Using solely electricity to power your heater is often difficult if not impossible in the winter without a direct mains electricity supply or campsite electricity. The demand in the winter is too much and the generation is too little. Things like solar panels may have been a solution in the summer but cannot generate enough electricity in the winter. Solar panels work in the cold, in fact, they are even slightly more efficient in the cold. Light reflected from the snow can help the solar panels reach high levels of efficiency. However, the fact that the days are shorter in winter means that solar panels will still generate less electricity in the winter than in the summer. For these reasons heating solutions that require minimal electricity are the best solutions for the winter. Propane is best stored in well-ventilated, cool places. In this way, it is okay to store propane in a locker where it might become very cold because of winter temperatures. The condensation point of Propane is -42 degrees Celsius. It is improbable that you will be venturing anywhere that will reach that threshold and probably not in an RV. Propane is a popular method of heating for RV users and there are lots of choices so that you can select a heater that offers the functionality, safety, and heating potential that you need.