In a 24 hour period the sun produces enough energy to supply our planet for over four years. That’s 1,460 days of solar energy the planet received in just 24 hours. Solar energy is everywhere and the advancements in it are growing and for many reasons. It's renewable, pollution free and cuts costs of other energy sources. What's this mean for firefighters? Well it means a lot. Solar panels are popping up all over buildings and on plots of land like never before. We're noticing this by a simple placard found on the commercial structures that are now using solar energy with the letters "PV" on it.

“PV" which stands for photovoltaic is the method of converting solar energy into direct current electricity (DC) using semiconducting materials that exhibit the "photovoltaic effect". The "P" which stands for photo (light) and the "V" which stands for voltaic (electricity), this of which it bears its name. The PV effect is the creation of voltage or electric current in a material when exposed to light.

In today's society, solar panels are everywhere just like truss construction is everywhere. Thus creating a need for firefighters to be aware of the dangers and understand how to attack fires with PV systems.

For firefighters to be safe and operate efficiently on the fireground, there are a few critical steps we must take to ensure the solar panels are accounted for and in check. Do not begin fire suppression until these first 2 steps have been completed.

360 Size-up: This is a no-brainer. By performing a 360 size-up upon arrival, firefighters are able to possibly locate the panels or the energy storage system (ESS) if the panels are on the roof or an area without access to at the time. Most of the time depending on jurisdictional building codes, the ESS panels are located on the exterior of the structure normally near the utilities, the garage or the basement, should the structure have one.
Treat this as an electrical fire and turn off the systems starting with the utility grid. The main breaker box will activate the backup battery and run the risk of electrical shock to interior firefighters in the structure. If the battery is located in a confined space in the structure and exposed to heat above 150 degrees Fahrenheit, it is imperative that ventilation of that space begins.

Once the size-up has taken place with the panels and/or ESS located along with fire suppression taking place, ventilations needs to begin. However, firefighters and command need to understand that if the panels are located on the roof and are burning, there is a potential for collapse based on the volume of fire around the panels and on the roof.

When performing ventilation, especially vertical ventilation, firefighters must recognize that electricity is being produced by the panels 24 hours a day.

Once these steps have taken place, fire suppression can now continue. As a safety precaution, firefighters should try and extinguish the fire at a minimum of 20 feet away when using a straight stream or a minimum of 5 feet when using a fog pattern.
After the fire has been knocked, overhaul can begin - carefully.

Panel safety

Firefighters should be careful not to touch any of the panels in case of any damage done to them during the fire. Instead, firefighters should cover the panels with canvas tarps, especially at night due to no sunlight exposure to them. The reason panels should be covered during night operations is due to the wires running through the conduit to the charge controller or inverter which continues providing the panels power.

Battery safety

If the battery was the source of the fire, continual water flow to the extinguished battery is important to keep the battery cool and from the possibility of obtaining a chemical reaction causing a thermal runaway. Should a thermal runaway occur, the temperature inside the battery will reach the point that causes a chemical reaction inside the battery. This reaction produces more heat and drives the temperature of the battery higher, causing further chemical reactions and more heat. In thermal runaway, the battery cell temperature will rise in milliseconds and release suddenly. The chain reaction will reach temperatures of around 752 degrees Fahrenheit and produce gassing of the battery along with fire.

Burns tests have shown that lithium-ion batteries can produce these chemical reactions 72 hours after extinguishment.

As technology changes, firefighters need to be educated and trained on all of the new advancements in the market today. By doing so, firefighters can continue to develop a proactive approach to new technology when responding to incidents. Solar panels may not be completely new to us but the growth of them in residential and commercial structures has rapidly increased over the years. Today, it is nearly impossible to not catch a glimpse of solar panels on almost every street across the country. Stay diligent to the advancements in the world and continue to keep training and getting after it.

Until next time; work hard, stay safe & live inspired.