Dive Brief:

• California would establish new maintenance and operation standards and increase emergency response plan oversight for battery energy storage facilities under a California Public Utilities Commission proposal published Monday. 
• The proposal comes less than two weeks after fire destroyed most of a 300-MW battery array at Vistra Corp.’s Moss Landing Energy Storage Facility near Santa Cruz, sparking calls for stricter oversight from local elected officials. Both Vistra and CPUC’s Safety and Enforcement Division are investigating the incident, they said.
• The CPUC plans to vote on the proposal, which it expects to have “no significant cost,” at its March 13 voting meeting.

Dive Insight:

The Jan. 16 fire was the most destructive of three safety incidents to occur at the Moss Landing Energy Storage Facility since 2020. A fourth incident occurred in September 2022 at an adjacent 182.5-MW battery installation owned and operated by Pacific Gas & Electric.

No injuries or deaths were reported in the Jan. 16 incident. Federal air quality monitoring concluded Jan. 20 after finding no risk to public health, the U.S. Environmental Protection Agency said. 

But local elected officials nonetheless raised alarms about the facility and the broader safety profile of battery energy storage facilities, with Monterey County Supervisor Glenn Church calling the fire a “worst-case scenario” and California Assemblymember Dawn Addis, D, vowing to “[explore] all options for preventing future battery energy storage fires from ever occurring again on the Central Coast.”

The CPUC’s proposal implements a 2022 state law requiring the regulator 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 proposal modifies a 2004 order enabling maintenance and operation standards at electric generating facilities to add new safety standards specifically for battery energy storage systems, the CPUC said.

That order, known as GO 167, was developed at a time when electrochemical energy storage facilities were not widely deployed and thus did not consider safety issues related to them specifically, the CPUC said.

Energy storage capacity in California has grown from about 500 MW in 2019 to about 13,300 MW last year, including nearly 11,500 MW of utility-scale storage, according to the CPUC.

California has experienced at least 10 notable energy storage safety incidents in the past five years, including two incidents at Terra-Gen’s 139-MW Valley Center Energy Storage Facility in April 2022 and September 2023, one at San Diego Gas & Electric’s 20-MW Kearny South Energy Storage Facility in April 2024, and one at REV Renewables’ 250-MW Gateway Energy Storage Facility in May 2024, the CPUC said.

The modified GO 167 includes 18 storage-specific maintenance standards covering maintenance procedures and documentation, storage and condition of spare parts, equipment performance and condition, chemistry control and regulatory compliance, among other items. Twenty-eight storage-specific operating standards cover operation procedures and documentation, engineering and technical support, routine inspections, preparation for on- and off-site emergencies, emergency grid operations and more.

The CPUC’s proposal also requires battery energy storage facility owners to develop emergency response and emergency action plans as required by a separate state law passed in 2023.