CleanPowerSF is a program of the San Francisco Public Utilities Commission (SFPUC), an enterprise department of the City and County of San Francisco.
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eanPowerSF is committed to protecting customer privacy. Learn more at cleanpowersf.org/privacy .
OUR MISSION: To provide our customers with high-quality, efficient and reliable water, power and sewer services in a manner that values environmental and community interests and sustains the resources entrusted to our care.
525 Golden Gate Ave., 7th Floor
San Francisco, CA 94102
T (415) 554.0773
TTY (415) 554.3488
[email protected]
Dat
e:
To:
Thr
ough:
May 27, 2026
Commissioner Joshua Arce, President
Commissioner Stephen Leveroni, Vice President
Commissioner Avni Jamdar
Commissioner Kate H. Stacy
Commissioner Meghan Thurlow
Dennis J. Her rera , General Manager
Barbara Hale, Assistant General Manager, Power
Mi
chael Hyams, Deputy AGM, CleanPowerSF and Power Resources Grace Kay, Acting Deputy AGM, Programs and Services
From
: Sandra Hamlat, CleanPowerSF Operations
Colten Krieg, CleanPowerSF Operations
Dan Willis, Power Regulatory and Legislative Affairs
Subj
ect: Annual Report to the California Energy Commission by Hetch Hetchy Power and CleanPowerSF on their Sources of Electric Energy and Greenhouse Gas Intensity
Summary
Hetch Hetchy Power and CleanPowerSF recently submitted their respective Power Source Disclosure Reports for calendar year 2025 to the California Energy Commission (CEC) as required by statute by June 1, 2026.1 The Power Source Disclosure Report shows the sources of energy used to meet electric demands as well as the greenhouse gas intensity of each retail electricity product. All California retail providers of electric energy are required to use a consistent method to calculate the greenhouse gas intensities of their products.
This memo summarizes the data reports that were provided to the California Energy Commission.
1 California Public Utilities Code Sections 398.4 and 398.5.
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Hetch Hetchy Power
Hetch Hetchy Power offers two electricity supply products that must be included in its Power Source Disclosure Report: (1) Hetch Hetchy Power and (2) Hetch Hetchy Premium.
(1) Hetch Hetchy Power
For calendar year 2025 , Hetch Hetchy Power’s energy mix was 100 percent greenhouse gas ( GHG)-free hydroelectric generation. Hetch Hetchy Power generation came from the Holm, Moccasin, and Ki rkwood hydroelectric power plants, meeting 99 percent of customer needs , with the remaining 1 percent consisting of GHG-free hydroelectric power delivered by the Western Area Power Administration to serve Treasure and Yerba Buena Islands . The GHG emissions intensity of Hetch Hetchy Power was 0 pounds of carbon dioxide equivalents per megawatt-hour (CO2e/MWh).
Hetch Hetchy Power also generated Renewable Portfolio Standard- eligible electricity above its retail needs from in- city solar installations, biomass energy from the Southeast Cogeneration Plant, and from the Kirkwood hydroelectric facility. This surplus generation, totaling about 190,000 MWh, was sold into the wholesale energy market with Hetch Hetchy Power retaining the associated renewable energy credits. These credits can be used to meet Hetch Hetchy Power’s Renewable Portfolio Standard obligations in future years, if needed.
(2) Hetch Hetchy Premium
For calendar year 2025, Hetch Hetchy Premium’s energy mix w as 100 percent GHG-free hydroelectric generation and met the requirements of the California Air Resources Board’s Low Carbon Fuel Standard Program
. Hetch Hetchy
Premium generation came from the Kirkwood hydroelectric power plant. The GHG emissions intensity of Hetch Hetchy Premium was 0 pounds of CO2e /MWh.
This Premium service allows the San Francisco Municipal Transportation Agency, the San Francisco International Airport, and the Port of San Francisco to receive additional credits under the California Air Resources Board’s Low Carbon Fuel Standard Program . This program rewards these entities for using clean electric energy instead of fossil fuels for transportation-related uses.
CleanPowerSF
The San Francisco Climate Action Plan 2026 guides the SFPUC to continue providing San Franciscans 100 percent renewable and/or GHG -free electricity supply. CleanPowerSF first achieved this milestone in 2023 for all customers by delivering an electricity mix composed of 63 percent Renewables Portfolio Standard (RPS) -eligible electricity and 37 percent GHG -free hydroelectric Page | 3
power across its three products. In 2025, CleanPowerSF again supplied customers with 100 percent renewable electricity mix – consisting of 87 percent RPS-eligible and 1 3 percent GHG-free hydroelectric energy for all customers across its three products.
