4 FM quick reads on photovoltaic
1. Rooftop PV Hazards and Best Practices Report
Solar panel installation on commercial facility rooftops is gaining ground for a variety of reasons. However, the pace of adoption has outpaced the code's and standard's ability to fully address this application. A report recently released by The Fire Protection Research Foundation compiles available information on the potential hazards created by rooftop photovoltaic (PV) installations and recommends best practices to ensure the safety of the facility while pursuing the energy-saving technology.
The report, "Commercial Roof-Mounted Photovoltaic System Installation Best Practices Review and All Hazard Assessment," addresses the following hazards: structural loading, wind loads, hail, snow, debris accumulation, seismic, fire (panel flammability, impact on roof fire ratings), and electrical hazards affecting fire fighting operations. The report addresses each hazard type in turn, and provides suggested best practices for mitigating each. For example, seismic risk can be addressed through strategies called out in a draft document from the Structural Engineers Association of California — "Structural Seismic Requirements and Commentary for Rooftop Solar Photovoltaic Arrays" (SEAOC Report PV1-2012).
The Foundation report also provides an overview of fires at facilities where the rooftop PV system may have been involved, such as the May 2013 fire that occurred at Organic Valley's corporate headquarters in La Farge, Wis.
In addition to spelling out the known hazards created by installing a rooftop PV system on a facility and best practices for addressing these, the report calls out the existing gaps in knowledge when it comes to these systems and fire safety. For example, "little is known about the causes of an incident, e.g. failure in the panel, wiring, or attachment method and about factors contributing to fire spread during an incident."
The report is available for free at the Foundation website. Download here.