CPUC Adopts New Rules Governing Safety of Battery Energy Storage Systems
On March 13, 2025, the California Public Utilities Commission (CPUC) modified General Order (GO) 167 to establish new standards for the maintenance and operation of battery energy storage systems (BESS) and increase oversight of the emergency response action plans for the facilities. Unlike most GOs, which apply only to investor-owned regulated utilities, modified GO 167 applies to all battery energy storage systems located in California.[1]
Replacing fossil fuel-based power generation with power generation from wind and solar resources is a key strategy for decarbonizing California’s electrical grid. Energy storage allows electricity systems to remain in balance despite variations in wind and solar availability by storing energy in the middle of the day when solar and wind energy supplies are abundant, and often in surplus, and discharging it in the evenings when demand for energy spikes. Battery energy storage projects are essential for California to provide reliable energy supplies and meet its goal of a zero-carbon future by 2045.
The state’s projected need for battery storage capacity is estimated at 52,000 MW by 2045. In 2024, 7,000 MW of new storage were added, and the development of these facilities is accelerating throughout the state.
However, safety concerns have also grown with the proliferation of new systems. Batteries have caught on fire at several facilities, including fires at BESS facilities in Moss Landing (2025), Otay Mesa (2024), Escondido (2024) and others. The California Legislature has responded with several statutes including Senate Bill (SB) 1383, which requires the CPUC to implement and enforce standards for the maintenance and operation of facilities for the storage of electricity, and SB 38, which requires each BESS in California to have an emergency response and emergency action plan that covers the premises of the BESS.
The modification of GO 167 further implements SB 1383 and SB 38. It clarifies that the compliance requirements of GO 167 apply to all BESS in the state, with exemptions only determined by the size of the facility. For example, BESS that are 50 MWs and greater in size are subject to all requirements of GO 167, while smaller BESS are exempt from certain standards. GO 167’s requirements are broad and include requirements to maintain accurate logbooks, comply with safety-related reporting requirements and outage reports, and cooperate with any audits or inspections conducted by the CPUC. Failure to meet these standards or comply with reporting requirements authorizes the CPUC to issue violations and impose sanctions.
GO 167 further requires that BESS facilities comply with GO 167’s “Maintenance Standards” and “Operation Standards.” These “standards” are high-level guiding principles that must be incorporated into a Maintenance Plan and an Operation Plan, both of which must be submitted to the CPUC to demonstrate the facility has a comprehensive safety program in place; clear organizational structure and reporting responsibilities; ongoing training to ensure safe and reliable facility operation; and clear procedures for addressing startup, shutdown, charging, discharging, failure detection, alarm response, and reasonably anticipated abnormal and emergency conditions, among other requirements. The Operation Standards also directly implement SB 38, mandating that BESS facilities plan and prepare for and respond to reasonably anticipated emergencies on and off the site, by training personnel in the emergency plan periodically; developing emergency plans and coordinating with local emergency management agencies; and submitting the emergency response and emergency action plan to the county, local emergency management agencies, local first response agencies, and if applicable, the Authority Holding Jurisdiction (AHJ) and the city where the facility is located.
If you have questions regarding how GO 167 will affect your operations, do not hesitate to reach out to the authors or any of Cox Castle’s renewable energy experts.
[1] The CPUC’s summary report on the modification noted that “[t]he breadth of the legislation extends our authority to many electric generators who have consistently maintained that they are not otherwise subject to our regulation.”
See page 6 at https://docs.cpuc.ca.gov/PublishedDocs/Published/G000/M558/K715/558715484.pdf
