San Francisco Public Utilities Commission’s CleanPowerSF Signs Battery Storage Contract

by Paul Ciampoli
APPA News Director
August 31, 2023

The San Francisco Public Utilities Commission’s community choice energy program, CleanPowerSF, has signed a 15-year battery storage contract with the Corby project, a subsidiary of NextEra Energy Resources, LLC.

The new facility is CleanPowerSF’s first standalone battery storage project located in Northern California.

Expected to be operational in 2025, the Corby project will have a total capacity of 300 MW of battery storage located in Solano County.

Specifically, the project will be able to store up to four hours of energy produced in the middle of the day “when solar is abundant and electricity is at its cheapest and discharge that electricity when it may be in short supply and costlier to produce, such as in the early evening,” the San Francisco PUC said.

“In California, we are experiencing weather whiplash — rapid swings of extreme weather caused by climate change,” said SFPUC general manager Dennis Herrera. “Whether it be prolonged drought, unprecedented rain, or seasonal wildfires, we’re focused on ensuring that our services are reliable and available. That’s why the Corby project is critical. We’re adding more clean energy to the grid and battery projects like Corby will improve reliability for our customers and people across California as we face an evolving future.”

The project will create up to 200 construction jobs and generate approximately $40 million in local tax revenue over the life of the project.

In addition, through the SFPUC’s Social Impact Partnership Program, NextEra Energy Resources has also committed to investing in education and workforce development initiatives in Solano County and beyond.

In addition to the Corby project, CleanPowerSF has also committed to sourcing energy from another NextEra Energy Resources subsidiary called Paulsell Solar Energy Center in Stanislaus County.

The solar photovoltaic power facility, which broke ground in August 2022 and is expected to be operational in June 2024, will generate up to 20 MW of renewable solar energy and 15 MW of battery energy storage.

To date, CleanPowerSF has contracted 467 MW of new wind and solar projects in California and signed four solar plus battery storage contracts.

In April 2021, San Francisco Mayor London Breed announced that CleanPowerSF will provide all customers 100% renewable electricity by 2025, five years ahead of the city’s original goal of 2030 and 20 years ahead of the state’s goal of 2045.

Along with CleanPowerSF, the SFPUC operates Hetch Hetchy Power, which provides 100% greenhouse gas-free energy to public facilities such as City Hall, schools and libraries, some private commercial developments, and affordable housing. Collectively, the two programs serve over 70% of the electricity consumed in San Francisco.

The San Francisco Public Utilities Commission is a department of the City and County of San Francisco. It delivers drinking water to 2.7 million people in the Bay Area, collects and treats wastewater for the City and County of San Francisco, and meets over 70% of the electricity demand in San Francisco.