Solar power fire risk

Government figures confirm that the use of solar PV to generate electricity in the UK has grown rapidly since 2010 and there are now over one million solar PV installations in the UK.[1]

There are a wide range of issues when fighting fires involving PV systems. If solar panels are exposed to light, they will continue to produce potentially lethal amounts of direct current (DC) electricity, even if elsewhere in the building the electricity has been isolated. In practice, this means anyone operating near a solar panel system during daylight hours is effectively engaging with live electrical equipment.

Parts of the system are always live while light falls on the panels, even artificial lighting may generate small currents. The only way to stop the PV panels generating electricity even after they have been isolated, is to block out the light. In the US portable covers are being trialled, while in the UK London Fire Brigade has successfully trialled a black liquid polymer film that is discharged from a standard 9-litre cylinder, or fire extinguisher which can be used to seal the units to stop them generating energy from sunlight.?[2]

Jim Foran, who has pioneered award winning solar PV safety solutions in Australia and the UK[3]?and demonstrated their use at previous IFE international conferences, explains: “Once solar panels are up, they don’t make any noise, they are out of out of sight and out of mind. When it comes to causes of fires in solar panels it can be something as simple as a branch falling on the roof that then cracks the panels. Those cracks become hotspots which then become arcs, which then become fires. It can be vermin, rats and birds pulling or chewing at the wiring. But globally, poor installation or poor-quality componentry is the biggest factor. For example, in Australia around 1 in 5 installations inspected has issues.[4]”

Another potential risk to firefighters is the properties of the panels themselves. Sandwiched between the protective glass, frame and back sheet of the solar panel, solar cells present no risk to health, but once a panel burns and the solar cells are exposed, the burning panels can be highly toxic and dangerous to humans, so precautions are essential.

Increasingly, solar PV installations are both connected to the grid so that building owners can earn feed in tariffs if they export their excess energy or being installed with the option of battery storage where this excess energy can be stored in the building for future use.

They will be mounted within garages next to normal household possessions, next to parked cars many of which will have similar battery storage systems as well. They will not always be easily accessible and the risks of lithium-ion batteries from a fire safety perspective, especially have been well-documented.?

The implications of on-site solar PV generation for fire and emergency services personnel are significant and as part of its sustainability strategy, the IFE is building the knowledge base of fire safety challenges arising from new technologies and materials driven by sustainability to enable global knowledge sharing and development of best practice.

[1]?Review of solar PV capacity publications: Energy Trends, March 2022

[2]?Brigade trials light blocking solution for solar panel fires | London Fire Brigade (london-fire.gov.uk)

[3]?https://www.pvstop.com.au/

[4]?Clean Energy Regular: Small scale renewable energy scheme inspections