Possible storm damage could have sparked Danbury roof-top solar panel fire

A roof-top solar panel array caught fire Thursday evening in southern Danbury, sending plumes of thick black smoke into the air that were visible for miles. A roof-top solar panel array caught fire Thursday evening in southern Danbury, sending plumes of thick black smoke into the air that were visible for miles. Photo: / Rob Fish Photo: / Rob Fish Image 1 of / 8 Caption Close Possible storm damage could have sparked Danbury roof-top solar panel fire 1 / 8 Back to Gallery

DANBURY — Storm damage could be to blame for a fire on a roof-top solar panel array that sent a column of thick, black smoke over southern Danbury on Thursday evening.

Firefighters from Danbury and Bethel battled the two-alarm fire for an hour before containing it to a relatively small portion of the panels in the array on top of a warehouse shared by Beacon Roofing Supply and Opportunity Buying at 2 Great Pasture Road, Danbury Fire spokesman James Gagliardo said.

The Danbury Fire Marshal’s Office is still investigating the cause of the fire and could not provide more details Friday afternoon.

But property manager Stuart Longman suggested high winds during storms this week could have damaged one of the 3,500 individual panels on top of 100,000-square-foot warehouse.

“The storms were very violent and there were some severe winds and it’s possible that the wind could have pushed one of the panels down on the racking which might have created an arc, but I’m speculating right now,” he said. “The system was in perfect shape, operating perfectly a few days ago, and the storms are all that’s happened since.”

Area solar experts say fires caused by solar panels are uncommon and new regulations help prevent them even further.

Only about 20 panels were damaged by the time the fire was contained and there was water damage inside the Opportunity Buying portion of the building because firefighters sprayed the fire from atop ladder trucks, Longman and Gagliardo said.

Danbury Fire’s new drone helped knock the fire down quickly, Gagliardo added. The drone hovered above the building to give firefighters a better view and its thermal imaging camera helped contain the fire faster, he said.

The array is shut off for now while crews assess the damage and work to remove the damaged panels, Longman said.

Some of the panels on the roof at 2 Great Pasture date back nearly a decade to when Longman received a $2.6 million federal stimulus grant to continue installing solar panels on buildings around the area.

That predates newer requirements that prevent arcing and require a system to shut down instantly if one is detected, said Dwayne Escola, a partner in the Ridgefield-based Northeast Smart Energy.

“If it were (direct current) wires, those are the ones up on the roof, and they were abrased somehow, it potentially can cause a fire,” he said. “It’s extremely rare. There was one big one, a fire in Bakersfield, California, that caused some of these changes.”

But businesses or homeowners with solar panels on their properties likely do not need to worry about their systems after the storm, leaders of Ross Solar and ConEdison Solutions said.

There are almost 28,000 residential solar panel systems in the state and thousands more commercial systems with almost no instances of a fire, said Stephan Hartmann, residential sales manager at Ross Solar.

“If an owner observes any loose wires or gets weird voltage readings on their data monitor, they can definitely call someone in and have it inspected,” he said. “But I’d hate for anybody to take away from this that there’s any reason for alarm.”

zach.murdock@hearstmediact.com