Heat pumps use electricity to move heat, not to create it

A heat pump is an electric appliance. It runs on the power from your home's electrical panel, the same way your refrigerator or air conditioner does. But it does not work like a space heater or electric furnace, which burn electricity to generate warmth. Instead, a heat pump uses electricity to power a compressor and fan that pull heat from outside air (or ground) and move it indoors.

This matters because moving heat takes far less electricity than creating it. A heat pump can deliver three to four units of heat for every unit of electricity it consumes. An electric furnace delivers roughly one unit of heat per unit of electricity. That efficiency difference is why heat pumps cost less to run in most climates, even though they are electric devices.

Your electric bill will go up when you install a heat pump — you are adding a major appliance to your home. But the monthly cost is usually lower than what you paid for heating with gas, oil, or electric resistance heat. The exact savings depend on your local electricity rates, your current heating fuel, and how cold your winters get.

Key Takeaways

  • Heat pumps require electricity to operate, but they move existing heat rather than generate it, making them more efficient than electric furnaces or space heaters.
  • A heat pump typically delivers three to four units of heat for every unit of electricity it uses, compared to one unit for electric resistance heating.
  • Your electricity consumption will increase after installing a heat pump, but your total heating cost usually drops because the system is so efficient.
  • The amount you save depends on your local electricity rates, what fuel you currently use for heating, and your climate zone.
  • Heat pumps work year-round — they heat in winter and cool in summer — so they replace both your furnace and air conditioner.

How much electricity a heat pump actually draws

A typical air-source heat pump (the most common type) draws between 15 and 25 amps at full capacity, depending on the model size. That translates to roughly 3,600 to 6,000 watts when running. For comparison, an electric furnace draws 10,000 to 15,000 watts, and a window air conditioner draws 3,500 to 5,500 watts.

Heat pumps do not run at full capacity all the time. Modern units modulate — they ramp up or down based on how much heating or cooling you need. On a mild day, your heat pump might run at 30 or 40 percent capacity. On the coldest day of winter, it runs harder. This variable operation is one reason they use less total energy than a furnace, which cycles on and off at full power.

The actual kilowatt-hours you consume each month depends on your climate, how well your home is insulated, how you set your thermostat, and the efficiency rating of your unit. A 3-ton heat pump in a moderate climate might use 1,500 to 2,500 kilowatt-hours per year for heating and cooling combined. Your utility bill will show the exact number.

What your electricity costs will look like

If you currently heat with natural gas, switching to a heat pump will increase your electricity bill and eliminate your gas bill. The net result is usually a savings of 20 to 50 percent on total heating and cooling costs, depending on your local rates. Gas is cheaper per unit of energy in most places, but heat pumps are so efficient that they still come out ahead.

If you currently heat with oil or propane, the savings are typically larger — often 40 to 60 percent — because those fuels are more expensive than gas. If you currently use electric resistance heat (baseboard heaters, electric furnace, or space heaters), a heat pump will lower your electric bill even though it adds a new appliance, because it is so much more efficient.

The only scenario where a heat pump costs more to operate is in a very cold climate where electricity rates are high and gas rates are very low. Even then, the difference narrows as heat pump technology improves and electricity grids shift toward cheaper renewable power. You can estimate your own costs by checking your current heating fuel bill, your local electricity rate (in cents per kilowatt-hour), and comparing them using an online heat pump calculator.

Backup heating and peak electricity use

Most air-source heat pumps include electric resistance heating as a backup. When outdoor temperatures drop below about 25 to 35 degrees Fahrenheit (depending on the unit), the heat pump becomes less efficient, and the system automatically switches on electric heating strips. These strips work like a space heater — they generate heat directly from electricity and draw significant power.

This backup heating is necessary in cold climates because a heat pump alone cannot keep up with extreme cold. But it also means your electricity use spikes on the coldest days. If you live where winter temperatures regularly drop below 20 degrees, you will see noticeably higher electric bills on those days. Some utilities offer time-of-use rates or special heat pump programs that lower the cost of this peak usage.

