Half-life of a brilliant idea

This is sometimes how my brain works:

Me: I wonder if there would be a way to turn the parking lots into some kind of solar energy

Me, five seconds later: Unless those parking lots are for a breakfast / lunch place then most of their time in the sun will have cars parking on them.

I'm sure there's a kernel of a good idea in there somewhere, but unless we can come up with transparent or invisible cars it's probably a non-starter.