Seeing fewer rooftop solar installations when I visit my home state (Texas) than I see in the one I live in (Bavaria) is a trip. Yes, I know that electricity is far cheaper there than here, but as much electricity as air conditioning eats, and as big as those roofs are (panels are cheap; it's the system that's expensive), it should balance out.

Anecdotally, a ton of solar has gone up in the last four years here in Germany, both rooftop and, increasingly, in what were likely canola fields for biodiesel along highways - at first driven by Russia's invasion of Ukraine and the need to reduce natural gas consumption, but now by how absolutely cheap those panels are. Too bad they're not being made here...

My favorite installation so far: a large field in SW Germany, with the panels high enough for cattle to wander and grass to grow under them. The cattle were almost all under those panels, munching away - it was a hot day.