And it's a good idea to try to whittle down your bill: According to the Department of Energy, heating and cooling costs account for 56 percent of the energy use in an average American home. Add blankets to the bed. For every 1 degree you set your thermostat back, you can save 1 to 3 percent on your annual heating costs, according to Joe Ruggiero, heating products manager at F.W. Webb, a wholesale heating and plumbing distributor headquartered in Bedford, Mass.