Get a wood burning stove =]. Ours heats the house to 70 easily, we have gotten it over 80 upstairs from continuous burning. It's about 68 right now closed down on a slow burn. You can find wood cheap, people on craigslist give it away when they have trees cut down too. You will need a log splitter though. We have enough stored for over 2 winters. We do have 750 gallon lp tank, but it's way too expensive to fill, and the house is too old and inefficient, so it's only when we are gone for long periods of time, and don't want the pipes to freeze.
If you don't want to pay for a wood burning stove or a generator, go to tractor supply and get their portable kersone or lp heaters. Make sure you get CO detectors.
If you don't want to pay for a wood burning stove or a generator, go to tractor supply and get their portable kersone or lp heaters. Make sure you get CO detectors.