Fire at SEPTA bus lot caused by previously explosive electric batteries.

A significant fire incident occurred on Thursday morning at SEPTA’s largest bus depot in Philadelphia, resulting in the destruction of 40 decommissioned buses. The blaze is suspected to have originated from a lithium-ion battery within a Proterra electric bus, as confirmed by a fire department spokesperson. The Fire Marshal’s Office has determined that the battery was the leading cause of the fire, although further inquiries have been directed to the transit authority for more detailed information.

The fire erupted around 6:15 a.m., coinciding with the start of the morning rush hour. Fortunately, there were no reported injuries, and the incident did not severely impact the flow of buses in operation at the time. Emergency responders, however, faced challenges in controlling the blaze due to the tightly packed arrangements of the decommissioned vehicles, necessitating the towing of several buses out of the way. Firefighters were also required to dismantle fences to facilitate access for firefighting equipment.

SEPTA General Manager Scott Sauer remarked on the necessity of relocating the Proterra buses following the incident, stating that the agency needs to mitigate the risk of another such occurrence. Sixteen of the destroyed buses were directly impacted by the fire. This is not the first time the agency has faced difficulties related to Proterra batteries; a similar incident occurred in November 2022 when a battery pack in an idle electric bus ignited at SEPTA’s Southern Bus Depot, leading to extended firefighting efforts and complications in the agency’s transition to a green fleet.

SEPTA acquired 25 battery-electric buses from Proterra in 2016, all of which have remained out of service since 2020 due to various issues, including chassis cracks and inadequate performance for the demands of urban transit routes. The company filed for Chapter 11 bankruptcy protection in August 2023, asserting that it was dealing with multiple lawsuits over its electric bus technology. Proterra’s transit bus division was subsequently sold to Phoenix Motorcars during bankruptcy proceedings. In September, the National Highway Traffic Safety Administration initiated recalls for two Proterra bus models following revelations that software malfunctions in the cooling system made the batteries susceptible to overheating.

The fire also prompted health advisory measures from the Philadelphia Department of Public Health, which urged local residents to remain indoors due to elevated levels of harmful pollutants detected in the smoke. Schools in the vicinity were advised to turn off their HVAC systems during the incident. By Friday morning, air quality monitoring indicated a return to normal levels, lifting the advisory.

This incident emphasizes ongoing safety concerns related to electric bus technology, particularly with regards to lithium-ion batteries, as transit authorities nationwide continue to explore sustainable options amid increasing regulatory pressure to reduce greenhouse gas emissions.