How Could a Hydrogen Storage System Power 2,000 Electric Customers?
Energy Vault Holdings and Pacific Gas and Electric Company (PG&E) have collaborated to deploy and operate a utility-scale battery plus green hydrogen storage system (BH-ESS). Hydrogen Industry Leaders explores how this could power around 2,000 electric customers for 48 hours.

The 293 MWh BH-ESS system is designed to power downtown Calistoga, California, US, and its surrounding area. It will integrate a short-duration battery system for grid forming and black start capabilities, with long-duration fuel cells and a liquid green hydrogen system, to place existing mobile diesel generators.

In accordance with a long-term tolling agreement with PG&E, Energy Vault will own, operate, and maintain the energy storage system while it provides dispatchable electricity. The system’s capacity might be increased to 700 MWh, allowing it to run without refuelling for longer and giving PG&E and the City of Calistoga more flexibility.

Beginning in the fourth quarter of 2025, the project is a key step in achieving the CPUC’s goal of greener types of microgrid production and a significant advancement in the construction of community-scale microgrids.