Heat Pump Cost Calculator

A heat pump moves heat rather than creating it by resistance, so its electricity use depends on coefficient of performance. This calculator converts a delivered heating load from BTU to kWh, divides by COP, and compares the energy cost with gas and oil at entered efficiencies.

One kWh equals 3,412.142 BTU. Dividing delivered BTU by that constant gives thermal kWh; dividing again by COP gives heat-pump electricity. A COP of 3 means three units of useful heat per unit of electricity.

Gas input equals delivered heat divided by furnace efficiency. Therms are 100,000 BTU. Oil input divides by equipment efficiency and about 138,500 BTU per gallon.

COP changes with outdoor temperature and supply-water or air temperature. Seasonal performance data or a temperature-bin model is better than one COP for a final design.

Worked example

Delivering 34,121 BTU is 10 thermal kWh. At COP 2, the heat pump uses 5 kWh. At 20¢/kWh, that delivered heat costs $1.00.

How to read the result

Compare the same delivered heat and include all fuel charges that vary with use. Fixed gas service fees can change the economics if electrification allows the account to close.

Planning inputs are deliberately editable because two homes in the same state can have different tariffs, roof conditions, equipment, and operating schedules. Save a scenario with “Copy link,” then change one assumption at a time. This makes the result useful for comparing decisions without implying false precision.

Formulas and defaults are documented in our data method. The principal references for this page are:

1. U.S. Department of Energy — Air-Source Heat Pumps (2025) — Heat-pump operation and performance context.
2. NIST — Guide for the Use of the International System of Units (2008) — Energy-unit conversion basis.
3. EIA — Units and calculators explained (2025) — Therm and fuel-energy conversions.

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