Can solar panels cause my roof to catch fire?

As with anything electrical, poorly designed systems, badly installed electrical equipment, faulty products, and misuse will all carry a fire risk. However, by understanding your solar panel system and removing all potential fire hazards, you can easily eliminate the problem. We explain why our Enphase microinverter solar panel systems prevent and minimise the risk of solar fires and other dangers.

High-quality products

All solar panel systems include a nifty piece of equipment called inverters. There are two types of inverters: microinverters and string inverters. They both do the same job of converting the direct current (DC) which solar panels generate into an alternating current (AC), which is the type of electricity used in your home. However, they go about the process in different ways.

Enphase microinverters have many years of innovation under their belts and are built to last the full life of a solar energy system. They are completely encapsulated in silicone to ensure their robustness and long-term safety. It also means they will suffer no degradation during their generous lifespan.

Low voltage

Microinverters are installed underneath each solar panel on your roof and are directly connected to the output of each panel. This means microinverters can immediately convert the DC that is generated in that solar panel into a low voltage AC. Enphase microinverter technology will guarantee it stays below 60 volts DC which is obviously a safer approach for both installer and homeowner.

Old style string inverters work differently. A string inverter is a standalone box that is typically installed close to your main service panel and electricity meter (typically on the lower floor of your home). Direct current runs through cables from each solar panel on the roof, down to the inverter inside your home before it is converted to lower voltage alternating current. As a result, the DC voltage in a circuit can increase significantly on the roof of a home or commercial system and this can bring risk.

Tarven Solar Energy Director, Jake Syrocki adds:

“By using Enphase microinverters you will not be bringing high voltage DC into your home or building. The low voltage AC ensures that there is no build-up of high voltage DC in your system and, therefore, in the case of a short circuit or damage to cables whereby current continues to flow, no electric arc can occur. Plus, in a microinverter system there is only one cable in a series connection and therefore much less need for cutting, extending, insulating, or grouping. In comparison, a string system can involve multiple cables which impacts the risk of damage or fire taking place”.

Rapid shutdown capability

Enphase microinverters boast a rapid shutdown (RSD) function. This means that in the event of a power cut, or if you hit the off switch, microinverters stop producing power. There is no power left in the system within a mere 30 seconds. This is beneficial because:

Anyone or anything that encounters the panels during an electrical power failure will avoid serious shock. Plus, the voltage in the cable circuit will already be significantly lower prior to the power going out, due to the fact microinverters immediately convert DC to AC.
The risk of fire is eliminated.
Enphase’s newest microinverters offer split-phase power conversion capability which basically mean that essential appliances like lights, fans, and phones are still able to run during a daytime power cut – even without a home battery.

In comparison, string converter systems will continue to pump DC through its cables until the sun stops shining, even when the inverters are switched off. This is because there is no built-in RSD function. This obviously carries a greater risk of electrical hazards.

Monitor the energy output of each solar panel

Enphase microinverters are connected to every solar panel in the system which allows homeowners to monitor the energy consumption of each solar panel. Aside from homeowners monitoring their energy output, it can also help pinpoint fault detections and other performance issues. With microinverters such as Enphase, if one panel has a fault, you still have the other panels in working order. Meanwhile, in a string inverter system, all the solar panels in the circuit will stop working if the inverter fails.

Early fault detection can identify issues like faulty wiring or electrical connections which can lead to electrical fires or pose electrocution hazards to workers, residents, or the surrounding community.

How to prevent or reduce solar panel fire risk

Preventing or reducing the risk of solar panel fires is crucial for the safety of your solar installation and the surrounding environment. Here are some steps and precautions you can take to minimise the risk of solar panel fires:

Regular inspection and maintenance: Schedule regular inspections of your solar panel system by trained professionals. This includes visual inspections and electrical testing.
Ensure that all electrical connections are secure and free from corrosion.
Check for signs of wear and tear, including damaged or discoloured wiring, loose connections, or damaged panels.
Clean your solar panels regularly to prevent debris buildup that can increase the risk of overheating.
Use quality components: Invest in high-quality solar panels, inverters, and other components that meet industry standards and have a reputation for safety and reliability. We highly recommend the Enphase brand when opting for a microinverter system.
Ensure that all components are properly certified and compliant with local electrical codes.
Proper installation: Have your solar panels installed by qualified and certified professionals who are knowledgeable about local electrical codes and safety regulations. You will also have peace of mind that all electrical connections are properly made, and conduits and wiring are installed correctly. Our team of installers are all NICEIC approved contractors and MCS certified. The team have a wealth of knowledge and experience between them and have installed thousands of solar panel systems in homes across the South East of England.
Monitor the temperature: Enphase microinverters are resilient up to 65°C ambient temperature and 85°C internal operating temperature – any higher and they will shut down. As microinverters are fitted per panel, any fault is contained to a single panel instead of up to 10 panels in a series.
Fire barriers: Maintain adequate spacing between panels and other structures to allow for an airflow around them. They have built in temperature monitoring capability, as outlined in the point above.
Fault detection: Enphase has an overcurrent protection device (OCPD), protected by an RCD with a miniature circuit breaker (MCB)/RCBO which will detect faults in the cable all the way to the microinverter, DC systems do not have this and rely on the connections within the system being adequate.

In some situations, our solar team may install a smoke detector system where an appropriate existing system is not in place, but it is not a requirement. We would install a cement board on the wall if it was made of combustible material i.e. a stud partition (this is normally for batteries).

By taking these preventive measures and staying vigilant, help ensure the safety and reliability of your solar installation.

In all the years our team have worked with solar panels and among the hundreds of projects the team have completed to date, we have never heard of a fire caused by our solar panels. The 25-year warranty held by our Enphase microinverters reflect the quality and safety of our products and installations. If you have any further questions, or would like to call for a quote, contact us today 020 3918 2902.

Take the leap: Call us

Choose us for high-quality solar panel installation or electrical services. Getting started is as simple as contacting us on 020 8087 0216 or sending an email to enquiries@tarvenlimited.co.uk.