Vodacom Century City fire highlights fire safety for PV systems

The fire at the Vodacom building at Century City in Cape Town last month is suspected of having been caused by an issue with the rooftop solar photovoltaic (PV) installation, notes ASP Fire CEO Michael van Niekerk, observing that such systems for homes and businesses are increasingly popular as a means of mitigating the impact of ongoing loadshedding.

However, he stresses that, for insurance purposes, these systems need to be installed by an accredited installer or electrician. The onus is on home and business owners to ensure that the installation is correct, especially in terms of accompanying generator sets.

“There are several fire safety measures that should be taken into account to prevent the risk of fires when installing a solar power system,” says Van Niekerk. Firstly, solar panels must be installed by experienced professionals to prevent fires caused by faulty wiring or overheating.

It is important to use high-quality solar panels, inverters, wiring, batteries and other components from reputable manufacturers. Inferior quality components, especially when it comes to lithium-ion batteries, are more likely to malfunction, increasing the risk of a fire.

He adds that lithium-ion batteries that are not equipped with a thermal management system have a high chance of overheating, resulting in thermal runaway and a subsequent fire.
Moreover, battery storage rooms must be fire rated to control a battery fire as these are “exceptionally difficult to control and extinguish”. The flammable gas produced during a lithium-ion battery fire can build up inside a garage or room, and if ignited can result in an explosion with disastrous consequences.

Another critical consideration is using properly sized and rated wiring in the installation to prevent overheating, short circuits or other electrical problems that can lead to fires, says Van Niekerk, adding that wiring should be insulated and that conduit should be used where necessary to protect the wiring from the elements.

“Faulty, poor quality or incorrectly installed solar panel junction boxes located outside on the roof can cause water ingress, which can lead to a short circuit and a subsequent fire that [would] result in a loss of the roof-top solar installation.”

He suggests that building managers install an isolation switch to shut the roof-mounted solar panels down safely in case of an emergency.

“Such an isolation switch must be clearly labelled and easily accessible to the fire department. The impact that solar panels have on smoke ventilation and emergency firefighting smoke ventilation in a soft roof building are also important factors to keep in mind when designing solar panel installations.”

Further, Van Niekerk notes that a solar power system must be grounded to prevent electrical shocks and fires.

“All metal components, including the solar panels and storage batteries, must be grounded to a common ground point. Regular maintenance and inspection are critical to ensure all components function properly and to identify any potential fire hazards.”