There probably aren't enough roofs and parking lots to run civilization plus produce enough calories to feed us. Deserts are nice but then you're talking about

There probably aren't enough roofs and parking lots to run civilization plus produce enough calories to feed us. Deserts are nice but then you're talking about a lot of long-distance transmission, which gets expensive; most likely if we end up with a lot of fallow farmland closer to consumers, we'll use that. Still a great trade going from 40% to 4%. But if we do manage some kind of really cheap nuclear, that'd be even better.