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Space Heater vs Heat Pump Cost Calculator

Compare what it costs to get the same heat from a resistance heater and from a heat pump, the same way an air conditioner works in reverse.

kW
h

An assumption. Check the model’s specification sheet.

¢/kWh

Change the area above or type your own rate from your bill.

Resistance heater, per year$196.13 (1,080 kWh)
Heat pump, per year$65.38 (360 kWh)
Heat pump saves$130.75 a year

1.5 kW × 6 h × 120 days = 1,080 kWh of heat. Resistance: 1 kWh of electricity per kWh of heat. Heat pump: ÷ COP 3 = 360 kWh. × 18.16¢/kWh.

COP changes with the outside temperature and the model. Check its specification sheet.

Fig. 1 A heater against a heat pump.

Every formula is tested against worked examples. How we check

COPElectricityCost per year
COP 11,080 kWh$196.13
COP 2540 kWh$98.06
COP 3360 kWh$65.38
COP 4270 kWh$49.03

Fig. 2 The same heat at different efficiencies (COP 1 is a resistance heater).

Last checked 11/10/2026. Sources: U.S. Energy Information Administration: Electric Power Monthly, Table 5.6.A; U.S. Department of Energy: Estimating appliance and home electronic energy use.

Guide

How the cost is worked out

A resistance heater turns each kWh of electricity into 1 kWh of heat. A heat pump moves heat, so each kWh of electricity delivers several kWh of heat. That ratio is the coefficient of performance (COP). Electricity needed = heat wanted ÷ COP.

Example. 2 kW of heat for 6 hours a day over 120 days is 1,440 kWh of heat. A resistance heater uses 1,440 kWh. A heat pump with a COP of 3 uses 480 kWh, a third as much.

COP is an editable assumption

A COP of 3 is an editorial rule of thumb. Real COP changes with the outside temperature and the model; the model’s specification sheet gives its rated figure. Enter the real figure if you have it.

Using it for cooling

Air conditioners are heat pumps too. Enter the cooling you need in kW and the unit’s rated efficiency (its cooling COP, or EER divided by 3.412), and ignore the resistance comparison.

What is not included

Installation costs, insulation, ducting losses, defrost cycles and fixed charges are not included.

Common questions

Is a heat pump cheaper than an electric heater?

Per unit of heat, yes. At a COP of 3 it uses about a third of the electricity, so it would save about two thirds of the running cost.

What is a good COP?

It depends on the model and the weather. Check the specification sheet for the figure at your design temperature.

How do I know how many kW of heat I need?

A heating installer can size it from the room or home. The tool lets you try different figures.

Does this include gas?

No. It compares two electric options only.

What next?

Worked examples

Electricity rates