At 1:30 in the afternoon on March 15th, 2023, the Mahwah fire department was dispatched to a car dealership on Route 17 for an unusual report: the manager reported a section of the roof was visibly glowing and there was smoke inside the building.

The first Mahwah units arrived on scene and confirmed an active electrical fire in the roof decking of the structure, prompting Asst. Chief Rupert to call for the Working Fire assignment.

That is where the normal part of this call ended as firefighters got on the roof of the structure and discovered the entire roof was covered in solar panels. To make matters more complex, these were not new panels that are typically installed on racks above the roof, but an older panel design that was part of the physical roof material. And these panels were not even tied to the building but older panels that went out of use and were abandoned.

After confirming that the fire was being driven by arching wires from the solar array, firefighters set about trying to isolate the panels driving the fire and stop those from producing electricity so the fire could be extinguished safely. And since there are no switches or breakers on solar panels, the only sure-fire way to stop solar from making electricity is to cover the panels with tarps. LOTS of tarps.

What followed was approximately two hours of firefighters carefully dissecting the solar setup and covering large swaths of the roof decking with every tarp that could be found. We even sent units back to Mahwah firehouses to get all the tarps not yet on scene.

With enough time and the assistance of an electrician, the solar array driving the fire was eventually deenergized and firefighters safely extinguished the fire (which by this time had burned a basketball sized hole through the steel deck of the roof.)

As always, we sincerely appreciate the help of our mutual aid partners who arrived on scene with extra manpower and many tarps.