The difficulty with mortgage lenders and solar panels is with the people who have effectively sold their roof to a company. the home owner gets the panels fitted for free and benefits from the lower priced/free electricity but they do not get the feed back tariff; that goes to the power company who own the solar panels. So, if you go to sell your house, technically you do not own all of it, your roof has been leased by another party. New build with solar panels are a totally different legal situation. Also, on new builds, the panels are often the less obvious ones, whereas there are many houses around here with the really ugly whole roof set up and although the owner may not be bothered by what they look like, it is not a pretty sight for those living opposite.