Is Solar a Fire Risk?
A factor that is commonly overlooked in the debate on rooftop domestic solar PV systems is fire safety. To be fair, this is because, if properly installed, the fire risk from rooftop PV is negligible! However, in the interests of thoroughness, it’s probably a good idea to examine how rooftop PV could constitute a fire risk, and possibly other risks such as electrocution, and what measures are commonly taken to mitigate this risk. In the last decade, there have been a few incidences of rooftop solar PV installations either directly causing, or contributing to, domestic or commercial fires, so all the more reason to examine it.
So what fire risks could solar PV pose? Broadly these can be broken down into electrical fire risks, and heat-related fire risks. PV panels themselves at a domestic level generally output their electricity at around 30 to 60 volts, DC. In a relatively large domestic installation, this can quickly add up to 1.5 kilovolts or more, which, considering your mains is running at 240 volts (AC), is a fair amount! Should there be any faults with the equipment on the AC or DC side of the solar panel circuitry, this has the potential to cause electrical failure, and poses a fire risk. Solar panels also have the potential to get very hot while in operation, particularly on sunny days. This heat is generally not enough to set most inflammable materials that are likely to be on a domestic roof on fire, however, in edge cases, this could pose a risk
So what can be done to mitigate the fire risks set out above? Firstly, and this cannot be emphasised enough, use a proper, registered and accredited installer with proper regulated equipment. One of the most high profile solar panel fire cases in the domestic sector in the UK was caused by a faulty inverter, which shouldn’t have failed within the three years that the system had been operating. If everything in the system is installed to standard, is maintained well by registered maintenance professionals and is looked after, the fire risk of a typical domestic PV installation is effectively zero. The risk from solar panel heat is negligible as well: during the research for this piece, no cases were found where this was a contributing factor, and the limited few that were found were all electrical fires.
So where does this leave us? The prospect of a fire in one’s home is terrifying, but using the few, avoidable cases that have occurred to refute domestic PV as a solution more widely is nothing short of fearmongering. Nothing is free of risk, but with proper precautions, and professional installation, the fire risk from PV is negligible at wors