The power content of CleanPowerSF’s three electricity supply products – (1) Green; (2) SuperGreen; and (3) SuperGreen Saver – must be included in its Power Source Disclosure Report. The power content of each of them is summarized below.
(1) Green
For calendar year 2025, CleanPowerSF’s Green product energy mix was:
• 84 percent CA Renewables Portfolio Standard Energy Resources ,2 including:
o 42 percent Solar
o 18 percent Geothermal
o 19 percent Wind
o 3 percent Biomass and Biogas
o 1 percent Eligible Hydroelectric; and
• 16 percent GHG-free hydroelectric generation.
Staff estimates the Green product’s GHG intensity was approximately 3 pounds of CO2e/MWh of electricity delivered. By comparison, the statewide average for California in 2024 (latest available data) was approximately 359 pounds of CO2e/MWh.3
(2) SuperGreen
For calendar year 2025, CleanPowerSF’s SuperGreen product energy mix was 100 percent C alifornia Renewables Portfolio Standard- eligible resources, including:
o 50 percent Solar; and
o 50 percent Wind.
All SuperGreen generation came from new renewable energy facilities built in California that first reached commercial operation since CleanPowerSF began
2 Due to the Senate Bill 1158 (Becker, 2022) rulemaking, the CEC updated the Power Content Label template to display percentages rounded to the nearest whole number. As a result, the total shows a 1 percent discrepancy, with all values rounding to a combined total of 84 percent. 3 This number, compiled and published by the CEC, is an average of all load serving entities across California in 2024. This figure was included on the 2024 Power Content Label sent to customers by October 1, 2025. The Power Content Label allows customers to easily compare the resource breakdown and emissions intensity of their electricity product with the State’s as a whole.
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serving customers in 2016. The GHG emissions intensity of the SuperGreen product was 0 pounds of CO2e/MWh.
(3) SuperGreen Saver
SuperGreen Saver is a product available for eligible CleanPowerSF low- income customers4 who live in select disadvantaged communities ( DACs) in San Francisco. CleanPowerSF’s service territory includes 17 disadvantaged community census tracts.5
Figure 1. Disadvantaged Community Census Tracts
*Customers living in the census tract on Treasure Island are entirely served by Hetch Hetchy Power, San Francisco’s municipal electric utility, and are, therefore, not part of CleanPowerSF’s service territory.
Image from CalEPA, accessed April 13, 2026.
< https://oehha.ca.gov/calenviroscreen/sb535 >
For calendar year 2025, CleanPowerSF’s SuperGreen Saver energy mix was 100 percent C alifornia Renewables Portfolio Standard- eligible resources, including:
o 100 percent Solar.
The GHG emissions intensity of the SuperGreen Saver product was 0 pounds of CO2/MWh.
4 Low-income eligible customers must be eligible for and enrolled in either the California Alternate Rates for Energy (CARE) Program or Family Electric Rate Assistance Program (FERA). These programs provide monthly discounts on energy for income-qualified customers. 5 Disadvantaged communities are determined as such by the California Communities Environmental Health Screening Tool, developed by the California Environmental Protection Agency’s Office of Environmental Health Hazard Assessment. Commonly known as CalEnviroScreen, the tool identifies the top 25 percent of the communities in California with the highest disproportionate pollution burden, and the CPUC designates DACs in the top 25 percent of pollution burden from the CalEnviroScreen versions 3.0 and 4.0.
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NEXT STEPS
Attestation of Veracity to be completed in September
After Hetch Hetchy Power, CleanPowerSF and other retail sellers of electricity submit their Power Source Disclosure Reports, the CEC will compile the reports and calculate the statewide average GHG emissions intensity and use of energy resources by type. The CEC will then develop the Hetch Hetchy Power and CleanPowerSF Power Content Labels that compare the results summarized here against the statewide average in 2025. Power Enterprise staff will post the Power Content Label for each program on the SFPUC’s website. The CEC requires this to occur by October 1. Power Enterprise staff will also provide the Power Content Labels to our customers by postal mail or email by the end of the December billing cycle.
CEC regulations require that the SFPUC Commission attests to the veracity of both Power Source Disclosure Reports by October 1 of each calendar year. As the Power Content Label is not available before the June 1, 2026, Power Source Disclosure Report submission date, staff are providing this memo to inform the Commission and the public of the sources of power for our two programs for calendar year 2025. Staff will bring two resolutions for the Commission’s approval that will attest to the veracity of the Hetch Hetchy Power and CleanPowerSF Power Source Disclosure Reports to a September 2026 Commission meeting.