Largest Green Hydrogen and ESS Hybrid Microgrid in US Goes Online in California

Pacific Gas and Electric Company (PG&E), a California utility, in collaboration with Energy Vault, has launched a long duration energy storage (LDES) hybrid microgrid that combines hydrogen fuel cells and lithium batteries.

Located in Napa County, which has experienced several major wildfires in recent years, the Calistoga Resilience Center (CRC) is designed to maintain the town's power supply during wildfires and serve as a model for net-zero backup systems. The facility integrates hydrogen fuel cells and lithium-ion batteries, capable of supplying electricity to approximately 1,600 users for at least 48 hours if PG&E shuts down the main power grid during emergencies. PG&E stated that the 293 MWh microgrid can continuously provide up to 8.5 MW for at least 48 hours. The lithium battery works in coordination with the fuel cell to handle rapid changes in demand and maintain grid stability. Since the system uses on-site stored liquid hydrogen, additional hydrogen can be delivered and added to the storage tanks without shutting down the system. It is reported that the system operates at a lower cost compared to traditional backup options.

PG&E indicated that the project cost $28 million and serves as "a model for Energy Vault's future utility-scale hybrid microgrid system deployments." Since 2021, PG&E has deployed 13 microgrids, but this California system is the largest of its kind and the first to be fully renewable. It aligns with California's Renewable Portfolio Standard and broader net-zero goals.