What is the real risk from solar panels? 

With recent reports of a domestic solar panel exploding on a roof at a West London council house, is a hidden danger lurking? How does this impact confidence and the growth of solar photovoltaic (PV) panels across both domestic and commercial sectors?  

Is solar power safe? Recent reports of a solar panel explosion in West London raise concerns. Richard Williams, an experienced engineer from Aztec Solar Energy Ltd, sheds light on the risks and safety measures.

Richard Williams is foremost an engineer, as well as the founder and managing director of Aztec Solar Energy Ltd, with over 30 years in the energy services sector. Here, he shares his views on safety issues facing the industry.  

Last year, primarily due to the energy price crisis and a sustainability drive, the solar power industry saw a significant jump in solar PV installations. According to data from the Microgeneration Certification Scheme (MCS) – the standards organisation for solar energy and heating – 130,596 solar panels were mounted on UK rooftops in 2022.  

Unregistered installations

This figure represented growth in one year, which was previously only experienced in the three years between 2019 and 2021 combined, except those years following subsidy changes. These figures include all solar PV systems with a generating capacity of up to 50 kilowatts registered with the MCS notably, therefore, the figure is likely to be even higher, with an increasing number of installations in the UK not registered at all. 

It does mean there are over 1.3 million registered solar power installations across the country, two-thirds on the ground and the remainder on residential and commercial roofs, generating at least 15GW of solar power in the UK. 

PV solar panels promise cost savings in energy bills and are described as clean and green electric energy. Seen in many a field and rooftops, the growth of solar PV panels has been significant and is changing the energy landscape. 

But what controls are in place, and who is monitoring safety? 

Some may be shocked that PV installers are not legally bound to follow the guidelines or obtain accreditations from certifying organisations such as the MCS. 

The big issue is that anyone can install a solar panel in the UK. Yes, work must be cleared by the local council and the government ‘recommends’ the use of a registered electrician, but it’s not necessary by law.  

As with all electrical installations, electrical incidents may happen, so all electricians are qualified and must undertake regular competency training and ongoing refresher training. Arc faults and faulty wiring can cause solar panels to catch fire, and the risk of a solar panel catching fire is very low, but it is not zero.  

Solar panel fires can be caused by improper installation or maintenance, and by damage from extreme weather events, such as hail or lightning. Higher voltages can be prone to arcing and is a known common cause of fires. Still, installing microinverters connected to the panel to convert the output to a safer level considerably reduces the risks. Like maintaining your car, checks must be done regularly on all PV installations, as does using reputable and registered PV installers. PV panels are often forgotten about and left to deteriorate, and with those systems come risks, as with any neglected equipment. 

Greater reduction in fire risks

It’s important to be up to date with the latest safety recommendations and regulations, and as with all things new, products evolve. Technologies continue to develop, and with that have come new solar panels that are more resilient and offer an even greater reduction in fire risks. Understanding these products and their installation comes from experience, working in an evolving sector, and with experts who can recommend the most appropriate panels and systems.  

The first step would simply be to ensure those installing your PV system and/or battery storage are registered with the MCS and have been installed in accordance with IET guidance. This will verify the competence of the installer, and the installer is duty-bound to use verified products, ensuring safety and quality. 

Anyone concerned about their PV systems should seek further advice and consider retrofitting a micro inverter AC system or module-level optimisation. Look at the maintenance programme and ensure the system has been checked through periodic testing and by a professional. If you are worried and suspect signs of overheating, isolate the supply and call the installer.  

As with all technologies that have been installed effectively and are maintained and managed, be assured solar PV panels will deliver clean, cost-effective power safetly.