About half of U.S. homes use methane gas for heat. With the increasing costs, many have seen their bills skyrocket. Wood banks have quickly become an alternative for those stretched for money. While wood is not the cleanest heating source, it is often the only affordable option available. Wood banks can be beneficial by using wood that would have otherwise ended up as waste. b"A lot of the climate change challenges actually are opportunities for wood banks," said Professor Leahy at the University of Maine.