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Programmable Thermostats Conserve Energy and Save Money

A programmable thermostat is one of the most reliable energy savers available. A programmable thermostat adjusts your home's temperature automatically to save energy when your family is sleeping or away from home. If used properly, a programmable thermostat can save 10 to 15 percent on heating and cooling costs.

Any thermostat is simply an automatic on-off switch for your heating or cooling system. During the heating season, when your home's temperature dips a degree or two, the thermostat turns the furnace on. After the temperature rises to the desired level, the thermostat turns the furnace off. The lower the temperature setting on the thermostat, the less energy your furnace consumes to heat the house. In hot weather, the thermostat turns your cooling system on when the temperature in your home rises beyond your chosen comfort level. The higher your summertime set-point, the less energy your cooling system consumes.

Programmable thermostats have a built-in clock that changes the temperature setting of your heating or cooling system to correspond to sleep/waking and occupancy/vacancy. You program the programmable thermostat by choosing the schedule that your family follows. In winter for example, a programmable thermostat can turn itself down 5 or 10 degrees before bedtime and back up to a comfortable temperature in the morning. If your home is empty during summer days, the programmable thermostat turns its temperature up after you leave for work and back down again before you return. The programmed thermostat setting simply reduces the operating time of your heating or cooling system, saving you money.

Programmable thermostats cost $100 to $200 installed. They can save far more than that in energy costs over a few short years.

If used correctly, programmable thermostats can save at least 10% and sometimes considerably more.

See Homeowners Guide to Building Performance or Residential Energy: Cost Savings and Comfort for Existing Buildings Chapter 6 for more information.