Greeley Fire Investigators Found No Evidence the EV Battery Caused Garage Fire, CBS Reports

CBS Colorado reported, citing the Greeley Fire Department, that investigators found no evidence the electric vehicle or its high-voltage battery caused or contributed to a Sept. 2 garage fire in Greeley, Colorado.¹ According to CBS, investigators classified the fire as accidental and attributed it more broadly to an electrical failure involving equipment used to power the EV charger.¹

That distinction matters because the report does not establish that the extension cord itself failed.

CBS says investigators located the fire's origin inside the attached garage near a 240-volt wall outlet and an extension cord being used to power the EV charger.¹ But the report does not identify whether the failed component was the outlet, the cord, the charging equipment, branch wiring or another part of the electrical supply path. Treating extension cord near the origin as extension cord caused the fire would go beyond the reported finding.¹

The public City of Greeley pages reviewed Sept. 5 did not expose an incident-specific fire report or release with the finding. The city's Fire Prevention page says the bureau performs fire investigations and incident-report review, but it does not discuss this fire.² For that reason, the incident-specific findings here remain attributed to CBS's account of what the Greeley Fire Department reported.

What current charging guidance says about extension cords

The Greeley incident does not establish a universal rule for every charging product, but several current safety sources give direct guidance for the equipment and use cases they cover.

Chevrolet's current U.S. home-charging instructions tell owners not to use extension cords for either Level 1 or Level 2 charging when connecting charging equipment to the wall outlet.³ The page also warns against multi-outlet strips, splitters, grounding adapters and surge protectors in that connection.³

Tesla's North American Corded Mobile Connector manual likewise warns users not to plug that product in through an extension cord, power strip or multi-outlet adapter.⁴ That is product-specific Tesla guidance; there is no evidence in the reviewed sources that Tesla equipment or a Tesla vehicle was involved in the Greeley fire.

The Electrical Safety Foundation International takes a broader consumer-safety position, advising against extension-cord EV charging and recommending that owners follow manufacturer instructions, use certified charging equipment and have electrical work assessed by a qualified electrician.⁵

Those instructions are useful owner guidance, but they are separate from the Greeley cause evidence. The reviewed incident reporting does not identify the vehicle or EVSE brand, the extension cord's rating or condition, the charging current, or a code violation. It also does not establish a charger defect, manufacturer responsibility or a broader EV fire-rate pattern.¹

For owners whose charging cable cannot reach, the evidence-backed answer is to start with the connection method approved by the specific vehicle and charging-equipment manufacturer rather than assuming a generic extension-cord specification is acceptable.³⁴⁵

Sources

Footnotes

1. CBS Colorado — “Northern Colorado investigators say house fire began near outlet used to power electric vehicle charger,” updated Sept. 4, 2026. https://www.cbsnews.com/colorado/news/northern-colorado-investigators-house-fire-outlet-extension-cord-power-electric-vehicle/ Originating local report for the incident; attributes the origin, accidental classification and electrical-failure finding to the Greeley Fire Department. The report does not identify the exact failed component. ↩ ↩² ↩³ ↩⁴ ↩⁵

2. City of Greeley — Fire Prevention. https://greeleyco.gov/fire/fire-prevention-bureau/fire-prevention/ Current city page establishing that the Fire Prevention Bureau performs fire investigations and incident-report review. It does not establish the facts or cause of the Sept. 2 incident. ↩

3. Chevrolet — How to charge your EV at home. https://www.chevrolet.com/support/vehicle/ev-charging/home-charging/how-to Current Chevrolet U.S. home-charging guidance. It says not to use extension cords or several other intermediary devices between the wall outlet and charging equipment; it is not evidence about the Greeley fire. ↩ ↩² ↩³

4. Tesla — Corded Mobile Connector Owner's Manual, North America. https://www.tesla.com/sites/default/files/pdfs/NA_Corded_Mobile_Connector_Owners_Manual.pdf Product-specific safety manual warning against use of an extension cord, power strip or multi-outlet adapter with the Corded Mobile Connector. It does not establish that Tesla equipment was involved in the Greeley incident. ↩ ↩²

5. Electrical Safety Foundation International — Prepare your Home or Business for Electric Vehicles. https://www.esfi.org/prepare-your-home-or-business-for-electric-vehicles/ Current nonprofit electrical-safety guidance advising against extension-cord EV charging and recommending manufacturer instructions, certified equipment and qualified electrical assessment. It is not incident-specific evidence. ↩ ↩²