Zurich PV rooftop whitepaper signals significant change

As the impacts of climate change continue to escalate, more and more companies are exploring options for sustainable energy, including solar-powered photovoltaic (PV) systems. But for some, dramatic news footage of rooftop fires associated with this technology has been enough to dissuade them from taking the renewable energy plunge.

Due to the frequency of fires associated with rooftop PV systems, Zurich initially took a conservative approach to the technology, said Rich Gallagher, VP Property Technical Director for Zurich North America. Gallagher, who is a globally recognized fire safety expert, has spent his 46-year career focused on finding ways to prevent fire. “This conservative approach left customers having to decide between implementing clean energy or having a favorable risk profile,” he said.

But a recent white paper from Zurich may be good news for companies interested in adopting PV technology. A joint effort between Zurich Insurance Group and Zurich North America, Photovoltaic (PV) Systems on Buildings: Pre-design, Design, Installation and Operation, has been seven years in the making and is the culmination of learnings gained by Zurich risk engineers and claims team members over time.

According to Gallagher, the whitepaper is considered a “gamechanger” in the industry for its updated guidelines, which present a new, risk-based underwriting approach meant to reduce the likelihood and severity of fires. Two key learnings informed the updated guidelines, said Gallagher, specifically:

• the severity of rooftop PV fires is driven by the type of roof under the system. Where a PV system is placed on a favorable roof, the public fire service should be able to confine a fire to a portion of a roof, and
• the frequency of rooftop PV fires can be reduced through installation quality, maintenance and fault monitoring.

“In many cases, the public fire service has used a lot of water as they confine a rooftop PV fire to a section of roof, but as the fire has damaged the roof’s cover, much of the firefighting water flows down into the building below,” Gallagher said. “We have seen cases where the building’s interior under the fire looks like a rain forest, with water dripping down from the roof above.” Water damage may interrupt the affected area for an extended period, as the building, contents and stock are repaired or replaced.

But the big concern is the unfavorable roof, according to Gallagher, such as those with polystyrene insulation or a wood deck and no thermal barrier. In these cases, the rooftop PV fire may spread into the building below. If fixed fire protection is not provided or is overwhelmed, the building may be lost to fire.

Zurich Claims has hired experts to assess fire-damaged PV systems, and the experts can readily identify quality issues that may have caused the fire—improper connectors, improper grounding, even connectors that had been recalled by the manufacturer for their tendency to crack. Gallagher recommends having a qualified independent third-party evaluate each rooftop PV system so potential issues may be identified before a fire.

“By applying the guidance in our white paper, our customers will be able to install rooftop PV systems that have no adverse impact on our view of their location,” Gallagher said, “which is a win for everyone.”