Until last month, Heather Griffin was only vaguely aware that the massive retired power plant five miles down the road from her community of Prunedale now housed the nation’s largest array of batteries for energy storage.
Then, the California facility caught fire, and it became impossible to ignore.
Prunedale was put under a shelter in place order for days when the fire broke out on Jan. 16, with residents too scared to open windows or turn on their heaters over fears of toxic smoke emitting from the flaming batteries. About 1,200 residents were evacuated from areas closer to the Moss Landing storage facility. Griffin, 55, quickly set up a Facebook group to organize Prunedale residents who had questions for their local officials and Vistra, the Texas-based power provider that operates the plant.
“We want to empower our local residents to get answers on why it was allowed by our local government to be here in the first place,” she said in an interview. “But it’s also ultimately to make sure that this never happens here again. How we get from here to there, that’s all up in the air right now.”
The fire — which grew into the largest battery accident on record — was out a few days later, having destroyed most of a large array of batteries at the facility. But days later, Monterey County supervisors voted to declare a state of emergency, warning Vistra not to restart it. Supervisor Glenn Church said at the meeting that the battery technology “is ahead of the government’s ability to regulate it.”
It was a stark reminder of a key tension as California and other states transition to a zero-carbon electric grid. Sites like Moss Landing are essential for storing up wind and solar power and discharging it when power is needed most. But lawmakers and regulators are increasingly worried about whether those sites should be near people’s homes, schools and businesses.
The industry also faces potential headwinds as the Trump administration pulls back on federal support for clean energy development, including the potential reversal of tax credits that have helped lower the cost of new batteries.
State Assemblymember Dawn Addis, a Democrat who represents the district that houses Moss Landing, introduced a bill in late January that would impose a 3,200-foot setback for battery storage facilities from homes and schools, bar them from environmentally sensitive areas and rescind an expedited state permitting process for the sites. The California chapter of the American Clean Power Association was quick to criticize the bill as “overbroad” and a barrier to the state’s energy goals.
Last week, the Orange County Board of Supervisors also approved a 45-day moratorium on battery storage while the county reviews its regulations.
The state Public Utility Commission last week also proposed new maintenance and operations standards for battery systems, including more intense emergency plan requirements. Those standards — which had been in the works for more than a year — are set for a vote in March.
Industry groups and outside experts say that battery systems are safe. They contrast Moss Landing’s relatively outdated design in a retired power plant with newer systems that are custom-made to house batteries with state-of-the-art fire response. Air quality tests in California have not shown any toxic emissions from the fire, although researchers at San Jose State University last week reported that soil samples had detected “unusually high concentrations” of heavy metals near the site.
Data from the Electric Power Research Institute (EPRI) has shown that, as the number of battery storage installations increases exponentially, the number of accidents has stayed the same, an indication that they are getting safer.
“Facilities that are located within retrofitted buildings that were not specifically engineered to house energy storage systems are an anomaly, representing less than 1% of existing facilities,” Noah Roberts, vice president of energy storage for the American Clean Power Association (ACP), wrote in an email. “After the incident is resolved and there is a thorough investigation, the industry will ensure the lessons learned are applied to prevent future incidents and inform safety standards and best practices.”
Still, the fire comes as lawmakers and regulators are looking more skeptically at battery sites, threatening to impose new permitting or safety requirements that could make them harder to build — even as the grid needs them more.
A handful of communities and counties in California are considering permitting rules for batteries, even as the state works on its own fire code for the sites. A bill in Texas would require battery developers to get a permit from the state, with requirements including setbacks from buildings and emergency response plans.
“Battery storage facilities being located in tiny towns with Volunteer Fire Departments on dead end streets puts local residents in danger,” wrote Texas state Rep. Ellen Troxclair, a Republican, that bill’s sponsor, on Facebook.
While battery systems can go anywhere, they need to be connected to the grid and developers favor sites that have existing ties. Those could be substations or retired power plants that may already be close to developments, and advocates warn that zoning limits could make it difficult to bring batteries online quickly.
‘De facto moratorium’
The concern came to a head late last year in San Diego County, where lawmakers weighed a potential moratorium on new battery projects until the county could write new rules that included requirements that batteries be placed far away from homes and buildings. The measure, introduced by supervisor Jim Desmond, came in response to three battery fires in the county.
