Heating is a huge expense for many households. It also accounts for about 56% of the energy used in a home. Thats why many people are looking to mother nature for help. Dave Fulmer has built a home thats powered by the sun, the wind, and the earth.The earth surrounding Daves home will trap heat in the winter.In summer it will keep the house cool. Solar panels bring in more energy. Dave certainly represents one end of the spectrum. Of course there are meaningful things you can do without building a brand new green home. You could start by performing an energy audit. Drafts and leaks can waste vast amounts of energy, and theyre not just around windows and doors.They can be found around electrical outlets and switch plates, fireplaces, and attic doors. Just by eliminating drafts many people can reduce their energy use by up to 30 percent. Its also important to make sure your insulation levels are up to todays standards.Regularly inspecting your furnace is also a good idea. Of course there are big-time projects that can have even more impact. The bottom line on heating is this: You can think as big or little as you like, but any action is better than none at all. Converting one million homes to geo-exchange instead of oil or natural gas heating systems would reduce carbon dioxide emissions by 9 billion pounds.