Solar Panel Fire Safety: Key Facts, Risks, and How to Stay Safe

Solar energy remains a safe and reliable technology when systems are properly designed, installed and maintained. However, recent UK fire data shows a clear rise in solar-related fire incidents, underlining the importance of proper installation and up-to-date safety measures.

What the Latest UK Data Reveals

According to analysis by insurer QBE, UK fire services attended 171 solar-related fires in 2024, compared with 107 incidents in 2022.

This equates to roughly one solar-related fire every two days, even though rooftop solar installations increased by only 29.6% over the same period. Of these incidents, 97 occurred in domestic homes.

Adrian Simmonds, Property Risk Solutions Practice Leader at QBE, commented:

“The pace of rollouts is exposing weak spots in safety and training.”

He noted that most fires in 2024 began in the inverter or the panel itself, particularly where components were installed in cramped or poorly ventilated spaces, such as lofts.

These components can overheat if installation, ventilation, or maintenance is inadequate.

Common Causes of Solar Panel Fires

The most common causes identified across UK incidents include:

1. Failures in DC Connectors

Poor DC connections can degrade over time, leading to electrical arcing. This arcing acts like a welding torch and can ignite nearby combustible materials such as timber battens, roof membranes, or insulation.

Typical causes include:

  • Poorly crimped joints
  • Connectors from different manufacturers being cross-mated
  • Incomplete insertion that fails to lock
  • Connectors assembled while wet

The most effective prevention is ensuring all DC connections are correctly made and kept away from combustible materials, either externally on the roof or enclosed within an arc containment system.

In-roof (BIPV) systems require particular care, as cabling runs close to building materials.

2. Loft Installations of Inverters

Inverters are a common source of ignition when installed in dusty or cluttered lofts with limited ventilation. Where a loft installation is unavoidable, fitting a smoke detector provides early warning and significantly reduces the risk.

Inverters are often better suited to:

  • Garages
  • Utility spaces
  • Walls made of solid brick or block

3.Battery-Related Risks

Cheaper lithium battery systems carry a higher fire risk if poorly manufactured or incorrectly installed. Batteries store a large amount of energy, and once ignited, fires are extremely difficult to extinguish.

For this reason:

  • Batteries should never be installed in lofts or living spaces
  • They should be mounted outside the home
  • They must be housed in a metal cabinet or fire-resistant enclosure

An emerging alternative is sodium-based batteries, which have a naturally lower fire risk.

4. Older Systems Lacking Modern Safety Features

Older installations may not include:

  • Modern residual current devices (RCDs)
  • Surge protection
  • Arc-fault containment
  • Rapid isolation switches

These systems should be inspected by a qualified electrician and upgraded if necessary.

Key Safety Measures to Consider

Three Safety Devices That Can Significantly Reduce Fire Risk:

A. Arc Container (ArcBox)

Safely contains electrical arcs from DC connectors near combustible materials, reducing fire risk.

B. Smoke Detection

Install a smoke detector wherever inverters or batteries are indoors. Test it annually and replace the batteries as required to ensure it works.

C. Firefighter Safety Switch (Rapid Shutdown)

Allows the system to be quickly isolated in situations where it cannot be easily shut down during a fire, ensuring safety for occupants and emergency services.

Key Takeaways

  • Fires linked to solar panels in the UK have tripled in recent years.
  • Most incidents are caused by poor installations, not the technology itself.
  • Keep DC connections clear of flammable materials.
  • Install smoke detectors for inverters located in lofts.
  • Never store batteries in lofts.
  • Use arc containment, fire barriers, and rapid shutdown switches to greatly reduce risk.
  • Have systems professionally checked after 1 year, and then every 5 years.

Our Approach to Solar Safety

We install all the safety features required for each system and can upgrade older installations to meet modern fire safety standards.
With the right design, professional installation, and regular maintenance, solar energy remains a safe and reliable solution for homes and businesses for many years.

Sources