Del Mar and Solana Beach's power provider just committed to a 25-year energy storage contract, and it won't owe a cent on the deal until the facility begins operating in 2031.
The Clean Energy Alliance board approved the agreement with GEM A-CAES LLC on Thursday, July 30, according to the San Diego Union-Tribune. The deal secures 60 megawatts of capacity from the Willow Rock Energy Storage Center, a compressed-air facility under construction near Rosamond in Kern County.
CEA serves more than 255,000 customer accounts across seven North San Diego County cities, including Del Mar and Solana Beach, where it has been the default power provider since May 2021. The nonprofit joint powers authority was founded by those two cities and Carlsbad in 2019.
What the facility does
Willow Rock uses Advanced Compressed Air Energy Storage technology developed by Hydrostor, a Canadian company and GEM A-CAES's parent. The system compresses air into underground hard-rock caverns roughly 2,000 feet below the surface. When electricity demand spikes, the air is released through turbines to generate power with no fossil fuel combustion, according to a U.S. Department of Energy description of the project.
The full Willow Rock facility is designed to store 4,000 megawatt-hours and deliver 500 MW for more than eight hours. CEA's share is 60 MW of that total capacity.
Why the state required it
The California Public Utilities Commission mandates that community choice energy programs like CEA procure additional long-duration storage as older fossil-fuel plants retire. CEA's board agenda report stated the agency's existing solar-plus-storage contracts are expected to satisfy its share of a broader 4,500 MW procurement requirement, but the Willow Rock deal addresses a separate 1,500 MW long-duration storage mandate.
CEA CEO Greg Wade said in an Aug. 6 Hydrostor press release that the facility "will play a vital role in helping CEA meet both state reliability mandates and our customers' growing energy needs with clean, dependable capacity."
How CEA picked the developer
CEA issued a solicitation in March 2025 and received responses from 25 developers. Proposals were evaluated on technology type, price, development risk, location and environmental and social benefits, according to the Union-Tribune's reporting.
The contract's pricing is confidential.
CEA's board agenda report described the terms as providing energy settlement, resource adequacy and compliance value at a competitive price over the 25-year term.
On-site construction at Willow Rock began in July 2026 after the California Energy Commission granted a permit in December 2025. It is Hydrostor's first utility-scale project in the United States.
The guaranteed commercial operation date is June 2031. CEA ratepayers will not be charged until construction is complete. The agency's long-term goal is 100% clean energy by 2035.
