Research from global business insurer QBE reveals that solar panel fires are happening at more than twice the rate of installations. Fires were up 133% over four years to the end of 2025, while solar installations rose 52%.
QBE collected data through Freedom of Information requests made to 49 UK fire services in 2025 and in February 2026. Fire services attended 212 fires involving solar panels in 2025, more than double the 91 recorded in 2022.
In March 2026, installations surpassed two million for the first time. As of May 2026, there were 2,047,225 solar panel installations across the UK.
DC cabling and connectors were the leading cause of fires.
The frequency of fires spreading to the wider building has tripled.
Clean power plans
In 2025, there were 102 residential fires involving solar panels, 48 in commercial buildings, 14 in industrial buildings and 14 at solar farms.
“It is clear installation quality and fire safety are not keeping pace with the speed of deployment,” QBE risk manager Adrian Simmonds said.
QBE said the residential fires were a worry given that the Future Homes Standard mandates that all new homes must have onsite renewable energy generation from March 2028.
Solar panel fires at commercial properties rose sharply from 33 fires in 2024 to 48 in 2025, a 46% increase. While fewer in absolute numbers, industrial building fires jumped 133%, from six in 2024 to 14 in 2025.
The government’s Solar Roadmap puts more rooftop solar on warehouses, retail outlets and industrial buildings at the heart of its Clean Power 2030 mission.
Poor installation
DC cabling and connectors were the leading cause of fires in 2025, accounting for 49 fires, almost doubling from 26 in 2024.
Next came the solar panel itself (36), the battery bank (23) and the inverter (19).
“The rise in fires linked to DC cabling and connectors points directly to installation quality,” Simmonds said.
“Loose connections, damaged wires and faulty wiring lead to arc faults and other electrical failures. Every solar panel system, whether on a home, warehouse or solar farm, should be installed using MCS-accredited installers and consistently maintained.”
Lithium-ion risk
The rapid adoption of lithium-ion batteries in solar panels also concerns QBE. Such fires cause thermal runaway, a chemical reaction where batteries start to overheat irreversibly, usually due to impact damage, overcharging or overheating.
Thermal runaway ignites fires that spread faster and take longer to tackle, requiring up to 10 times more water to contain than a conventional fire.
UK fire brigades tackled a lithium-ion battery fire once every five hours in 2025, QBE research revealed. The insurer noted that as battery storage proliferates on solar installations, the risk of fast-spreading fires is likely to grow.
More frequent and more severe
Solar panel fires are not only becoming more frequent, but more severe. The number of fires spreading beyond the solar installation nearly tripled between 2022 and 2025, rising from 33 to 88.
Simmonds said installation location was critical. “Units placed in confined or hard-to-access spaces, combined with infrequent inspection, create the conditions for fires that are both more likely and harder to contain,” he said.
QBE recommends that homeowners and businesses:
- Use certified solar panel installers (MCS-accredited);
- Conduct annual inspections and clean solar panels to prevent overheating or debris buildup;
- Check that firefighter’s switches and arc-fault detection systems are correctly installed and accessible;
- Avoid mounting solar panels on combustible roofs or ensure proper separation and fire-resistant barriers;
- Pay particular attention to DC cabling and connector quality at commissioning and during annual service visits;
- Ensure battery storage units are installed in well-ventilated, unobstructed locations that remain accessible for inspection and emergency response;
- Inspect installations after extreme weather events such as high winds, hail or flooding.
Detailed recommendations for construction professionals, property owners and installers are available in QBE’s Solar Panel Installation Risk Management Guidance.
