Hydrostor has announced that the Willow Rock Energy Storage Center in Kern County, California, has received final permitting approval from the California Energy Commission. The 500 MW / 4,000 MWh advanced compressed air energy storage project is now positioned to be shovel-ready in 2026. Hydrostor claims the facility will provide eight hours of continuous discharge, supporting grid reliability as electricity demand climbs.
The Willow Rock project uses Hydrostor’s advanced compressed air energy storage (A-CAES) technology to store surplus energy and deliver it during peak demand. According to the company, the system can power more than 400,000 homes for over eight hours. The site is expected to bring over $500 million in investment to East Kern County and the greater Antelope Valley, with construction creating thousands of jobs and 40 full-time positions during its anticipated 50-year operational life.
The project has also received a franchise agreement from the Kern County Board of Supervisors and a conditional letter of support as of April 2024, clearing key local government hurdles.
Hydrostor specifically notes the data center sector as a key driver of growing electricity demand. According to Hydrostor Co-Founder and CEO Curtis VanWalleghem, “Our A-CAES technology will be key to reliably meeting expected demand increases driven in part by data centers and AI, while also maintaining affordability for existing customers.”
The Willow Rock Energy Storage Center is Hydrostor’s first planned utility-scale project in the United States. The company is also developing a late-stage project in New South Wales, Australia, and reports a global pipeline totaling seven gigawatts in the United States, Australia, Canada, and the United Kingdom.
Source: Hydrostor







