I'm an electrician by trade so metering my usage is easy. My math on running a 1300 watt heater 24 hours a day isn't wrong but I could be wrong as to whether that's enough heat to keep the RV warm. Personally I like my space relatively cool year round. One thing I am doing a little bit of research into right now is building a tiny house or a shipping container house instead because I don't need the portability of a fifth wheel but we'll see where that research leads me. It seems like the biggest concern most people have is Heating and insulation in a fifth wheel which honestly has put that at the top of my radar