Wildfire is a constant danger in many rural and remote areas, where off-grid PV systems are most common. Rural fire departments respond to both wildland and structure fires, ever mindful that each type of fire can quickly turn into the other. Federal, state, county, and other local wildland fire agencies often respond to all fires in their area as “mutual aid,” depending on whose land is or might become involved. Unlike their counterparts in the suburbs and cities, wildland firefighters do not carry equipment to ventilate roofs or enter burning buildings, and usually do not have enough water or apparatus available to extinguish a burning building—their job is to prevent your home from igniting in the first place.
Prevention & Preparation
The more remote your area, the more responsibility you must take for fire prevention and preparation at your home. The time to prepare, though, is well before fire season—not when the sheriff drops by and tells you to leave within 15 minutes.
Keep your system clean and clear of flammable debris. Regularly remove any leaves, pine needles, or twigs caught between your PV modules and the roof. Firebrands can be carried by wind for long distances and can easily ignite such litter. If your PV array is on a ground-mounted rack, keep grass and brush trimmed underneath and around it.
Label all racks, combiner boxes, and conduit. Should burning debris land on your roof, firefighters may need to climb up there to extinguish it, and may not understand the electrical hazards from PV modules. Simple warning labels—such as “Caution: High-Voltage Solar-Electric System”—could help prevent personal injury as well as avoid damage to your system and home.
In an Emergency
Your ever-reliable off-grid system can help keep firefighters safer while they are protecting your off-grid home and give them a critical edge in saving your home from an approaching wildfire. The key: Leave your PV system on when you evacuate!
In remote areas with no fire hydrants, shuttling water in fire engines is a difficult problem. Prepare a sign in advance with details about your water—where it is, how much there is, and how to access it. Post the sign on your front door before you evacuate, and leave the porch light on to illuminate the sign and make your home visible to firefighters at night. Make sure all of your doors are unlocked—to your home, outbuildings, and water pumping control point.
Since your PV system has been left on, your domestic water pressure pump will be working. Connect garden hoses to outdoor faucets before you leave. If your well pump requires a generator to fill the cistern, then keep the generator gassed up, with instructions posted on how to pump from your well.
Also, keep in mind that “scene lighting” for a typical wildland fire crew consists of helmet headlamps and fire engine headlights. Your outdoor lighting could be very helpful for defending your home.