Yeah to fully charge for longer drives you kinda need the roof of your house. I know a few people who drive EVs fully charge on solar like that.
I don't have a car so no need myself and ebike restrictions are so extreme in the UK that I don't see the point for myself. 250w and 15.5mph limit, I can cycle pretty much that fast anyway. 13mph is the AVERAGE speed I go to work and that includes stopping for cars and lights. So potentially a road legal ebike would just be a dead weight motor to pedal against most of the time.
A spare wheel with a motor on it that I can swap between to convert it into an ebike for long distance rides could be cool. But ebike throttles are also not road legal. Must be pedal assistance only, and that seems like it might be quite a lot to convert it each time I switch. Maybe I need to talk my partner into getting an ebike that we could both use...