Huge 'Micro-Grid Storage Tank' Delivered To Calistoga; Here's Why

CALISTOGA, CA — Parking restrictions and road closures were in place as a new micro-grid storage tank was delivered to Calistoga early this week after making its way Friday through the city of Napa.

The delivery was expected to take place between midnight and 6 a.m. to minimize disruption and ensure secure transportation of the storage tank to the end of Washington Street, city officials said.

Another round of parking restrictions and limited road closures that were initially scheduled for Tuesday morning from midnight until 8 a.m. on Lincoln Avenue and Washington Street were rescheduled to Wednesday morning from midnight until 8 a.m.

The restrictions were necessary to accommodate the tank trailer as it left the city, to ensure there was enough space to maneuver the trailer without obstructions.

The Calistoga Police Department was expected to keep the public updated about any further changes to the schedule.

Calistoga Resiliency Center

The storage tank is for the Calistoga Resiliency Center — BH-ESS — constructed by Energy Vault Holdings, Inc. for Pacific Gas and Electric Company on less than one acre of land at 204 Washington St. Upon completion, the Calistoga Resiliency Center will be the first of its kind and the largest utility-scale green hydrogen energy storage project in the United States.

The battery portion of the system will be used to support grid forming and black start capabilities. The system will be prepared to power downtown Calistoga and the surrounding area for up to 48 hours during potential Public Safety Power Shutoffs —PSPS — which occur when the powerlines serving the surrounding area must be turned off for safety due to high wildfire risk. PG&E’s proposal for the system was approved by the California Public Utilities Commission —CPUC— in April 2023.

Energy Vault’s BH-ESS will replace the traditional mobile diesel generators currently used to energize PG&E’s Calistoga microgrid during PSPS events in the area. The project represents a major advance in community-scale microgrid development and a significant step toward realizing the CPUC’s vision of cleaner forms of microgrid generation.

"We greatly look forward to not only its delivery but most importantly to the sustainability benefits it will bring to the Calistoga community," said Marco Terruzzin, Chief Commercial and Product Officer, Energy Vault. "Our partnership with California’s largest public utility is yet another example of the growing recognition that optimizing grid resiliency and economics toward achieving decarbonization goals requires innovation that leverages multiple technologies and a ‘fit-for-purpose’ customer-centric approach when designing energy storage solutions. The City of Calistoga and PG&E have been excellent partners for Energy Vault, and we are excited to bring this innovative project online ... "

Under a 10.5-year agreement, Energy Vault will provide "Distributed Generation-Enabled Microgrid Services" — a type of energy service that involves using grid-forming generation and storage resources, to provide energy, fault current contribution and to regulate voltage and frequency within the utility’s established parameters to enable the islanding of the Calistoga microgrid during PSPS outages. The solution is designed to operate during PSPS events, serving all the load within a safe-to-energize area in the city of Calistoga, including critical facilities such as fire and police stations, and shared services in the downtown and surrounding area.

The energy storage system is owned, operated and maintained by Energy Vault while providing dispatchable power under a long-term tolling agreement with PG&E. The Company will leverage its VaultOS™ Energy Management System to control, manage and optimize the BH-ESS operations. The system has been developed under the umbrella of Energy Vault’s H-VAULT™ suite of hybrid configurations leveraging green hydrogen and batteries, to ensure continuity and resilience during PSPS events. By coupling the ultra-long duration capabilities of fuel cells using green hydrogen, and the fast response capabilities of B-VAULT™️ lithium-ion batteries, H-VAULT™ provides the clean, reliable, cost-effective back-up power that is critical to enable islanded microgrids during transmission outages.

"Deploying cost-effective, next-generation energy supply and long-term storage technologies is essential to ensuring grid reliability and to achieving PG&E’s goal of a net zero energy system by 2040," said Mike Delaney, vice president, Utility Partnerships and Innovation. "PG&E is developing a portfolio of promising new forms of electricity generation and storage technologies, and identifying the right applications that will support the further proliferation of these technologies at the lowest capital cost and highest-impact locations."