How many watts does a heat pump use?
A central air-source heat pump uses about 1,500 to 5,000 watts while the compressor and the air handler blower are running, and the figure tracks the system's tonnage closely. A 2-ton unit (common on a small or tight home) runs near 1,500 to 3,000 watts, a 3-ton near 2,500 to 4,000 watts, and a 4 to 5-ton unit near 3,500 to 5,000 watts. The indoor air handler's blower motor adds roughly 400 to 800 watts on top of the compressor when it is a separate figure. These are planning ranges: published numbers disagree, so read the MCA (minimum circuit ampacity) on the nameplate or the manufacturer's data sheet for your exact unit rather than trusting a rule of thumb.
A ductless mini-split draws much less per head, about 500 to 2,000 watts. A 9,000 BTU head runs near 600 to 800 watts, a 12,000 BTU head near 900 to 1,200 watts, and an 18,000 to 24,000 BTU head near 1,200 to 2,000 watts. Small single-zone mini-splits run on a 120-volt circuit; larger ones and multi-zone systems are 240 volts. Mini-splits use an inverter-driven compressor that ramps its speed up and down instead of cycling fully on and off, so the real draw glides between a low idle and the figures above rather than slamming to peak.
A geothermal (ground-source) heat pump draws a similar compressor load to an air-source unit, in the 3,000 to 6,000-watt range for a whole home, but it holds its efficiency through the cold because it pulls heat from the stable ground rather than frozen air. Whichever type you have, the compressor is a motor, so a conventional single-speed unit has a startup surge of 2 to 3 times its running watts. Inverter-driven mini-splits soft-start and barely surge, which matters a lot for generator and inverter sizing. To size a system against your roof's output, start with the solar panel calculator.
Why does a heat pump use less electricity than electric heating?
Because a heat pump moves heat instead of generating it. An electric baseboard, a space heater, or the heat strips in a furnace are resistance elements: every watt of electricity becomes one watt of heat, a coefficient of performance (COP) of exactly 1.0. A heat pump runs a refrigeration cycle that collects heat already in the outdoor air (even cold air holds heat) and pumps it indoors, so each watt of electricity delivers three to four watts of heat in mild conditions, a COP of 3 to 4. That is why swapping resistance heat for a heat pump cuts heating electricity by roughly two-thirds.
This is the whole case for a heat pump and the reason it is the center of home electrification. A 1,500-watt resistance space heater and a heat pump delivering the same heat are not close on the bill: the heat pump does the job on roughly 400 to 600 watts of input in good conditions. The same logic is why a heat-pump water heater and a heat-pump clothes dryer use a fraction of the energy of their resistance cousins. You are paying to run a pump, not to burn electricity directly into heat.
The catch is that COP is not a fixed number. It is highest when the outdoor temperature is close to the indoor temperature and falls as the gap widens, which is exactly why winter wattage is the part worth understanding in detail.
How much electricity does a heat pump use in winter?
A heat pump uses more electricity in winter than in summer in most climates, for three reasons stacked on top of each other. The heating load itself is larger than the cooling load, the COP drops as it gets colder (a standard unit that holds a COP near 3 to 4 at 47 degrees can fall to 1.5 to 2.5 around 17 degrees, while cold-climate models hold closer to 2 to 3), and below a certain outdoor temperature the backup electric resistance heat strips switch on to keep up.
Those heat strips are the winter bill spike. They are plain resistance elements rated at 5,000 to 20,000 watts (5 to 20 kW), so when they run, the system briefly draws like an electric furnace and the COP for that portion drops to 1.0. They engage below the system's balance point, during the defrost cycle, and when a thermostat recovers from a big overnight setback all at once. The practical lever: a cold-climate (inverter) heat pump leans on the strips far less, and holding a steadier thermostat instead of deep setbacks keeps the strips from firing on recovery.
Over a heating season, a whole-home air-source heat pump commonly uses roughly 2,000 to 6,000 kWh depending on climate, home size, and insulation, which at the 2026 US average near $0.17 per kWh is a rough $340 to $1,000 for the season (an estimate, not a quote; your rate and weather move it a lot). In an all-electric home the heat pump is often the single largest line on the yearly bill. The kW vs kWh and watts to kWh explainers untangle why a 3,000-watt unit does not mean 3,000 watts every hour.
How much amperage does a heat pump use, and what circuit does it need?
A central air-source heat pump typically needs a dedicated 240-volt circuit of 20 to 60 amps, set by the unit's size. The outdoor condenser draws the compressor load, and the indoor air handler (with its blower and any backup heat strips) usually gets its own separate circuit, which is often the larger of the two because 5 to 20 kW of resistance strips can need a 30 to 60-amp or bigger feed on their own. The exact size is printed on the nameplate as MCA (minimum circuit ampacity) and MOP (maximum overcurrent protection); size the wire and breaker to those numbers, not to a guess.
A ductless mini-split is lighter: a small single-zone head runs on a 15 to 20-amp circuit (120V on the smallest units, 240V on most), and a multi-zone system on a 20 to 30-amp 240V circuit. Because the compressor is a motor, the breaker allows for the inrush, which is why you read the MOP rather than dividing watts by volts.
Installing or resizing any of this means working at 240 volts inside the service panel, often adding a large circuit for the heat strips, which is licensed HVAC and electrician territory with a permit, the same as wiring an electric dryer or a 240V water heater circuit. Adding a big heat-pump circuit on top of an existing panel can also push a 100 or 150-amp service over its limit, so a load calculation comes first.
