Solar panel fire risks 2026: what homeowners need to know
More than five million UK and US homes now generate solar power. As the installed base grows, so do the fires — most starting not in the panels themselves but in inverters, connectors, and DC cabling. Here is what causes them and how to reduce your risk.
600–1,000 V
Typical DC voltage in rooftop panel cabling — remains live even after mains isolation, because panels generate power from any available light
Risk reduction
6 steps to reduce solar fire risk
Use an MCS-accredited installer
In the UK, require MCS certification and a system that meets BS 7671. In the US, use a NABCEP-certified installer and verify local permit requirements. A poor installation is the root cause of most solar fires.
Inspect DC cabling and connectors
MC4 connectors and DC cable terminations should be inspected every three to five years by a qualified installer. Loose or corroded connectors cause arc faults — the primary ignition source in solar fires.
Install arc fault detection (AFCI)
Modern inverters with built-in AFCI and rapid shutdown capability are significantly safer. Rapid shutdown cuts DC voltage to safe levels within 30 seconds of mains isolation, protecting firefighters.
Label your system for emergency services
Install NFCC/NFPA-compliant warning labels at the consumer unit, meter box, and roof entry points. Include inverter location. This allows firefighters to assess the hazard quickly on arrival.
Keep inverter area clear and ventilated
Inverters generate heat and must not be boxed in or covered with stored items. A cluttered utility room around the inverter dramatically increases fire spread risk if the inverter overheats.
If you have battery storage, treat it separately
Lithium-ion home batteries (Tesla Powerwall, Sonnen, etc.) have distinct fire and thermal runaway risks. Follow manufacturer siting requirements; most specify minimum clearances from living spaces and combustible materials.
Where solar fires actually start
The panels themselves rarely ignite. Modern solar panels are manufactured to IEC 61730 safety standards and are inherently resistant to ignition. The fire risk in a solar PV system sits primarily in three places: the inverter (which converts DC to AC and contains significant electronics), the DC isolators and junction boxes (mechanical switching components prone to arcing if corroded or loose), and the DC cabling between the roof and the inverter (where insulation damage or faulty MC4 connector crimping causes arc faults). A UK Home Office study of solar-related insurance claims found over 60% of incidents originated at the DC isolator or inverter — not the roof array.
Why solar fires are different to extinguish
The hazard that distinguishes solar fires from ordinary electrical fires is the persistence of the DC supply. When firefighters isolate a building's mains electricity, they expect the electrical hazard to cease. With solar, the cabling between the panels and the inverter continues to carry high-voltage DC as long as light falls on the panels — including diffuse daylight and even artificial light at night. This means direct water attack on roof panels by firefighters risks electrocution. The National Fire Chiefs Council (NFCC) guidance is to treat a solar fire as a live electrical fire, maintain safe working distances, use CO2 or dry powder on accessible components, and let the roof fire burn while preventing spread where possible.
Tell the fire service immediately
If you call 999 or 911 for a fire at a solar-equipped property, tell the dispatcher that solar panels are installed and whether a battery storage system is present. This information is passed to the attending crew before arrival and changes their approach. Install warning labels at your meter/consumer unit and building entrance — this saves critical seconds on arrival.
Home battery storage: an added dimension
Home battery systems (primarily lithium-ion chemistry) introduce thermal runaway risk — the same hazard profile as e-bike and e-scooter batteries. A lithium battery fire releases toxic gases, is extremely difficult to extinguish, and can reignite hours after apparent suppression. Follow manufacturer siting requirements precisely; most specify minimum 30 cm clearance from combustibles, prohibition in sleeping areas, and adequate ventilation. Ensure your home has working smoke alarms outside the battery room — see our smoke alarm placement guide for positioning near utility rooms.
Getting your system checked
Solar PV systems are not covered by standard annual electrical inspections (EICR) because they sit on the DC side. Arrange a dedicated solar health check — most MCS-accredited installers offer one — every three to five years, or immediately if you notice: flickering output readings, a burning smell near the inverter, any visible damage to roof cabling, or if your system predates 2015 (older DC isolators are a known failure point). If you are buying a property with an existing solar installation, request the installation certificate and inspection history before exchange. For broader electrical fire prevention, see our electrical fire prevention guide.
Sources: NFCC Solar PV Guidance · IET BS 7671 · NFPA 855 (Energy Storage)
Solar FAQ
Questions about solar panel fire risks
Solar panel fires remain relatively rare compared to other electrical fire causes — the UK's Fire and Rescue Service data indicates a small but rising number of incidents as adoption grows. Most fires originate not in the panels themselves but in the inverter, DC isolator, or wiring connections. A 2023 analysis by the Fire Protection Association found arc faults in DC cabling to be the most common root cause. As the installed base grows — over 1.3 million UK homes and 3.6 million US homes now have solar — the absolute number of incidents is rising even if the rate per installation is low.
Solar panels generate DC electricity whenever there is light — including from emergency lighting and streetlights. Unlike AC mains, which can be isolated at the consumer unit, the DC cable between the panels and the inverter remains live at potentially 600–1,000 V even with the mains isolated. This creates a risk of electric shock for firefighters. For this reason, the fire service approach for solar panel fires typically involves defensive firefighting from a safe distance, allowing the fire to burn while protecting exposures, rather than direct attack. Always inform the fire service immediately that solar panels are installed — a fact that should be marked on your consumer unit or a label at the main entrance for emergency services. For broader electrical fire prevention, see our electrical fire prevention guide.
In the UK, solar PV systems connected to the grid must be installed by a Microgeneration Certification Scheme (MCS)-accredited installer. Self-installation is not prohibited for off-grid systems, but the DC wiring between panels and inverter, and particularly the rooftop installation, must be carried out to BS 7671 (IET Wiring Regulations) and building regulations. In practice, grid-connected DIY installations are illegal without NAPIT or NICEIC certification. In the US, local building codes and utility interconnection agreements apply; most require a licensed electrician for the AC side at minimum.
Inform the attending crew immediately that solar panels are installed, their location (roof section), whether a battery storage system is present, and where the inverter and DC isolators are. In the UK, the National Fire Chiefs Council (NFCC) recommends installing a PV isolator warning sign at the consumer unit and at building entry points. For battery storage systems (especially lithium-ion home batteries), also identify the battery location — thermal runaway in a home battery presents a significantly different hazard than a rooftop panel fire. See also our e-bike battery fire risks guide for thermal runaway background.