Energy Vault’s mystery partner announced during its Q3 2022 earnings call has been revealed to be PG&E, as the companies plan what it calls a battery-hydrogen energy storage system (BH-ESS) with a minimum of 293MWh of dispatchable carbon-free energy, with the possibility of expanding the system to 700MWh should a use-case present itself. The system is destined for the Northern California city of Calistoga – in California wine country – and will be capable of supplying the downtown and surrounding areas for 48 hours during planned outages and Public Safety Planned Shutoffs (PSPS), which occur most often during wildfire season. The BH-ESS will be owned, operated, and maintained by Energy Vault while providing PGE&E with tolling services under a ten-and-a-half-year…