Desmond’s proposal met with fierce backlash from clean energy developers, who contrasted the measure with California’s own data saying that it will need some 52,000 MW of energy storage capacity by 2045 to meet demand with a decarbonized grid. Speaking at a public meeting in December, Josh Adams, a fire expert affiliated with clean energy developer NextEra Energy, called the rules a “de facto moratorium” that was overly broad.
The moratorium and the rules ended up not passing; instead, the county directed staff to draft new safety rules while the state worked on a separate fire code. Hunter McDonald, a policy adviser for land use in Desmond’s office, said the effort was designed to “pump the brakes a bit” after supervisors discovered that the county did not have any specific zoning rules for battery storage systems.
“Yes, we might be gumming up the works in the short term, but once the rules are in place, then everybody will know what they need to do to maintain safety,” McDonald said in an interview. “We don’t want to look back 10 or 15 years from now and say ‘if only we had drafted more specific rules.’”
There’s not much precedent for San Diego’s effort. According to a2023 report by the Pacific Northwest National Laboratory, only a handful of counties, states or cities have specific regulations about battery storage. Instead, the systems may be lumped in with power plants or electrical infrastructure such as substations.
“It’s important that the unique nature of energy storage is recognized when there are regulations being developed,” said ACP’s Roberts. “The best practices we recommend ensure that safety is maximized without reducing artificially the benefits that can be provided to communities in reliability and cost.”
ACP offers its own model ordinance for governments to adopt. That ordinance, in turn, relies on a standard published by the National Fire Protection Association, a nonprofit group that develops codes and standards to reduce fire risk. The organization’s battery storage system standard, NFPA 855, lays out safety recommendations for design, installation and operation of energy storage systems, based on years of work by a technical body.
ACP has also worked with regulators to explain the unique nature of battery fires and what type of suppression methods might be most useful. For example, ACP persuaded Maryland’s Public Service Commission to adopt a safety standard for battery facilities after lawmakers there proposed legislation that would require a self-contained fire suppression systems — something ACP says is not necessary and would only add cost.
The data on battery fires
The question, then, is what risk battery systems pose as they proliferate.
A 2024 study from advisory firm Clean Energy Associates that studied 30 GWh worth of battery systems found that 26 percent of them had quality issues related to fire detection and suppression, with a further 18 percent having issues related to thermal management. Most of those, the report found, were at the system level rather than with the battery technology. The issues ranged from improper wiring to disconnected pipes that could lead to short-circuiting events.
On the other hand, the database of storage accidents collected by EPRI shows that the incidents are rare — and getting rarer. There were 11 failures in 2021 when the world had roughly 12 GW of batteries installed; in 2023, with more than four times that installation, there were just 15 incidents.
What’s more, the data echoes CEA’s finding that battery cells are typically not at fault.
“This really points to the fact that these are problems we know how to solve,” said Lakshmi Srinivasan, team lead for energy storage and distributed generation at EPRI.
Scott Murtishaw, executive director of the California Energy Storage Alliance, said that in the aftermath of the San Diego vote, he is making sure that local officials and fire departments understand the track record of storage and what experts recommend. For example, he said, a proposal in San Diego that would have required 10 feet of separation between battery racks, as opposed to the 3 feet recommended by NFPA, would have raised costs significantly for new battery projects.
“We want to avoid more bespoke restrictions that wouldn’t be found in NFPA 855,” said Murtishaw. “We want standards based on those developed by experts, not based on misinformation.”
Still, the Moss Landing fire serves as a reminder of the education and community outreach that developers need to do to get community buy-in, especially for a technology that most residents and regulators still aren’t familiar with. A previous fire at the site spurred California lawmakers to pass a bill requiring emergency response plans at battery packs; it remains to be seen what the fallout of the latest fire will be.
Vistra has not announced plans to restart the site, but California is poised to install new batteries at a rapid clip. That, said San Jose State University environmental studies professor Dustin Mulvaney, means that community buy-in will be increasingly important.
“There are some parallels with the nuclear industry, where there were mistakes, but it took a lot of learning from those mistakes to make sure they didn’t happen again,” said Mulvaney, who studies Moss Landing. “It may be with storage that we’ve already figured it out. But it will be important to make sure the community understands and supports that.”
