I have a back up plan, first I have those gel type packs, can use them for freezer or heat, put them in hot water, since you got a wood stove, you can heat them in a pan of hot water, I put my bp's in home made snake bags for this purpose and then put them in a smaller tank like a 10 gallon for now, and put a screen lid over it and cover part of it to keep heat in... the snake bags just keep them confined a bit and make it easier for me to regulate that they are not getting burned. They can be reheated the same way with no probs..I get them from work for free cause they come in with our fish shipments, so I have lots of them, so I can have a set to rewarm while they are using a set Also, we are getting a generator to have wired into our house in the basement for this reason so the house is not without electric. But until we do that, its hot packs and snake bags!