A Switzerland-based energy storage group with U.S. headquarters in California has joined with Pacific Gas & Electric (PG&E) to deploy a hybrid microgrid energy project in Calistoga, California.
Energy Vault and PG&E on September 25 announced the successful completion and commercial operation of the Calistoga Resiliency Center (CRC), which will serves customers in and around downtown Calistoga, a small town in the northern Napa Valley. The microgrid integrates advanced hydrogen fuel cells with lithium-ion batteries. The companies on Thursday called the facility a “landmark project [that] provides a unique, fully sustainable solution to address power resiliency amidst the growing challenges of wildfire risk in California.”
The CRC will support the need for power in the area, particularly during wildfires and other extreme weather events. The 293-MWh microgrid system is designed to enable Calistoga to maintain power during Public Safety Power Shutoffs (PSPS), a utility protocol deployed to mitigate the risk of wildfires from electrical equipment.
The companies said the microgrid will deliver at least 48 hours of continuous supply with a peak power output of 8.5 MW during PSPS events. “This zero-emission system aligns with California’s Renewable Portfolio Standard (RPS) while meeting PG&E’s multi-day, long-duration energy storage requirements,” according to the companies.
Energy Vault said the system is orchestrated by the company’s technology-agnostic VaultOS Energy Management System, enabling black-start, grid forming and coordinated performance orchestration across all subsystems while communicating with PG&E’s Distribution Control Center.
“This project is a major milestone in our mission to deliver sustainable, resilient energy solutions to communities most vulnerable to climate-driven grid disruptions,” said Craig Horne, senior vice president, Advanced Energy Solutions, at Energy Vault. “The Calistoga Resiliency Center exemplifies the power of innovation and partnership, and it marks a significant step forward in the execution of our ‘Own & Operate’ strategy, which enables us to deliver long-term value through recurring revenue and community impact.”
Hydrogen Fuel Cells
The CRC when operating in island mode utilizes hydrogen fuel cells for electricity generation. It supports black-start and grid-forming requirements of the microgrid, Energy Vault’s B-VAULT DC battery technology works in concert with the fuel cells, ensuring instantaneous response and maintaining grid stability throughout operation.
The use of liquid hydrogen enables extending run time through delivery and transfer into the onsite storage tank without interrupting power supply to the town, and also reduces the cost of resiliency services. The companies said the CRC “serves as a model for Energy Vault’s future utility-scale hybrid microgrid system deployments as the only existing zero-emission solution to address PSPS events that is scalable, bankable, and ready to be deployed across California and other regions prone to wildfires as well as locations where improved grid-resiliency is needed.”
The project was supported by the recent close of $28 million in financing, which includes the completed sale of the investment tax credit associated with the project. It is owned and operated by Energy Vault in collaboration with PG&E as the utility partner and distribution system operator under a long-term energy services agreement.
Energy Vault has said its “Own & Operate” strategy demonstrates the company’s ability to execute its strategic vision while maximizing capital efficiency. The company pointed to its recent completion of the Cross Trails BESS in Texas, the first project to be placed in service under Energy Vault’s growing portfolio of “Owned & Operated” projects.
“PG&E is committed to continually delivering innovations that enhance electric system safety and reliability while driving costs down for our customers,” said Mike Delaney, vice president, Utility Partnerships and Innovation, at PG&E. “The Calistoga Resiliency Center is another step toward fulfilling that commitment. It is the right solution for PG&E, for Calistoga, and for the planet.”
PG&E Microgrids
PG&E has deployed 13 distribution microgrids since 2021 to support communities affected by PSPS incidents. The Calistoga project is the largest, and the first fully renewable system. The microgrids help keep communities and essential services, such as like fire stations, medical facilities, and grocery stores, powered during outages. The microgrids also can power areas where the power lines are underground, or outside of high fire-threat areas or a PSPS weather footprint.
PG&E through its Community Microgrid Enablement Program (CMEP) and Microgrid Incentive Program (MIP) supports the development of community-driven multi-customer microgrids. PG&E in March of this year committed up to $43 million to fund nine new community microgrids in the North Coast region of California.
—Darrell Proctor is a senior editor for POWER.
