By Jondi Gumz
A fire broke out Jan. 16 and burned for four days at Vistra Energy’s flagship lithium battery energy storage plant in Moss Landing, 10 miles from Aptos as the crow flies, closing Highway 1 (a major route to Big Sur) and schools, evacuating
1,200 people, sending out black toxic smoke over agricultural fields known as the world’s salad bowl, and raising safety questions for a proposed $200 million lithium battery storage system on Minto Road outside Watsonville.
Rows of lithium battery racks at the Moss Landing facilities. • Image Courtesy of Vistra
The cause of the fire at the battery storage plant, billed as the world’s largest at tiny Moss Landing, population 239, a fishing harbor next to the Monterey Bay National Marine Sanctuary, is not known.
On Jan. 28, Vistra’s director of community affairs, Brad Watson, told Santa Cruz County supervisors that Vistra wants to find out why the water-based suppression system didn’t work as designed and apply lessons learned to future projects.
U.S. EPA monitoring for hydrogen fluoride put out a statement saying no risk to the public but scientists affiliated with San Jose State University reported toxic metals — microscopic particles of nickel, cobalt and manganese — in soils at the protected Elkhorn Slough a mile away at levels roughly 100 to 1,000 times higher than normal.
Monterey County emergency management director Kelsey Scanlon shared a report but didn’t have the Elkhorn Slough toxic metals data.
Santa Cruz County supervisors voted to have board chair Felipe Hernandez write to the California Public Utilities Commission and California Energy Commission supporting an independent investigation.
Supervisor Manu Koenig wanted the county ag commissioner to do soil testing but Supervisor Justin Cummings felt Vistra should pay.
Vistra has hired CTEH, the company Norfolk Southern hired after a train carrying toxic chemicals derailed in East Palestine, Ohio, catching fire and releasing toxic black smoke.
On Oct. 29, supervisors discussed zoning three sites for battery energy storage near existing PG&E transmission substations to meet the county’s electrical needs.
The sites: Paul Sweet Road and Soquel Drive near Dominican Hospital, Freedom Boulevard near Aptos High School and off Green Valley Road.
Only one has an active application for a permit: Minto Road near Green Valley.
This zoning is to return in April and Koenig asked for permitting stricter than the state.
Experts say battery storage helps solar contribute to the electricity supply when the sun isn’t shining, and California has a goal of $100% clean electricity by 2045.
Inferno
Witness Eric Wesoff, who lives near Moss Landing, saw a 100-foot-tall inferno and orange fire lighting up the sky.
Experts say lithium battery fires can burn for hours or days.
When exposed to water, lithium batteries can explode and release toxic gases.
Vistra said no employees were injured, but Supervisor Kimberly De Serpa said she had heard from doctors about three people exposed to noxious fumes who went to the hospital for treatment.
The fire caught the attention of The New York Times, which reported
lithium-ion battery fires can emit toxic hydrogen fluoride gases.
Vistra Corp., based in Irving, Texas, is a Fortune 500 company that says it’s committed to a clean energy future by reducing greenhouse gases.
Vistra acquired the Moss Landing property, formerly home to a PG&E power plant when it purchased Dynegy in 2018 for $1.7 billion.
The Vistra plant capacity was 4,000 megawatt hours.
Assembly Member Dawn Addis (D-Morro Bay) wants an outside forensic investigation into what went wrong.
On Jan. 23, she proposed AB 303 to return permitting of such plants from state to local control.
Emergency Plan Required
Addis said she helped author Sen. John Laird’s SB 38, signed into law in October 2023, requiring battery storage plants to have “an emergency response and emergency action plan” and to coordinate with first response agencies and local emergency response agencies.
Watson said that plan was used.
Laird acknowledged the conflict between having clean energy of this type and everybody being safe.
Monterey County Supervisor Glenn Church called the fire “a Three Mile Island event for this industry,” saying renewable energy needs to be safe energy.
He endorsed an independent investigation, as did Gov. Newsom.
Supervisor Justin Cummings, who chairs the California Coastal Commission, predicted lithium battery plants would get a high level of scrutiny.
Vistra, which had proposed a lithium battery storage plant for Morro Bay when Dawn Addis was mayor, encountered opposition there. After four years of municipal review, but no permit, Vistra said it would ask the California Energy Commission to approve the project. That is allowed under AB 205.
This fire was the largest emergency response incident at Moss Landing power plant site in four years.
Battery packs overheated twice over a five-month period at the Vistra site between 2021 and 2022.
Vistra uses NMC batteries manufactured by South Korea’s LG Energy Solution, according to Canary Media.
