As solar panels become more popular amongst an increasingly energy-conscious industry and market, Scott Williams, of Clarke Williams, explains the fire safety concerns we should be aware of
Solar panel installations have become a popular solution for generating renewable energy, both for residential and commercial properties. While solar panels offer significant environmental and cost benefits, they also present certain risks, particularly related to fire safety. Understanding these risks is crucial for property owners, installers, and insurers alike.
This guide explores the potential fire hazards associated with photovoltaic (PV) systems, the impact of various installation factors, maintenance recommendations, and the importance of complying with industry standards.
By addressing these concerns, property owners can ensure the safe operation of their solar installations and mitigate the risks that may arise over time.
What are the costs of solar panel installations?
The cost of installing solar panels varies greatly depending on several factors, such as:
- Number of panels
- Type and height of the roof
- Number of inverters and other components
- Capacity of the system
For a typical system, including installation, the cost generally falls within the range of several thousand pounds. Systems that include battery storage are more expensive and may be significantly higher.
Understanding solar panel fire-related claims
Quantifying the number of fire-related claims caused by solar panels is difficult because:
- UK Fire & Rescue Services do not have a specific category for fires caused by photovoltaic (PV) systems.
- Insurance claims often log the cause of fire without specifying if a PV system was involved.
Thus, there is no reliable data directly linking PV systems to fire losses.
Combustible roofs and solar panel installations
Solar panels should not be installed on roofs classified as combustible, particularly those with combustible insulation. The system can serve as both an ignition source and a fuel source due to the plastic components. Even if the roof has a non-combustible metal surface, the insulation underneath could present a fire risk.
If LPS 1181 or FM-approved panels are installed, their fire resistance is typically tested without solar panels on top. When installed with solar panels, the roof panels must be treated as combustible due to the potential increased fire risk.
Compliance with British Standards
PV installations must comply with British Standard BS 7671, which governs electrical installations, but there is no British Standard specifically for PV systems. Property owners should review their fire risk assessments to account for the hazards and risks associated with roof-mounted solar panels.
Thermographic inspections
Thermographic inspections of PV systems can be useful in identifying potential issues. The frequency of inspections varies:
- If there are ongoing issues, inspections may need to be frequent.
- As part of a preventive maintenance regime, inspections every few years are generally recommended.
Legislation on solar panel inspections
PV systems fall under BS 7671, with BS EN 62446-2 covering the inspection and maintenance of these systems. While there is no set inspection frequency, Solar Energy UK and MCS provide best practice guidelines based on system capacity.
Risk improvements for solar panel systems
Common risk improvements include:
- Periodic inspection, testing, and maintenance based on BS EN 62446-1.
- Training end-users on safely operating and maintaining PV systems.
However, installers often market PV systems as “maintenance-free,” and such training is rarely evidenced.
PV systems on commercial sites and fire risk
Designers of PV systems are not required to consider the fire protection of property assets, focusing instead on whether the roof can bear the system’s weight. Therefore, specific fire safety regulations regarding PV system design and installation on combustible roofs are limited, and fire brigade input may be necessary.
DC current risks
Even when isolated, PV systems continue to generate Direct Current (DC) in the presence of light, making the wiring live. This poses a risk of electric arcing and overheating if not adequately managed.
Rooftop vs. ground-mounted solar panels
In the UK, ground-mounted systems make up a small percentage of total solar installations. Both types of systems share similar fire risks since they are electrical power generation systems, though ground-mounted systems are more prone to theft and unauthorized access.
Fire risks from atteries
Residential solar systems are more likely to have batteries compared to commercial systems, which usually feed directly into the grid. There is no definitive data on whether batteries are the most common cause of PV system fires, though electric arcing is often a significant risk.
Impact of cheaper solar panels
The recent influx of cheaper Chinese panels into Europe has driven prices down, but beware of quality. All panels used in the UK must meet certification standards like UL, FM, and TUV-SUD to ensure safety and reliability.
System lifespan and fire risk over time
PV systems have varying lifespans for different components:
- Inverters typically last around a decade
- PV panels generally last several decades
- As components age, the risk of failure and fire increases, especially in electrical systems.
Theft risks
Theft of solar panels, particularly ground-mounted systems, is a growing concern due to their value and the presence of precious metals. Roof-mounted systems are less at risk due to their inaccessibility.
Building compartmentation and solar panels
The installation of PV systems can potentially breach building compartmentation, impacting fire safety. Robust planned preventative maintenance, periodic inspection, and testing are essential to maintain fire safety standards.
Insurer requests for annual inspections
Some insurers have started requiring annual inspections for solar panel systems. This trend reflects a growing emphasis on managing the risks associated with solar panels and is likely to become more common.
Aesthetic modifications and fire risk
Edging or other modifications around PV systems can negatively impact ventilation and airflow, increasing the risk of overheating. It’s important that PV systems are installed and maintained as designed to ensure safe operation.
Additional controls for solar systems
“Nice-to-have” controls for larger systems include:
- Automatic fire detection linked to a Building Management System (BMS)
- Integration with the fire alarm panel for early fire detection
Automatic shutdown during fire
Linking PV systems to fire alarms for automatic shutdown of the AC side is a valuable safety feature. This helps first responders by cutting off power during a fire, though there may be concerns over false alarms.
Encouraging the use of solar power safely
Despite the potential risks, solar panels are an effective way to improve energy efficiency. The industry needs clearer regulations and guidance to ensure that solar systems are safe to use, and insurance rates will likely stabilize as risks are better controlled.
