Hydrostor Files Second Application for Certification for 500 MW x 8 Hour (4,000 MWh) Gem Energy Storage Center

Hydrostor is advancing two of the largest long-duration energy storage facilities in California, totaling 900 MW and 7,200 MWh, enhancing regional reliability and supporting the State’s transition to a carbon-free renewable future

San Francisco, Dec. 01, 2021 (GLOBE NEWSWIRE) — Gem A-CAES LLC, a subsidiary of Hydrostor, today filed its Application for Certification (“AFC”) with the California Energy Commission (“CEC”) for development of a 500 MW, 4,000 MW-hour (“MWh”) energy storage facility located outside of the City of Rosamond, Kern County, California. The Gem AFC filing follows Hydrostor’s recent announcement and AFC filing of the Pecho Energy Storage Center, a 400 MW x 8-hour A-CAES project located in San Luis Obispo County.

The Gem Energy Storage Center (“Gem” or the “Project”) will deploy Hydrostor’s proprietary Advanced Compressed Air Energy Storage (“A-CAES”) solution. The state-of-the-art project will provide large-scale, long-duration energy storage for the region with no fossil fuel consumption and no greenhouse gas emissions. With a commercial operation date (“COD”) as early as 2026, Gem will play a vital role in helping meet the region’s future energy supply and reliability needs, allowing California’s growing solar and wind resources to be directly converted into reliable, on-demand peak capacity for the High Desert, the greater Los Angeles region and the broader California grid.

Gem’s ability to flexibly deliver 500 MW of stored energy for eight hours without relying on fossil fuels or other polluting resources would make it one of California’s largest single new energy storage facilities. Gem would surpass all existing battery energy storage projects in California in terms of both megawatts delivered and duration of generation, with an expected capital investment of $975 million.

Long-duration energy storage is one of the cornerstone solutions to a carbon-free renewable energy future. Gem’s ability to deliver 500 megawatts of carbon-free electricity for 8 hours will be comparable in size and resiliency to some of California’s largest fossil-fueled powerplants. Gem’s quick-starting, flexible, and dispatchable long-duration energy supply will have the ability to ramp-up and down through a wide range of electrical output. This flexibility over long durations is vital in facilitating the integration of onshore and offshore renewable energy and will play a critical role in helping achieve California’s climate change objectives.

State law designates the CEC to serve as the Lead Agency for the California Environmental Quality Act (“CEQA”) review and permitting of the facility. Gem’s filing of its AFC with the CEC will initiate the very thorough and comprehensive public review process. Kern County and numerous other local, state, and federal agencies, as well as interested community stakeholders, will be closely involved in the CEC-led review. 

The development of the Project will provide a pathway for local skilled labor to shift to the green economy as the community continues to expand and build out new renewable energy facilities.   The Project is expected to provide an estimated peak workforce of 700 jobs during its 4 years of construction. Once operational, Gem will create 30 to 40 full-time equivalent, good paying jobs. The Project will also generate significant new property tax revenues for Kern County and is expected to generate over $500 million in direct and indirect regional economic benefits during its commercial lifespan.  

Gem will interconnect at the existing Whirlwind Substation (CAISO delivery) or the planned Rosamond Switching Station (LADWP delivery). The Project is strategically located to provide enhanced utilization of both existing and future renewable energy resources serving California and the High Desert. Gem’s emissions-free operations will play a vital role in helping meet California’s future power supply needs, significantly reducing the frequency of large-scale blackouts.  

The California Public Utilities Commission (“CPUC”) adopted a decision in June 2021 directing the procurement of 1,000 MW of long-duration – energy for eight hours or longer – energy storage to be online between 2026-2028. This decision follows years of studies and stakeholder input that culminated in this first-of-its-kind mandate to maintain the reliability, flexibility, and resilience of the electrical grid as it transitions to achieve legislated greenhouse gas reductions. Hydrostor applauds the leadership of the CPUC and is confident that Gem will be a key element in California’s clean energy transition.

Curtis VanWalleghem, CEO, Hydrostor, said, “Today’s filing marks the second of many important milestones in the implementation of Hydrostor’s commitment to helping California meet its recognized long-duration energy storage needs. Deployment of Hydrostor’s unique combination of being a proven, cost effective and carbon-free long duration storage solution will greatly enhance California’s program to fully transition to a reliable and carbon-free energy future. Our A-CAES facilities are designed to operate safely and efficiently for over 50 years with zero degradation.  We look forward to working closely with the citizens of Kern County to earn their trust and support on our way to becoming a valued member of the community. Gem complements our previously announced 400 MW, 3,200 MW-hour Pecho Energy Storage Center located in San Luis Obispo County.”


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About Hydrostor

Hydrostor is a long-duration energy storage solutions provider that provides reliable and affordable utility integration of long-duration energy storage, enabling grid operators to scale renewable energy and secure grid capacity. Hydrostor supports the green economic transition, employing the people, suppliers, and technologies from the traditional energy sector to design, build, and operate emissions-free energy storage facilities. Hydrostor has developed, deployed, tested, and demonstrated that its patented Advanced Compressed Air Energy Storage (“A-CAES”) technology can provide long-duration energy storage and enable the renewable energy transition. A-CAES uses proven components from mining and gas operations to create a scalable energy storage system that is low-impact, cost-effective, and can store energy from 5 hours up to multi-day storage where it is needed. Hydrostor has projects worldwide in various development stages for providing capacity of over 200 MW each.

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