Heating and cooling your home uses more energy and costs more money than any other system in your home -- typically making up about 54% of your utility bill.
No matter what kind of heating and cooling system you have in your house, you can save money and increase your comfort by properly maintaining and upgrading your equipment. But remember, an energy-efficient furnace alone will not have as great an impact on your energy bills as using the whole-house approach. By combining proper equipment maintenance and upgrades with recommended insulation, air sealing, and thermostat settings, you can cut your energy use for heating and cooling -- and reduce environmental emissions -- from 20%-50%.
Energy Star - U.S. Environmental Protection Agency - U.S. Department of Energy