The Fire Hazard Through The Solar Panel System?
At this point, it can be said that a standard-compliant solar panel system does not increase the Fire hazard in a building. However, in some cases, the fire is not caused by the solar PV system.
In this case, it is not just a case of whether the solar PV system will be destroyed or not. The decisive question here is whether the firefighters can extinguish the fire in the house, on whose roof or façade a solar panel system has been installed.
1. In the event of fire: Dangerous electricity with an existing solar panel system
This danger is caused by current-carrying components of the solar PV system.
In most cases, a solar panel system cannot be switched off completely. Even if the AC-side is turned off with the help of an appropriate switch in the solar power inverter, this is not the case for the DC-side.
The voltage remains between the solar array and the disconnector. However, In the event of a direct current, a voltage of 120 Volts is fatal to humans.
An additional danger for the firefighters is when the connectors or plant components are incorrectly disconnected. This can cause electric arcs, which pose a significant threat to the life and limb of the firefighters.
After the firefighters extinguish a house fire, water can accumulate in certain rooms. If the firefighters enter the home, and current-carrying components of the solar PV system are present, then there is a significant danger of electrical shock.
Naturally, by the risks mentioned above not only the firefighters are in danger, but also other people, inhabitants, rescue teams, for example.
2. Other Fire Hazards
Among the dangers from electricity, there are further points, which make extinguishing the fire at least more complicated and costly.
Solar PV panels and cables contain materials, from which toxic substances can be released in the event of a fire.
This can come not only from the cable sheaths but also from other plastic materials that are used in the production of solar PV modules. These can endanger the people as well as the local environment.
A particularly great source of danger represents the so-called chimney effect in the solar panel systems. They are usually mounted with a distance of about 10 cm to the roof. In the case of fire, the resulting draft can fan the fire, making the fire spread rapidly.
Just as dangerous is a fire which has perhaps just started and is overlooked because the roof is covered largely by the solar panel system!
3. Important protective measures
Here are the most important protective measures, which are recommended by the fire department:
A) PV fireman’s switch
The best protective measure, which is recommended by the fire department, is the so-called PV fireman’s switch. It offers the possibility to disconnect the solar PV system.
B) Indicating sticker for the solar PV system
It is helpful to place an indicating sticker at the house, which calls attention to the existing solar PV system.
C) General plan for the solar panel system
Because the fire brigade is unaware that a solar panel system has been mounted on the roof of a house, they recommend the plant operators to establish a general plan for the solar panel system, which should be readily available from outside.
The general plan should contain all information, which enables the fire brigade an orientation and an adequate response.
D) Respiratory protection
The fire department also recommends, in the case of unknown fire protection class to wear breathing masks.
This allows protection from toxic substances, which can be released in the case of fire. Also, switching off the ventilation systems is a preventive measure. This ensures that the fire does not spread easily.