How Not To Go Solar
On a recent trip to Canada, I passed through Kingston, Ontario — home to Canadian Forces Base Kingston (CFB Kingston). A solar power installation just off the roadway — inside the perimeter of the base — caught my attention. Unfortunately, the reason it captured my attention was because the solar panels looked like the side of a trash can.
The picture tells the story.
Look at the contrast between the above photo (click to enlarge) and the one of clean solar panels below.
So how much can unmonitored and dirty solar panels affect output? A study conducted for the U.S. Department of Energy suggests that unmonitored solar panels can degrade by up to 10% in a year, and according to another study from the National Renewable Energy Laboratories (NREL) “the reduction in power from shading half of one cell is equivalent to removing a cell active area 36 times the shadow’s actual size.”
According to Google, when they cleaned their flat solar panels 15 months after installation they noticed its output double overnight. Eight months later it went up 37% after the panels were cleaned once again. The Google study did note, however, that “rain does a sufficient job of cleaning the tilted solar panels,” so perhaps the fine folks at CFB Kingston are just waiting for a good rain.