Solar panels generally have a positive ROI. Except it is lower or even negative right now over parking lots because of legislative barriers and because the pro

Solar panels generally have a positive ROI. Except it is lower or even negative right now over parking lots because of legislative barriers and because the process hasn't been streamlined. If it is legally mandated rather than legally difficult, and everyone is doing it, these costs reduce. By forcing everyone to do it you break the first-mover disadvantage. The lot owner (or whoever they want to license the space to) benefits. Cities get 25% lower heat-island effect. Customers get cooler cars. Less productive land is used. Everyone wins, and the law has an 'economically untenable' clause for people in the shade of a highrise or with trees or existing shade sails or similar.