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Battery storageUnited StatesEIR-0100

Battery fire at Bolster Substation in Peoria, Arizona contained by controlled burn

Oct 2025Published 7 Sept 2026Responsible editor: Chief Editor

SignificantThermal / fire25 MW
Estimated damageEstimated by the register's adjusterHow? Know the real figure?
Figure hidden: shown to subscribersMedium confidence
out of service for about •• daysShown in the record →Full estimate
From the recordRoot cause hiddenAsset hidden years oldThe maker is named in 13 other entries (being named is not a finding of fault)
Where
Bolster Substation Battery, Peoria, Arizona
Operator
Salt River Project
What
Fire in one battery storage container
Injuries
None reported
Cause
Not reported

Companies named in the reporting of this entry (being named is not a finding of fault): Salt River Project, Tesla

What happened

A fire broke out in the evening at the Bolster Substation Battery, a battery storage facility located at a Salt River Project substation in Peoria, Arizona. Flames were visible coming from one of several battery storage containers. Multiple fire departments responded and worked to contain the blaze. Crews used water to cool adjacent battery units while allowing the fire in the affected unit to burn out under controlled conditions, a standard approach for lithium ion battery fires where direct extinguishment is difficult.

The battery system, supplied by Tesla, was taken offline, though no customers lost power as a result of the incident. No injuries were reported. The cause of the fire had not been determined at the time of reporting. The system had been in service for approximately four years at the time of the incident.

Contributing factors

Not reported at the time of publication; cause of the fire was undetermined.

Lessons learned

  1. Multiple fire departments must coordinate at battery sites because several agencies responded to contain the blaze.
  2. Lithium ion battery fires need perimeter cooling and controlled burn out as direct extinguishment is difficult.
  3. Segment battery storage so one unit can be isolated without customer outages.

More lessons on fire suppression and firefighting, electrical protection and isolation, from every incident on the register.

Not yet known

  • Root cause of the fire
  • Battery model and exact age
  • Duration of downtime
  • Cost of damage and repairs

This entry is updated when these are reported. Get an alert for the next one like it.

Source

azfamily.com

Published 2026-09-07. Written from public reporting. Descriptive, not investigative. See the data accuracy disclaimer.

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Chart to reuse with this story: Battery storage incidents in the United States, by year, free with a credit (PNG).

Battery storage incidents in the United States: 49 entries, with a free alert for the next one.

Battery storage fires: the counts, the latest entries and a free alert for the next one. Also: battery storage container fires.

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