California requires 55GW of long-duration energy storage by 2045 for grid reliability


A new study released by the California Energy Storage Alliance states that the state needs to deploy up to 45-55GW of long-duration energy storage by 2045 to support critical grid reliability needs and to meet climate targets.

The energy storage capacity required by 2045 for California to meet 100% of its energy demand from renewables is equivalent to over a 150X increase in the amount of energy storage deployed in the state since 2010 and enough energy to power 37 million homes.

By 2030, the state will require 2-11GW of new operational long-duration energy storage.

The study Long-Duration Energy Storage for California’s Clean Reliable Grid has called for an urgent need for the state to begin developing procurement and compensation models for long-duration energy storage now to ensure that these resources can be deployed and online in the next 5-10 years.

Key study findings include:

  • By 2045, long-duration energy storage can provide substantial benefits to California’s grid, relative to a case where California does not have access to long-duration energy storage. These benefits include:  
    • Enabling the retirement of 10GW of fossil-fueled generation.
    • Reducing system capacity costs by $1.5 billion per year from 2031-2045.
    • Increasing renewable energy utilisation by 17%.
    • Reducing in-state use of fossil fuels for electricity generation by 25%.

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Alex Morris, executive director of the California Energy Storage Alliance, said: “Nearly 180GW of the 240GW of incremental capacity installed in California by 2045 will be solar. Long duration energy storage of over four hours duration will be critical to support the solar grid at night, during every evening peak, and then of course on those hours, days, and even weeks when there just isn’t enough sun to meet demand.

“Applying the methodology used in this study can help other solar-dominated Western states to intelligently plan for their future energy storage needs as well- this need for long duration storage is not limited to our state.”

The release of the study follows the California Public Utility Commission calling for the deployment of 1GW of new long-duration energy storage capacity by 2026.

In November 2020, a coalition of eight Community Choice Aggregators in California released the state’s first long-duration energy storage request for offers (RFO) to procure up to 500MW of long-duration storage.

 To access the full report, visit