As a major fire abated near San Jose, Calif., that ravaged one of the world’s largest battery energy storage facilities, investigators have begun an onsite probe of the cause. The blaze that began Jan. 16 destroyed most of a 300-MW lithium-ion battery array at Vistra Energy’s 750-MW Moss Landing storage facility at a decommissioned gas power plant site. 

“There are still no active flames, while a limited amount of smoldering is continuing to abate,” Vistra had said in a statement posted to an incident website. Separately, the U.S. Environmental Protection Agency said the air around the plant is safe. No damage cost estimate was provided. 

Vistra said surface sampling continues to be conducted and analyzed by CTEH, a unit of consultant Montrose Environmental Group, working with EPA and Monterey County Health Dept. LG Chem, the battery manufacturer, is on-site, and information is being shared.

In a proposed change days later, the California Public Utilities Commission said it would tighten operating, maintenance and emergency response rules for battery sites. If approved at its March 13 meeting, the agency would grant regulators authority to set legal requirements for energy storage safety. 

California is making a major investment in battery storage, with the state projecting need for 52 GW of storage capacity by 2045, up from the current 13.3 GW. although market impacts in the U.S. from tariffs and other Trump administration rumored trade measures remain unclear.

At a Jan. 21 meeting, the Monterey County Board of Supervisors unanimously voted to approve an emergency declaration and to urge that Moss Landing remain offline while the fire is investigated. “We are calling for nothing less than a full commitment ... until the situation is fully safe,” County Supervisor Glenn Church said prior to the meeting. ”We’ve committed to work closely with our community partners and local officials to determine how best we can help, and we’ll have more information to share on this in the coming days,” a Vistra spokesperson told the board.


'Preparedness'

County emergency response officials declared the fire a major operations incident and a local disaster that required closing nearby Highway 1 and one-day evacuation of an estimated 1,500 people.

A county fire chief, Joel Mendoza, said on Jan. 17 that a fire suppression system housed in one of the facility’s battery racks had failed, allowing the fire to spread. 

The commission response was “an important next step for assuring communities that accidents like this won't happen again,” says Dustin Mulvaney, a San Jose State University environmental studies professor and expert on lithium-ion batteries who monitors California’s fast-growing energy storage sector. 

“This fire event may cause some proposed projects to redesign batteries housed in buildings,” as some are at Moss Landing, Mulvaney says, “but it will not slow the deployment trajectory.”

Operated by Iriving, Texas-based Vistra Energy, the facility stores surplus energy generated from renewable sources and releases it during periods of high demand. 


Expansions

Moss Landing has undergone two expansions since its original 300-MW development was completed in 2020, the area where the fire occurred and was confined to. Past safety incidents include several battery melting events in 2022, with suppression preventing a fire.

In a 2024 report, ENR noted completion of the battery site's third expansion that added 350 MW of capacity. Everyone on the site was given stop-work authority, it notes, and design-builder Burns & McDonnell said it worked closely with local fire officials and employees on thermal runaway risks and fire prevention responses.

It could not be determined at ENR posting time if the firm is assisting with the fire investigation.

The American Clean Power Association last year released a model ordinance for states and municipalities in regulating energy storage system safety, permitting, siting, environmental compliance and decommissioning.