I think you would find that those in the 'sunny' western states use solar a lot more than eastern. Full-timers use solar a lot. It's a big investment but full-timers are in their homes constantly. We full-timed with solar very successfully and could stay out in the boonies forever if it weren't for getting water and dumping the tanks. However, after two weeks we always got anxious to move to another spot so that generally was our limit.
We didn't stay in places of extreme heat in the summer so didn't need an air conditioner.
RVs are sold with the tiny solar panel to charge a battery but it's definitely not enough to live on.
Full-timers getting a new RV will remove the panels before selling in order to put them on the new one.
Solar is the way to go in the West!