Heat Pump Savings Calculator
Compare the annual heating cost of a heat pump against electric resistance heating using your heating load, the pump's COP, and your electricity rate.
How to use this tool
- Estimate your annual heating load in kWh of delivered heat.
- Enter the heat pump's seasonal COP (typically 2.5–4).
- Enter your electricity rate in dollars per kWh.
- Read the heat pump and resistance-heating annual costs.
- Compare the annual savings to size up the switch.
See how much a heat pump can save versus electric resistance heating. Enter your annual heating load, the pump's COP, and your electricity rate to compare operating costs and annual savings.
Formula
A heat pump moves more heat than the electricity it consumes; its COP is that multiplier. Electric resistance heating has an effective COP of 1.
Heat pump cost = (Heat load ÷ COP) × Rate
Resistance cost = Heat load × Rate
Annual savings = Resistance cost − Heat pump cost
How it works
A heat pump doesn't generate heat — it moves heat from outside air or the ground into your home, which is why it can deliver several units of heat for every unit of electricity it consumes. That ratio is the coefficient of performance (COP). A COP of 3 means the pump delivers three kilowatt-hours of heat per kilowatt-hour of electricity. Electric resistance heaters and baseboards convert electricity to heat one-for-one, an effective COP of 1.
This calculator takes your annual delivered-heat requirement in kWh, divides it by the heat pump's COP to find the electricity the pump needs, and prices that at your rate. It compares this against resistance heating, which needs the full heat load in electricity. The difference is your annual operating savings.
Real heat-pump COP varies with outdoor temperature: it falls in deep cold, so use a seasonal average (sometimes published as HSPF, which can be converted to a seasonal COP). The comparison here is against electric resistance, the most favorable baseline; savings versus an efficient gas furnace depend on local gas and electricity prices and will be smaller.
Worked example
10,000 kWh heating load, COP 3.0, $0.15/kWh
- Electricity for the heat pump = 10,000 kWh ÷ 3.0 = 3,333.3 kWh.
- Heat pump cost = 3,333.3 kWh × $0.15 = $500.00.
- Resistance heat (COP 1) cost = 10,000 kWh × $0.15 = $1,500.00.
- Annual savings = $1,500.00 − $500.00 = $1,000.00.
Heat pump cost $500.00 | Resistance cost $1,500.00 | Annual savings $1,000.00
Annual heating cost by COP (10,000 kWh load at $0.15/kWh)
| COP | Annual cost |
|---|---|
| 1.0 (electric resistance) | $1,500 |
| 2.0 | $750 |
| 2.5 | $600 |
| 3.0 | $500 |
| 3.5 | $429 |
| 4.0 | $375 |
Key terms
- Coefficient of performance (COP)
- Heat energy delivered divided by electrical energy consumed. A COP of 3 means three units of heat per unit of electricity.
- Electric resistance heating
- Heating that converts electricity directly to heat (baseboards, space heaters, electric furnaces) at an effective COP of 1.
- Heating load
- The total heat energy a building needs over a season to stay comfortable, here expressed in kWh of delivered heat.
- HSPF
- Heating Seasonal Performance Factor — a seasonal efficiency rating for heat pumps in BTU per watt-hour that can be converted to an average COP.
Frequently asked questions
- What is a good heat pump COP?
- Modern air-source heat pumps run a seasonal COP of about 2.5–4 in mild and moderate climates. Cold-climate models hold COPs above 2 even in freezing weather. Ground-source (geothermal) units reach 3.5–5.
- How do I estimate my heating load in kWh?
- If you currently heat with electric resistance, your winter electricity used for heat is already in kWh. For other fuels, convert annual heating fuel use to kWh of delivered heat (1 therm of gas at 90% efficiency ≈ 26 kWh of heat).
- Does cold weather hurt heat pump savings?
- Yes. COP drops as outdoor temperature falls, and many systems use backup resistance heat in extreme cold. Use a seasonal-average COP rather than the rated maximum for a realistic savings estimate.