Nation’s Largest Urban Battery To Take Center Stage Near San Francisco

Tucked in Southern California’s Menifee, about 50 miles southeast of Los Angeles, one of the nation’s largest battery storage facilities is taking shape. The Nova Power Bank sits on 43 acres where a former natural gas power plant once operated. It’s home to roughly thousands of modular battery units and represents a major step in California’s push for clean energy.

The facility can store up to 2,000 megawatts of electricity. That’s enough power to run about 680,000 homes for four hours at full discharge.

The batteries store electricity during off-peak hours, when renewable energy sources like wind and solar produce more power than the grid needs. That stored energy then gets released during peak demand periods, helping keep the lights on across Southern California. In grid emergencies, battery storage systems can respond in as little as 10 milliseconds, making them a critical tool for stabilizing the grid.

Construction reportedly began in August 2024, with phased completion targeted for 2025 onward. The project uses a multi-phase approach, meaning parts of the facility can become operational before the whole thing is finished.

Construction on Nova Power Bank kicked off in August 2024, with sections coming online in phases before full completion.

The batteries use lithium-ion technology and are built in a modular design, making them easier to maintain and expand.

Several major utilities are reportedly partnered with the project, involving major utilities like Southern California Edison as the primary power buyer. Peninsula Clean Energy and San Diego Gas & Electric are also involved.

Together, they help distribute the stored electricity across multiple service areas throughout the region.

California’s already a national leader in battery storage. The state runs over 200 utility-scale battery systems and is making strong progress toward 100% clean electricity goals. The Darden Clean Energy Project, owned by IP Darden I, LLC, a subsidiary of Intersect Power, is expected to become the largest battery energy storage system in the world.

Nova Power Bank joins other large facilities, including the Edwards & Sanborn project at 3,287 megawatt-hours and the Darden Clean Energy Project at 4,600 megawatt-hours. The Edwards & Sanborn project, located in Kern County, used 1.9 million PV modules supplied by First Solar as part of its solar-plus-storage design.

Beyond powering homes, the project also brings jobs during construction and ongoing operations. It’s also part of California’s broader goal of running entirely on clean electricity by 2045.

Converting a former fossil fuel site into a battery storage hub reflects that shift in direction. For hundreds of thousands of Southern California households, it’s a sign that the state’s energy future is being built right now.

✅ Claims in this article were verified using AI-assisted fact-checking.