Up North and Off Grid

In a cold climate, effective and efficient heating systems are paramount. Because I'm off-grid, I also want a heating system that is fail safe, that is, at least one of the heating options has to be chosen so that it works even if there is no power at all. I wanted at least a couple of systems that work well together, and provide a level of redundancy. We have a couple of options to work with; I will discuss both the advantages and disadvantages.  Before I get to that though, we need to have some idea of how much heating we're going to need. This will determine the size of the heating system, how long they can work between firing/charging sessions. This is going to involve some math - math is good! Heating losses What determines the size (in terms of power and stored energy) of the heating system is essentially one thing: heating losses. If there would be no losses at all, you'd heat up the place once and you're done. This is of course not realistic. Heating losses are