Photovoltaic solar panels and fires: what risks today?

Electricity self-consumption via the installation of solar panels on the roof has many advantages for private homes, but is this type of installation perfectly safe? This is the question we asked ourselves. Elements of response through several expert opinions.

Between the continuous rise in gas and electricity prices and the tension on fossil resources caused by the conflict in Ukraine, more than ever, the need for energy sovereignty is placed at the forefront in France. This is particularly true for households who can find in the installation of photovoltaic solar panels on the roof of their dwelling a recourse to self-supply electricity and thus become less dependent on “conventional” suppliers.

But is this operation 100% safe? According to figures from the National Observatory for Electrical Safety (ONSE), in 2021, between 20% and 35% of fires in homes were of electrical origin. If the precise cause of these outbreaks of fire is often not obvious to determine, it has been proven that in several cases, the solar panels are not foreign to it. We interviewed several professionals to find out more.

For Christel Ebner, Director of Observatory and Risk Assessment at AQC, "there are risks, given that this type of installation produces direct current electricity, which remains much more dangerous than alternating current. employed in the construction industry. Nevertheless , these risks remain to this day "difficult to quantify" according to David Gréau, General Delegate in charge of photovoltaics at Enerplan.

Where do the risks come from?

According to a study carried out in 2012 by the AQC, the losses noted on installations integrated into the roof came from “70% of sealing problems, 30% of electrical problems of which 10% degenerated into fire. “ Relatively old figures which have unfortunately not been updated to date by the agency.

What are the main risk factors for ignition of photovoltaic solar panels? They are threefold for Christel Ebner: “mainly, the design, implementation and maintenance” of the product .

On the design side, the AQC issued warnings about faulty manufacture of junction boxes (on the back of the panel) on several brands. The defects noted on the installation of the panels generally relate to incorrect installation of the connectors – the male and female connectors must be of the same brand, which is unfortunately not always respected – and connections. Finally, maintenance is paramount, as aging equipment can easily lead to malfunctions over time. The problem? To date, there are no regulations on the subject. Maintenance of photovoltaic solar panels is highly recommended, but not mandatory.

David Gréau, General Delegate in charge of photovoltaics at Enerplan, Syndicat de l'Energie Solaire Renouvelable, adds that risks can also come from the initial electrical network of the building on which the panels are installed. It is therefore up to the professional to make an in-depth inventory of the home before installing the solar panels.

More generally, claims occur most of the time in single-family homes where “unknowing people” live and who are poorly informed by certain unqualified companies.