There was an interesting article on Treehugger.com about an interview with Ray Burgess, president and CEO of Solar Power Technologies. In the interview Burgess is quoted as saying, "Solar panels do not work that well and few know it."
Don't scrap your plans to invest in panels just yet. As a follow-up article in Grist pointed out, Burgess may have been exaggerating just a bit with his statement, which was backed by the evidence of the doubling of energy output from Google's panels after they cleaned them. But Grist was quick to shine the light on this case study, clarifying that the panels in question were flat, while Google's other tilted, rooftop panels are cleaned routinely by rain and don't suffer any shortcomings in output.
It is important for homeowners to know that solar panels do require routine maintenance to perform at optimum levels. This necessity should have potential solar panel buyers thinking about where to mount them. Spending a lot of time on the roof is not for everyone.