 15
(In Production)
Figure 6 Wedge depiction of emissions reductions with all strategies, Xcel's known decarbonization, and an additional 15 MW of Solar.
FIgure 7 Depiction of emissions reductions in the year 2030 by action (Scenario 2).
Modeling Results
Table 12 Scenario Modeling Results.
Scenario Results
2030 Business-As- 2030 Emissions Percent Reduction
Usual Emissions (After actions)
Scenario 1 231,698 187,477 50.9%
Scenario 2 285,544 240,219 37.1%
Golden, CO 2019 Community Strategy Analysis Page 16