Residential Operating Cost Comparisons

For comparison, use a 2,000 square foot home using a nominal 3½ ton Geothermal Heat Pump system with a single speed compressor as the "Base Case."

The annual operating cost includes:

  • Heating,
  • Heating Auxiliaries (specifically,
    • electric resistance heat for geothermal and air-to-air heat pumps, and
    • blower fan kWh for fossil fueled heating),
  • Cooling, and
  • Domestic hot water (specifically,
    • electric on geothermal and air-to-air heat pumps and oil systems, and
    • gas or propane on the others).

To view a comparison of the annual energy costs of the geothermal heat pump system with nine alternative systems, select the city whose weather most closely resembles where you are located.

Portland, ORDetroit, MIBoston, MA
Salt Lake City, UTMinneapolis, MNRichmond, VA
San Francisco, CASt. Louis, MOCharlotte, NC
Los Angeles, CATrenton, NJAtlanta, GA
Omaha, NEIndianapolis, INTampa, FL
Oklahoma City, OKHouston, TXMiami, FL

The comparison is based on a power cost of six (6) cents per kilowatt hour, and natural gas cost of sixty (60) cents per hundred cubic feet (ccf) or per therm, and propane or oil at one dollar ($1) per gallon.

Each city display shows the typical annual energy cost in that general area. These costs are based on a well-insulated 2,000 sq ft 1-story home. The home has 3-bed rooms, 2-baths, with living room, dining room, family room, laundry room, and kitchen. Its indoor design dry bulb temperature is 70°F in winter and 75°F in summer. Typical weather conditions in the area represented by that city were used to calculate the cooling and heating loads, with some adjustments in the home construction representative of the weather area.

The summer heat gain and winter heat loss is matched with the HVAC equipment and the annual total kWh of electricity, therms* or CCF of natural gas, and gallons of oil or propane calculated for each of the 10 systems. Domestic hot water is included based on the use of a desuperheater, plus an electric water heater for the geothermal heat pump systems. Electric water heaters are used with the air-to-air electric heat pump and oil systems. Gas or propane water heaters at 70% efficiency can also be used with these systems.

*1 therm = 100,000 Btu = 1 CCF