Ground-source heat pumps (also called geothermal) stay efficient even in very cold weather because they pull heat from the ground, which stays warmer than outdoor air. They rarely need backup heating. But they cost significantly more to install because they require drilling or trenching. Air-source heat pumps are far more common because they cost less upfront and work well in most climates.

Sizing and efficiency ratings affect your electric bill

An oversized heat pump will cycle on and off more often, using more electricity than necessary. An undersized unit will run constantly and still not keep your home warm. The right size depends on your home's square footage, insulation, window area, and climate zone. A professional load calculation determines the correct size; a rough rule is 12,000 BTU per 400 square feet, but this varies widely.

The efficiency rating also matters. Heat pumps are rated by HSPF (Heating Seasonal Performance Factor) for heating and SEER2 for cooling. Higher numbers mean lower electricity use. A unit rated HSPF 10 uses about 20 percent less electricity than one rated HSPF 8. The difference adds up over years of operation. Newer units (2023 and later) have higher minimum efficiency standards, so they use less electricity than older models.

If your current heating system is oversized or inefficient, switching to a properly sized, high-efficiency heat pump will lower your electricity use even though you are adding a new appliance. This is one reason heat pumps often reduce total energy costs despite increasing electricity consumption.

How to estimate your heat pump electricity costs

Start with your current heating bill. If you use gas, divide the dollar amount by your local gas rate (in dollars per therm) to find your annual therms consumed. Multiply by 29.3 to convert to kilowatt-hour equivalents, then multiply by your local electricity rate to estimate what that heating would cost as electricity. A heat pump uses roughly one-third that amount because of its efficiency advantage.

If you use oil or propane, the math is similar. One gallon of heating oil equals roughly 138 kilowatt-hours of heat energy; one gallon of propane equals roughly 91 kilowatt-hours. Divide your annual fuel cost by the fuel price per unit, multiply by the kilowatt-hour equivalent, then divide by 3 to account for heat pump efficiency.

For a rough check, multiply your home's square footage by 10 to 15 — that is the estimated kilowatt-hours per year per square foot for heating and cooling in a moderate climate. A 2,000-square-foot home might use 20,000 to 30,000 kilowatt-hours annually. Multiply by your local electricity rate to see the estimated annual cost. This is a ballpark figure; your actual use will vary based on thermostat settings, insulation, and weather.

Frequently Asked Questions

Will a heat pump increase my electricity bill?

Yes, your electricity consumption will increase because you are adding a major appliance. But your total heating and cooling cost usually drops because heat pumps are so efficient. If you currently heat with gas, oil, or propane, your total bill (electricity plus fuel) will likely be lower. If you currently use electric resistance heat, your electricity bill will drop even though you are running a heat pump.

Can a heat pump work in very cold climates?

Air-source heat pumps work in cold climates, but they rely on backup electric heating when temperatures drop below 25 to 35 degrees. This increases electricity use on the coldest days. Ground-source heat pumps stay efficient in extreme cold because they pull heat from the ground, but they cost much more to install. Air-source heat pumps are the practical choice for most cold-climate homes.

How much does it cost to run a heat pump for one month?

A typical heat pump uses 1,500 to 2,500 kilowatt-hours per year for heating and cooling combined. That is roughly 125 to 210 kilowatt-hours per month on average. At the U.S. average electricity rate of about 16 cents per kilowatt-hour, that is $20 to $34 per month. Your actual cost depends on your local rate, climate, and how you use your thermostat.

Do heat pumps use more electricity than air conditioners?

A heat pump and an air conditioner use similar amounts of electricity for cooling because they operate the same way in summer. The difference is that a heat pump also heats in winter, so it runs year-round. Over a full year, a heat pump uses more total electricity than an air conditioner alone, but less than an air conditioner plus a separate furnace or heater.

What is the difference between a heat pump and a space heater in terms of electricity use?

A space heater converts electricity directly into heat and uses roughly one unit of electricity per unit of heat delivered. A heat pump moves existing heat and delivers three to four units of heat per unit of electricity. Running a space heater continuously costs three to four times more than running a heat pump to heat the same space.