Long Duration Energy Storage Program

Background The Long Duration Energy Storage (LDES) program has been allocated over $247 million to invest in the demonstration and deployment of non-lithium-ion long duration energy storage technologies across California, paving the way for opportunities to foster a diverse portfolio of energy storage technologies that will contribute to a safe and reliable future grid. The LDES program, in part, leverages funding made available through the California Climate Investments initiative, and is aligned with its goals of prioritizing disadvantaged communities and providing energy savings, direct economic benefits, emission reductions, and supporting grid resiliency. LDES technologies play an important role in achieving California's zero carbon goals. As the deployment of intermittent renewable energy sources accelerates and the frequency of extreme weather events increases due to climate change, there is a growing need for storage technologies with extended energy-duration capabilities to maintain grid reliability. The LDES program prioritizes projects that will benefit Justice Communities and maintains a strong focus on projects that benefit Native American tribes in California. LDES Program Projects Expand All Collapse All Hoopa Valley Public Utilities District In 2026, the CEC awarded the Schatz Energy Research Center, part of Cal Poly Humboldt Sponsored Programs Foundation, a $15.7 million grant to install a front-of-the-meter vanadium flow battery system, co-located with solar photovoltaic generation and lithium-ion batteries to support the Hoopa Valley Public Utilities District. The LDES system will participate in energy markets during normal grid operations and provide backup power to the distribution-level circuit during outages, demonstrating LDES technology’s ability to deliver wholesale market revenue while providing reliability and resiliency. The system is expected to be operational in 2029. Valley Children’s Hospital In 2025, the CEC awarded Charge Bliss, Inc. a $28 million grant award to deploy an LDES system to support a microgrid serving the Valley Children’s Hospital in Madera, CA. The project will provide energy resiliency in a region that is increasingly at-risk for significant and prolonged power outages. Additionally, it will provide a roadmap for deploying clean backup power systems at acute care facilities, and demonstrate the reliability of LDES as a viable alternative to fossil fuel-based resources. The system is expected to be commissioned in 2029. Pacific Steel Group In 2025, the CEC awarded Pacific Steel Group a $14 million grant to deploy a 4 MW/32 MWh vanadium flow battery LDES system to support the Mojave Micro Mill project in Mojave, California. The first-of-a-kind Mojave Micro Mill innovative clean energy project will support a $630 million zero carbon emission electrified rebar steel mill plant. The LDES system will be integrated with the plant’s on-site microgrid and solar PV system to provide clean electricity, reliable backup power, optimize renewable energy use, and support the energy-intensive, rapidly fluctuating demands typical of steel mill operations. The system is expected to be commissioned in 2027. Naval Base San Diego In 2024, the CEC awarded Eos Energy Storage, LLC. an $8 million grant to deploy a 1 MW/8 MWh zinc hybrid cathode battery LDES system at Naval Base San Diego as part of a microgrid project. The Navy has committed $3.9 million in funding toward constructing the microgrid with 300 kW of solar PV to support its critical facilities. The LDES system will help meet the Base’s 14-day backup power requirement for critical operations while enhancing the reliability and resilience of its energy infrastructure. The system is expected to be commissioned in 2027. Marine Corps Base Camp Pendleton, San Diego County