Spent 2 nights here on our trip to Custer, Yellowstone, and Teton.
This stop was dry camping, we relied on our solar panel a lot, and it never let us down, with lights, television, and ventilation fan running we were nearly depleted just before day break, and by the end of the day of full sun we were back up nearly full. I believe power wise we could have stayed off grid for quite some time.