I believe solar panels should be utilized in areas with most sun, for sure. Place like UK? The place where it's always cloudy, raining and depressive? Not so much, it's negligible, solar panels can pay off for sure even in places like that I believe, but don't trust my verdict on that. I do believe that everyone should utilize them when there's the chance and no better place to put your money into, it would not be about ecology for me, but about effectivity and monetary returns, Biggest problem with my house and most the apartment blocks here - Flat rooves. Although I don't know how specifically it affects solar panels, but I think it still does, has to do with angling I believe.