Heat Pump vs Gas Furnace Calculator
| Electric \ gas, $ per therm | $1.00 | $1.50 | $2.00 |
|---|---|---|---|
| $0.12 per kWh | Gas furnace | Heat pump | Heat pump |
| $0.17 per kWh | Gas furnace | Gas furnace | Heat pump |
| $0.25 per kWh | Gas furnace | Gas furnace | Gas furnace |
Enter your electric and gas rates, how cold your winter runs and the furnace you own. The calculator converts both systems into dollars per million BTU of delivered heat.
The comparison is a rate race: a heat pump moves heat at three to four times the electricity it draws, while a gas furnace turns about 80 to 95 percent of its fuel into heat. Which wins is set almost entirely by your local rates - about 60 percent of US homes have gas at prices that keep the furnace competitive, and the calculator draws your exact line.
How to use
- Both rates come off your utility bill - electric in cents per kWh, gas in dollars per therm.
- Set the COP honestly: 3 in mild winters, 2.5 temperate, 2 in cold snaps, 1.5 in deep cold - efficiency falls as it freezes.
- The furnace AFUE is on the yellow sticker; 80 is aging, 95 is modern. The verdict updates live.
Frequently asked questions
Is a heat pump cheaper to run than a gas furnace?
Where electricity is cheap or gas is expensive, yes - the swap line sits near gas costing ten times your electric rate per therm. At 17-cent power and 1.50 gas the furnace wins on running cost; the calculator draws your exact line at your rates.
What does COP mean on a heat pump?
Coefficient of performance - the heat delivered per unit of electricity. COP 3 means three units of heat per unit of electricity, which is why a heat pump can beat burning gas even though power costs more per unit than gas. The COP falls as outdoor temperature drops, which is the whole nuance.
Do heat pumps work in cold climates?
Modern cold-climate units hold useful output well below freezing, but the efficiency still slides: a COP of 3 in November can be 1.5 at minus 10. That is why the calculator lets you set the season efficiency - price the deep-cold nights, not the average day.
Does a heat pump replace air conditioning too?
Yes, and that is half the financial case: the same equipment cools in summer, so the comparison is furnace-plus-AC against one heat pump. The running-cost math here covers winter; the avoided AC replacement stacks on top.
When is the right time to switch?
When the furnace dies anyway. Equipment swap costs thousands either way, so the honest trigger is end of life: running-cost differences alone rarely repay a working furnace, but a dead one makes the heat pump the default quote to beat.