Is it cheaper to run an AC or a heat pump?
In cooling, they cost about the same, because a heat pump is an air conditioner. Both run the identical vapor-compression cycle; the heat pump just adds a reversing valve so it can run that cycle backward for heat in winter. A heat pump and a straight AC of the same SEER2 efficiency rating use the same electricity to cool a given house, so there is no cooling penalty for having the heating ability. Our can solar power an air conditioner guide covers the cooling-side wattage and panel sizing for window, mini-split, and central units in detail.
The question usually really means heating, and there a heat pump wins decisively against electric heat and often against gas. Against baseboard, resistance furnace strips, or a space heater, the heat pump's COP of 3 to 4 makes it roughly a third the cost for the same warmth. Against a gas furnace it depends on local electricity and gas prices, but modern heat pumps are frequently competitive or cheaper, and they avoid burning fuel on site.
So the honest answer to 'AC or heat pump' is that for cooling it is a wash, and for heating the heat pump is far cheaper than any electric resistance alternative. The only time a heat pump's heating gets expensive is when it falls back on its resistance strips in deep cold, which is the scenario the winter section above is about.
Can you run a heat pump on solar or a battery?
On a grid-tied system, yes, and a heat pump is a good solar match for cooling: the air conditioning load peaks on hot sunny afternoons exactly when the panels are producing the most. The realistic approach is to size the array to offset the heat pump's annual kWh and let net metering balance the hours when it runs after dark, rather than trying to power each moment directly. Size that honestly with the solar panel calculator, since a heat pump is often the biggest single load on the whole house.
Off-grid or on battery backup, a heat pump is a demanding load. The compressor's 2 to 3 times startup surge (on a single-speed unit), its sustained draw, and the 240-volt supply put a central unit out of reach of a small portable power station. A 100Ah, 12-volt battery holds only about 1 kWh, which a 3,000-watt central unit would drain in well under half an hour, and its inverter usually cannot make 240 volts anyway; our what a 100Ah battery can run breakdown shows the much lighter loads that size suits. A large 240V home battery or a big solar generator can run an inverter mini-split for a while, and an inverter-driven mini-split is the most battery-friendly option because it soft-starts and modulates down.
The one thing you should not try to run off a battery is the resistance heat strips: 5 to 20 kW of pure resistance heat will flatten any realistic battery in minutes. In winter, when sun is scarce and heating load is highest, the grid or a fuel generator carries the heat pump far more sensibly than a battery. Pair the heat pump with solar for the annual offset and the summer match, and plan backup around the mini-split or the lighter loads, not the whole central system in a cold snap.
Frequently asked questions
What is the average daily kWh usage for a 2000 square foot house?
A typical 2,000 square foot US home uses roughly 20 to 40 kWh a day, averaging around 30, though all-electric homes and hot or cold climates run higher. Heating and cooling is the largest slice, and a heat pump is usually the single biggest load in that slice: it might use a few kWh a day in mild weather and 20 to 40 kWh a day on its own during a cold snap when the backup resistance strips run. Our how many watts to run a house breakdown and the solar panel calculator show where a heat pump sits against everything else on the panel.
Is it cheaper to run an AC or a heat pump?
For cooling they cost the same, because a heat pump is an air conditioner running the same refrigeration cycle; at equal efficiency ratings they use equal electricity to cool. The difference is heating. A heat pump heats at a coefficient of performance of 3 to 4 in mild weather, so it costs roughly a third of what electric baseboard or furnace resistance heat costs for the same warmth, and it is often competitive with or cheaper than gas. A heat pump only gets expensive to heat with when it falls back on its electric resistance strips in deep cold.
How much electricity does a heat pump use in winter?
More than in summer in most climates. The heating load is bigger than the cooling load, the heat pump's efficiency drops as it gets colder (a standard unit can fall from a COP near 3 to 4 at 47 degrees to 1.5 to 2.5 around 17 degrees, while cold-climate models hold closer to 2 to 3), and below a balance-point temperature the backup resistance heat strips switch on and briefly pull 5,000 to 20,000 watts. A whole-home air-source heat pump commonly uses about 2,000 to 6,000 kWh over a heating season, with the strips driving the cold-snap spikes. A cold-climate model and steady thermostat settings keep the strips from firing as often.
How much amperage does a heat pump typically use?
A central air-source heat pump usually sits on a dedicated 240-volt circuit of 20 to 60 amps depending on size, with the indoor air handler and its backup heat strips often on a separate, sometimes larger, circuit because 5 to 20 kW of resistance strips can need a 30 to 60-amp feed. A ductless mini-split is lighter, 15 to 20 amps for a single head (120V on the smallest, 240V on most) and 20 to 30 amps for a multi-zone system. Read the MCA and MOP figures on the nameplate rather than dividing watts by volts, because the breaker has to allow for the motor's inrush.
Can a portable power station or generator run a heat pump?
A mini-split, often yes; a whole central system with its heat strips, usually no. An inverter-driven mini-split head draws only 500 to 2,000 watts and soft-starts, so a large 240V-capable power station or a mid-size generator can run one. A central air-source unit draws 1,500 to 5,000 watts with a 2 to 3 times startup surge on single-speed compressors and needs 240 volts, which pushes it past small portable units. The resistance heat strips, at 5 to 20 kW, are not realistic to run off any battery. For backup, plan around a mini-split or the lighter loads in the house, and lean on the grid or a fuel generator for central heating in a cold snap.