Are rooftop Solar Panels safe for you and first responders?

| Solar Blog

There are some things we don’t think about until it actually happens, and the last thing you want is to install solar panels and be unaware of the risks if there’s a fire in your home or business. Firefighters and first responders cut off the power to a building that’s ablaze as a safety precaution, what many people don’t know is if the building is supplied by solar power the system will continue to generate energy, even if it isn’t connected to the AC grid.

An increasing amount of fire and electrical authorities, and insurance companies around the world are enforcing new regulations and standards to increase the solar panel safety and ensure that all persons and property is well protected, and at Solar Warehouse Australia your solar safety is our priority.

The risk of electrocution can be high if the connected modules generate more than 150V, as a safe voltage for electrical systems is only 120V. The voltage is even more so if the modules are connected in a string which can reach anywhere between 600V to 1500V – this is extremely dangerous for first responders during an emergency.

So how do the PV modules turn off during a fire? Unfortunately trying to shut down the functions of inverters only interrupts the current flow which voltage remaining live, and automatic DC breakers on the inverter in the cabinet cannot disconnect the voltage on the modules either.

Trying to spray foam is also ineffective as the foam evaporates off the modules before extinguishing the flames, and covering the module with opaque material in the day time can be more dangerous for the first responders, requiring them to climb atop the burning building with heavy materials, risking injury and electrocution. Rooftop array isolators don’t help either, as rooftop DC isolator switches only disrupt the flow of current from roof to inverter – modules, their cabling and cabling to the inverter remain dangerously high during the daylight.

The most effective way to lower risk of electrocution for first responders and personnel is module-level shutdown. This can be achieved by first installing a solar panel with a power harvesting system which has power optimizers in each module, inverter and module-level monitoring. With power optimizers connected, they continue to run as long until it is deemed no longer safe to operate – a signal is sent from the inverter, once there is no signal, the module automatically shuts down the DC current along with voltage in module and string wires.

This ensures the safety of those tending to the fire as the output voltage of each module equals to 1V, so even if there is the maximum string length of 50 panels connected to each other, the highest voltage is limited to only 50VDC.
Ask us how you can learn more about this uniquely safe solar solution and get a obligation-free quote from Solar Warehouse Australia today!