Fire at PG&E's Moss Landing battery plant causes Highway 1 closure, shelter-in-place order

Road closures are in effect and a shelter-in-place order is coming as a battery pack smolders in PG&E's Moss Landing Tesla battery plant. 

A fire at Elkhorn Battery was first reported to the North Monterey County Fire Protection District District around 2am Tuesday morning. Chief Joel Mendoza reports that firefighters first to the scene found a battery pack on fire. Fortunately, he adds, it burned quickly and relatively cleanly.

"The thing about these batteries is they burn for days, sometimes," Mendoza says. "In this particular case it burned rather quickly, in six hours or so."

As of about 9am, Mendoza adds, "We don't have any flame coming out of it. We're going to continue to see smoke; it's white smoke, not black dirty smoke."

Fire District officials immediately notified the few residential neighbors (about seven or eight) in the immediate vicinity of the battery plant. But even as the fire calmed down, the wind direction began to shift, prompting officials to expand the safety footprint outward.

Before rush hour peaked, by 7:30am, Highway 1 was closed between Jensen Road to the north, and Molera Road to the south. According to a CHP incident description, the first fire report to that agency came in at 5:11am, three hours after firefighters first responded to the plant. 

As of 7:30am Tuesday morning, CHP was estimating that a reopening for Highway 1 was four to six hours away, by 11:30am the earliest. Dolan Road is also closed between Highway 1 to the west and Via Tanques Road to the east. (That does still allow for north/south traffic on Castroville Boulevard.) 

UPDATE: Officials reopened roads and lifted all orders just before 7pm on Tuesday.

Mendoza says that due to wind conditions and the potential for inhaling dangerous combusted material in smoke, his department is issuing a shelter-in-place order for people in the closure area along Highway 1, and about two miles east along Dolan Road to Via Tanques Road. 

"As we started seeing weather and wind speed and direction change, we decided we would shut down Highway 1 and Dolan Road—we are not allowing anybody in," Mendoza says. "A shelter-in-place order is going out that is going to say stay indoors, shut you windows and turn off AC units.

"It's out of an abundance of caution. If some of these products of combustion  carry far enough to where somebody would inhale something—we don't anticipate that happening, but as a public agency in charge of public safety, we [are acting in] an abundance of caution."

The impacted facility, PG&E's Elkhorn Battery, went into operation on April 18 of this year. The 182.5-megawatt Tesla Megapack battery energy storage system enables PG&E to incorporate more renewable sources into its energy portfolio. 

The plant features 256 Tesla battery units on 33 concrete slabs. It's one of the largest utility-owned, lithium-ion battery energy storage systems in the world.

The plant was designed and constructed jointly by PG&E and Tesla, and is maintained by both companies; PG&E owns the facility. PG&E's media relations team did not immediately respond to a request for comment on Tuesday morning.

The impacted facility is smaller than the 400-megawatt Vistra battery storage facility next door, which a spokesperson says is not impacted by the fire today. 

A fire alarm response at the Vistra plant last fall was ultimately determined not to be from a lithium ion battery, but an overly sensitive alarm system triggered by smoke. 

Editor's note: This story has been updated to reflect the following correction. A fire department response last September at Vistra was due to smoke, and no fire was every discovered. A subsequent investigation revealed it was due to smoke, and not from lithium ion batteries.