Portland, OR

 
System TypeEfficiencyTotal AnnualSample Annual Costs
kWhccf/gal6¢/ kWh; 60¢/ ccf; $1.00/gal
Geothermal3.5 ton 1 speed
4.0 ton 2 speed
10,790
9,918
0
0
$647
$595
Air-Air12 SEER
14 SEER
18,362
17,543
0
0
$1,102
$1,053
Gas80%/10 SEER
90%/12 SEER
2,834
2,649
1,461
1,348
$1,047
$968
Propane80%/10 SEER
90%/12 SEER
2,834
2,649
1,589
1,354
$1,759
$1,513
Oil
(W/elec DHW)
80%/10 SEER
80%/12 SEER
8,366
8,181
818
818
$1,320
$1,309

The table above shows the typical annual energy cost in Portland. 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 were used to calculate the cooling and heating loads, with some adjustments in the home construction representative of the weather area.

In this example, the summer heat gain and winter heat loss is matched with the HVAC equipment and the annual total kWh of electricity, 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.

Note:
If your energy costs are different from this example (6¢/kWh, 60¢/therm or ccf of gas, or $1.00/gal oil or propane), here's how you can adjust the annual cost estimate:

  1. Estimate what you pay in your area in $ per kilowatt hour power cost and applicable fuel cost – gas in $ per hundred cubic feet (ccf) or per therm; propane or oil in $ per gallon.
  2. Multiply your energy unit costs by the Total Annual values shown in the table. Adding the two (electric and fossil) together will show you the typical annual operating costs for your area.

Example:
Gas 80%/10 SEER system in Detroit with $0.06/kWh and $0.60 per therm gas. (from Detroit table)

Gas %/10 SEER
Electric4,941 kWh/year times $0.06/kWh= $297
Gas1,627 Therms/year times $0.60/therm= $976
 
Base Case (Geothermal 1-Speed)
Geothermal13,346 kWh/year times $0.06/kWh= $801
 Annual Savings= $472