Construction of the 293MWh BH-ESS is anticipated to commence in the fourth quarter of 2023, with commercial operation expected by the end of the second quarter of 2024, and is expected to supply carbon-free energy to Northern California


PG&E, Energy Vault team up for 293MWh BH-ESS in US. (Credit: American Public Power Association on Unsplash)

Switzerland-based Energy Vault and Pacific Gas and Electric Company (PG&E) have partnered for a utility-scale battery plus green hydrogen energy storage system (BH-ESS) in California, US.

The Swiss energy storage solutions provider will own, operate, and maintain the 293MWh BH-ESS and provide dispatchable power to PG&E, under a long-term tolling agreement.

Construction on the project is anticipated to commence in the fourth quarter of 2023, with commercial operation expected by the end of the second quarter of 2024.

Upon completion, the project is expected to be the first-of-its-kind and the largest utility-scale green hydrogen project in the US.

It will supply carbon-free energy for the Calistoga community in Northern California for 48 hours during planned outages and potential Public Safety Power Shutoffs (PSPS).

In addition, the system’s capacity can be expanded to 700MWh in the future, allowing it to operate for longer without refuelling.

PG&E North Bay and North Coast regional vice president Ron Richardson said: “PG&E selected Energy Vault’s innovative hybrid architecture and design to create a cost-effective, community-scale, fully carbon-free microgrid that can store and dispatch on-demand renewable energy.

“This breakthrough collaboration between PG&E and Energy Vault provides a template for future, renewable community-scale microgrids that successfully integrate third-party distributed energy resources, which is expected to cost customers less than the benchmark set by state regulators based on the alternative use of mobile diesel generators.”

Last month, PG&E submitted the project contract to the California Public Utilities Commission (CPUC), seeking final approval for the project by 15 May 2023.

The new BH-ESS will replace the mobile diesel generators used to energise PG&E’s Calistoga microgrid during broader grid outages.

Also, the system will be designed such that it occupies less than one acre of land, and serve as a model for its utility-scale hybrid storage system deployments in the future.

Energy Vault chairman and chief executive officer Robert Piconi said: “We are setting a new benchmark for what can be achieved with an innovative design that integrates the most advanced energy storage mediums in order to deliver a fully renewable green hydrogen battery energy storage system.

“Our engineers designed this innovative hybrid energy storage system leveraging Energy Vault’s technology-neutral integration platform and energy management software.

“This project represents another key customer validation of our strategy and our unmatched, industry-leading ability to bring the most innovative short, long and ultra-long duration energy storage technologies to our customers with proprietary gravity, green hydrogen and hybrid battery solutions as we deliver on our mission of enabling a renewable world.”