I think you're kind of missing the point, having solar panels in parking lots would add use to otherwise useless land. There's plenty of them in the US and it would also create a relief from the concrete hotspots that it makes. I mean have you ever been walking through a parking lot and hating your life because you're sweating so much?
I get that. That really makes sense. Tho it kind of makes it harder to then justify getting rid of parking to improve density. But this will most likely also not happen otherwise so yeah
There are solar generating facilities literally everywhere now. To mount them high enough to park under is a miniscule cost difference. There are also already massive parking lots with covers all over the place. We have probably 5,000+ covered parking spaces at the airport in my city, for example