In September 2022, the adjacent battery plant owned by Tesla and Pacific Gas & Electric caught fire but was quickly contained.
In May, the San Diego Fire-Rescue Department spent 14 days battling a hazardous fire that ignited at a lithium-ion battery storage facility in Otay Mesa. The fire emitted toxic gases and prompted nearby businesses to evacuate.
Perplexing Incidents
According to the U.S. Fire Administration, “battery fires have become one of the most challenging and perplexing incidents for the fire service in recent years.”
With lithium batteries used in cell phones, laptops, tablets, scooters, golf carts, electric vehicles, power tools and children’s toys, there have been at least 25,000 lithium-ion battery fires nationwide in the past five years, according to the U.S. Consumer Product Safety Commission, many of those in San Diego.
Bill Beecher talks to the Santa Cruz County Board of Supervisors about the Moss Landing battery storage fire at Tuesday’s meeting.
In 2023, recognizing concerns in the fire services, the Fire Safety Research Institute co-hosted a symposium on lithium ion battery technology, which is still online.
Patrick Durham, who spent 18 years in the fire service in Michigan before starting StacheD Training, a safety consulting firm, highlighted the Moss Landing plant fire in a video he posted.
Vistra’s Watson said the Moss Landing battery plant met all standards at the time it was built in 2020 but Durham said the plant design is not set up to prevent fire from spreading.
Durham’s explanation:
The site has multiple racks of batteries. Each rack contains multiple battery modules, and when one module fails, a single cell fails inside and can lead to a catastrophic event.
In a warehouse setup like this, there’s little to prevent fire from spreading through the entire facility.
The Tesla plan has a different design:
Tesla mega pack is self-contained designed to isolate failures, there are igniters to safely burn off flammable gases reduce the risk of explosion, and the units are spaced out, so a fire in one unit does not spread to next unit.
The Vistra plant was built in phases, Phase 1, two stories, 1,200 megawatt hours in 2020; then Phase 2, a single-story facility, 400 megawatt hours, and Phase 3, with 1,400 megawatt hours in 2023.
The fire occurred in the Phase 1 facility.
An adjacent battery plant, with 730 megawatt hours, was built by Tesla in 2022 and is operated by PG&E.
Previous problems at Vistra, according to Durham:
Sept. 2021, overheating led to a shutdown, problems with cooling
Feb. 2022, overheating led to shutdown and visible damage
2021, programming error led to unintended water release, short circuits and damage to multiple racks.
Minto Road Proposal
Santa Cruz County has not approved any lithium battery energy storage systems.
New Leaf Energy, founded in 2022 and based in Lowell, Mass., has proposed one BESS at 90 Minto Road, using newer technology. The site is surrounded by ag fields, and is near Pinto Lake City Park, College Lake, Amesti Elementary School and Monte Vista Christian School.
Max Christian, project lead for New Leaf Energy, answered questions via email.
“Our understanding is that the County has eliminated all other locations due to siting issues,” he said.
Battery storage technology is a continuously evolving technology, he pointed out.
“What happened at Moss Landing is awful and should never happen again,” he added. “The best way we can ensure that is to move away from the old generation of BESS, which is what they had at Moss Landing, in favor of the new generation of BESS that fully addresses the risks we see in the old technology that was deployed at Moss Landing. Among the new generation of BESS facilities in California, there have been no reports of fire.”
Christian described the proposed Seahawk battery storage this way.
“Batteries will be safely housed in purpose-built, sealed, steel containers that will feature on-board, 24/7 heat monitoring systems and specialized fire suppression systems. Each container will be physically separated by a buffer zone of several feet consistent with the most updated California Fire Codes for energy storage systems.
The Seahawk approach stands in stark contrast to the Moss Landing Vistra facility, which utilized a repurposed warehouse in which the batteries were located in open-air and not kept in separated containers.”
He added, “The batteries planned for Seahawk will utilize lithium phosphate (LFP) chemistry, which is more stable than batteries that use nickel-manganese-cobalt (NMC) chemistry. NMC chemistry, originally developed for electric vehicles and used at the Moss Landing Vistra facility, is more volatile and prone to fire. LFP chemistry, designed for stationary uses, is more secure.”
He maintained the Minto Road plant would not experience the catastrophic smoke plume seen at Moss Landing that resulted from a large building on fire that contained open-air batteries that were not kept in separated sealed containers.
Christian said the Seahawk project is being planned in collaboration with the Pajaro Valley Fire Protection District and CalFire,.
Times Publishing Group, Inc. called the Pajaro Valley Fire District and was told firefighters are just learning about Minto Road battery storage proposal. n
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Fire Photos Courtesy of Alekz Londos