Over the past several years, the deployment of battery storage systems has grown significantly throughout California, growing from 500 megawatts (MW) in 2019 to over 13,300 MW statewide in 2024.

Likewise, battery storage system technologies and standards have also matured over time.

Battery storage systems are one of the key technologies California relies on to enhance reliability and reduce dependency on polluting fossil fuel plants. Battery storage systems soak up clean energy in the daytime when the sun is shining, store that electricity, and then export it to the grid in the evening hours when the sun is down.

In 2024, California made historic progress in clean energy deployment. The state brought more than 7,000 MW online – the largest amount in a single year in California’s history. This includes over 4,000 MW of new battery storage.

California’s current installed battery storage capacity is over 20 percent of California’s peak demand. The state’s projected need for battery storage capacity is estimated at 52,000 MW by 2045.

On March 13, 2025, the California Public Utilities Commission (CPUC) enhanced the safety of battery energy storage facilities by establishing new standards for the maintenance and operation of such facilities, and increased oversight over the emergency response action plans for the facilities, which play a crucial role in California’s transition away from fossil fuels.

The CPUC modified General Order 167, which currently provides a method to implement and enforce maintenance and operation standards for electric generating facilities, in order to add new safety standards for the maintenance and operation of battery energy storage systems, as required by Senate Bill (SB) 1383, which relates to electric storage facilities’ standards and records.

SB 1383 law vests the CPUC with regulatory authority over public utilities, including electrical corporations. Existing law establishes an Independent System Operator (ISO) as a nonprofit public benefit corporation and, among other things, requires the ISO to ensure efficient use and reliable operation of the electrical transmission grid, as specified.

The Public Utilities Act requires the commission to implement and enforce standards for the maintenance and operation of facilities for the generation of electricity owned by an electrical corporation or located in the state to ensure their reliable operation. Existing law requires the ISO to maintain records of generation facility outages and to provide those records to the Electricity Oversight Board and the commission on a daily basis.

SB 1383 also requires the CPUC to implement and enforce standards for the maintenance and operation of facilities for the storage of electricity owned by an electrical corporation or located in the state. The bill also requires the ISO to maintain records of storage facility outages and to provide those records to the CPUC on a daily basis.

On February 13, the CPUC also made explicit that battery storage facility owners must develop emergency response and emergency action plans, as required by California Senate Bill 38 (SB 38), signed into law in October 2023, which mandates that battery energy storage facilities in California establish emergency response and action plans, coordinate with local agencies, and submit plans to the relevant county and city.

In addition, the CPUC made other technical updates to the standards to improve safety, reliability, and effectiveness of operation and maintenance activities, such as establishing technical logbook standards for battery storage systems and expanding requirements for emergency plans that relate to all electric generating facilities.