Wood
Wood has been a heating source for countless centuries. It is still man’s primary means of heating. Fireplaces provide both warm and a welcoming atmosphere that attracts many. Wood can be burned in the fireplace, in wood burning stoves, or more elaborate wood heating systems. The biggest advantage to wood as a heating solution is that it a renewable source. Trees can be used and then replanted.
Of course, wood does have some disadvantages. If you live in certain areas, the costs for having sufficient wood to heat your home during the winter can add up. If you have land with trees on it, you may be the one cutting the firewood and hauling it back home. It might also be pointed out that wood is not the most efficient heating source; also, it does not burn as clean as natural gas