https://www.youtube.com/watch?...
We have one of these in our fifth wheel camper. It's occurred to me this would be wonderful in the GH. Temperature controlled -you tell it how hot it can get inside before it opens. Closes if it rains or gets too windy,
Not cheap -- but maybe a camper dealer would have some used. It's 12 volt. My husband is thinking about a solar charged 12 volt battery.
