Me too. No power, I have an Atwood furnace in both my Pup and my FWC pop up camper. On those infrequent occasions I’ve camped in flat out below freezing weather, I also use a Buddy heater. Reason is running the Buddy requires no battery. It’s actually a fairly common approach among the boondock crowd. Dbhost’s post on Coleman heaters is good too. My uncle had a 513? Maybe 515? when we were kids. It heated well.