So I’ve never really thought of squirrels as being a major nuisance (some out there do, see N.A.D.S.: North American Defense against Squirrels) but this summer, my neighborhood squirrels seemed to have it out for my home solar system.   After returning from a week’s vacation I noticed that my solar output had dropped dramatically.  You can see a significant difference in output between July of this year and July of 2012 that was caused by more than just the rainy weather .  Suspecting that I had some sort of wiring issue, I contacted my friends at Green Earth Solar to come out and investigate what was causing the problem.

 Their diagnosis was that squirrels had extensively damaged the wiring underneath my system.  Squirrels are born with front teeth that never stop growing, so their constant gnawing keeps these teeth from growing uncomfortably long.  Unfortunately, over the past few years squirrels decided to nest under the panels on my roof and use my solar wiring as dental floss.   This became an expensive and dangerous problem, not only for the squirrels who could get zapped, but because the combination of leaves that had gathered under the panels and the damaged wires posed a potential threat of arcing electricity.  We had to shut the system down for about a couple of weeks while they scheduled the necessary maintenance to repair the chewed wire.  Because our house is surrounded by beautiful large trees that provide easy roof access for squirrels, we needed to tailor a creative fencing fix that would keep the furry fellows from gaining access to the area underneath the panels. Luckily, Green Earth Solar was able to devise a solution involving installing a wire screen (see the picture below) that keeps the squirrels out.

Not long after we completed that work I came across a significant article in the New York Times on a similar subject – it turns out that this is a much more prevalent electrical issue than I suspected.  With squirrels causing extensive blackouts and electrical damage throughout the country on a regular basis, squirrels can do major damage beyond taking out one house’s solar output.  See this list for serious examples of P.O.C.B.S (Power Outages Caused by Squirrels, as dubbed by the New York Times) across the country and the Southeast, most notably an incident in which a squirrel chewed through lines powering a wastewater treatment facility in Tampa and forced the implementation of a city-wide boil water notice for the next 37 hours.

Just in time for fall, it seems we may be entering P.O.C.B.S  busy season.  Regional power provider Progress Energy, before their merger with Duke, had this to say in a past press release devoted solely to the squirrel scourge:

“Many outages during fall months are caused by squirrel activity around power lines and transformers. This time of year, before winter’s chill sets in, squirrels and other animals are actively storing nuts for the winter. This increased activity can cause both instantaneous outages as well as extended power outages.”

According to the research done by Jon Mooallem, who wrote the New York Times piece, the power system provides numerous attractions that squirrels find hard to resist: lines to grind their growing teeth, transformers that offer potential den sites, warm places atop poles to bask in the sun, and even food in the form of “seeds and insects” that are sucked into cooling fans at electrical substations.  And they love leafy neighborhoods, like mine, that humans are attracted to as well.

It really is a bit disconcerting to think that with all the electrical conveniences and necessities that modern civilization revolves around, that squirrels have become so effective at creating large blackouts in so many different areas, all with an ill-timed chomp or scamper (or deliberate sabotage, if you side with N.A.D.S). So much for Smart Grid? In my experience as a homeowner with solar panels, I’d advise anyone to squirrel proof their systems from the get-go, especially in areas where large trees provide easy access to your panels.  Other solar users seem to have experienced the same phenomenon, and I wouldn’t be surprised if the problem becomes more prevalent as rooftop solar grows.  Go ahead and add the squirrel guards – you’ll be better off in the long run.