Energy Vault Achieves Successful Close of $28 Million in Project Financing for the Calistoga Resiliency Center, the World’s First Ultra-Long Duration Hybrid Green Hydrogen Energy Storage Microgrid Serving California’s PG&E

Energy Vault Holdings Inc. (NYSE: NRGV) (“Energy Vault” or the “Company”), a leader in sustainable, grid-scale energy storage solutions, announced the successful close of $28 million in project financing for its Calistoga Resiliency Center (CRC). The financing includes the completed sale of an Investment Tax Credit (ITC) associated with the CRC. This marks a significant milestone in the Company's execution of its growth strategy in owning and operating energy storage assets as first outlined during the May 2024 Investor and Analyst Day.

Currently under site commissioning, the Calistoga Resiliency Center, which Energy Vault developed to serve a tolling contract with Pacific Gas & Electric Company (PG&E), is a state-of-the-art hybrid microgrid energy storage facility that integrates advanced hydrogen fuel cells with lithium-ion batteries, specifically designed to address power resiliency given the growing challenges of wildfire risk in California. As climate change continues to increase the frequency and severity of fire-prone conditions, utilities must occasionally implement Public Safety Power Shutoff (PSPS) events to prevent electrical equipment from potentially sparking fires during extreme weather events.

Energy Vault’s CRC provides a unique fully sustainable solution to this challenge by enabling the isolated Calistoga community microgrid to maintain power during these necessary safety shutoffs. The 293 MWh microgrid system delivers ~48 hours of continuous energy supply with a peak power output of 8.5 MW during PSPS events. When operating in island mode, the CRC utilizes green hydrogen in fuel cells for electricity generation, providing essential power to the community. After supporting 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 CRC achieved mechanical completion, and the system is now under commissioning, with full commercial operation expected in Q2 2025.

This zero-emission system aligns with California's Renewable Portfolio Standard (RPS) while meeting PG&E's multi day long duration energy storage requirements. The entire microgrid is orchestrated by Energy Vault's technology-agnostic VaultOS™ Energy Management System, enabling black-start, grid forming and seamless performance orchestration across all subsystems while communicating with PG&E’s Distribution Control Center.

The CRC serves as a model for Energy Vault’s future utility-scale hybrid microgrid storage system deployments as the only existing zero-emission solution to address PSPS events that is scalable and ready to be deployed across California and other regions prone to wildfires.

"The successful financing of the Calistoga Resiliency Center represents our team’s focus and execution in beginning 2025 by replenishing cash to our balance sheet from the prior year capex spent building the system," said Robert Piconi, Chairman and Chief Executive Officer of Energy Vault. "This is the first of two energy storage assets expected online this quarter as we execute our 'Own & Operate' asset management strategy, and we are looking forward to beginning generating predictable, recurring and high margin tolling revenue streams for the years to come,” Piconi continued. “As California faces increasing wildfire risks, the CRC demonstrates how advanced energy storage technology can help communities maintain critical services and safety during necessary power shutoffs. This facility will play a crucial role in ensuring energy resilience for the Calistoga community during PSPS events while maintaining our focus on innovative and sustainable carbon-free energy solutions."

The project financing success follows through on initiatives first presented during Energy Vault's May 2024 Investor and Analyst Day, demonstrating the Company's ability to execute on its strategic vision while maximizing capital efficiency in its 'Own & Operate' strategy. This milestone reflects significant proactive interest from strategic partners and investors given attractive IRR economics, positioning Energy Vault for continued growth in the rapidly evolving energy storage asset infrastructure market. As previously announced, Energy Vault has executed binding agreements to monetize additional ITC tax credits and secure project financing for its Cross Trails and Customer R&D Center microgrid project, both co-located on adjacent land parcels in Snyder, TX.

Energy Vault | www.energyvault.com