How much electricity does a heat pump use?

It depends on how much heat your home needs and how efficiently the system turns electricity into heat. Here is how to work out a realistic figure, with the arithmetic shown.

How much electricity does a heat pump use?

A heat pump uses electricity to move heat from the outside air into your home (see how an air source heat pump works), so it delivers more heat than the electricity it uses. Over a year, that ratio is the seasonal performance factor. Divide your home’s annual heat demand by the SPF and you have a good estimate of the electricity used.

The most useful real-world figure comes from the Electrification of Heat project, funded by the Department for Energy Security and Net Zero (DESNZ), which installed and monitored 742 heat pump systems. Across 428 air source heat pumps with a full year of good data, the median SPF was 2.78, with the middle half of homes between 2.55 and 3.05.

That figure covers the whole system, including back-up and immersion heaters, circulation pumps and defrosting, so it is a fair guide to what lands on a bill.

Heat pump kWh per year: a worked example

To turn that into kWh you need a heat demand. Ofgem’s figure for a typical household’s gas use, the medium value it uses to illustrate bills, has been 9,500 kWh a year since 1 July 2026, down from 11,500 kWh. That is gas burned, not heat delivered. SAP, the government’s method for rating the energy performance of homes, gives a condensing combi boiler (1998 or later, automatic ignition) a default winter seasonal efficiency of 84% (75% for hot water in summer) where the boiler’s own data is not available. So:

• Heat needed: 9,500 kWh × 84% ≈ 8,000 kWh a year for heating and hot water.
• Electricity at the trial median: 8,000 ÷ 2.78 ≈ 2,878 kWh a year.
• Cost at 26.32p per kWh: 2,878 kWh × 26.32p ≈ £757 a year.

An illustration, not a quote: our arithmetic using Ofgem’s medium typical gas use (from 1 July 2026), SAP 10.3’s default condensing combi efficiency, the Electrification of Heat SPFs and Ofgem’s price cap for 1 October to 31 December 2026 (26.32p per kWh, GB average, Direct Debit, single rate). Ofgem’s gas figure may include gas for cooking, and SAP’s summer figure is lower than 84%, both of which would pull the heat figure down; a boiler more efficient than SAP’s default would push it up. Treat 8,000 kWh as a round example. Standing charges are left out. The other rows are example heat demands, not typical figures. The next cap period starts on 1 January 2027.

To estimate your own, take your annual gas use in kWh from your bills or supplier account, multiply by your boiler’s efficiency, and divide by the SPF your installer designs for.

Heat pump running cost per day and per month

Spread evenly, the example’s 2,878 kWh of electricity works out at about 7.9 kWh a day, or £2.08 a day and £63 a month at the October–December 2026 cap. In practice it is never spread evenly: a winter month costs much more than a summer one (see below), so budget on the annual figure rather than a single month’s bill.

Two other things affect the bill:

• The electricity standing charge is 54.83p a day (about £200 a year) at the current cap. You pay it with or without a heat pump, so it is not a heat pump cost.
• The gas standing charge (29.68p a day at the current cap) stops only if you remove gas from the home altogether. The Energy Saving Trust suggests considering removing other gas appliances when you replace a gas boiler for exactly this reason.

Does a heat pump use a lot of electricity?

Compared with anything else in most homes, yes. Ofgem’s typical household uses 2,500 kWh of electricity a year on a standard single-rate meter. In the example above, the heat pump would use a little more than that again. One network operator, SP Electricity North West, puts it plainly: heat pumps “can use as much electricity as a domestic power shower, but for much longer”.

But it replaces the fuel you burned before. The Energy Saving Trust says that replacing a gas or oil boiler means “your electricity costs will increase significantly” while your gas or oil costs fall significantly. Replacing storage heaters is the reverse (see heat pump vs electric heating). Against gas, the overall result depends on efficiency and tariff; our heat pump vs gas boiler running costs page works through it.

Heat pump electricity use in winter and summer

A heat pump uses far more electricity in winter than in summer. As the trial report puts it, the heat demands of buildings are highest when it is coldest outside, and that is also when an air source heat pump is least efficient.

• Efficiency falls as it gets colder. Across the trial’s air source heat pumps, the median whole-system efficiency in each half-hour was 3.37 at around 10°C outside, 2.57 at 0°C and 2.32 at −6°C.
• A cold day, roughly. Across the trial’s air source heat pumps, the median half-hour at around 0°C, while they were running, used 0.59 kWh of electricity. If that went on for all 48 half-hours of a 0°C day, it would be about 28 kWh, or roughly £7.50 at the current cap. That is our rough scaling, not a figure for your home or for the worked example above: it assumes the heat pump runs in every half-hour, and the report notes its half-hourly medians average over thousands of half-hours in homes of different sizes and should not be used to work out peak demand.
• Summer is mostly hot water. With little or no space heating, the heat pump runs less often. The trial report notes that in summer it may run “less frequently and less efficiently to produce hot water”, but the total used is far lower.
• Defrosting. The outdoor unit periodically defrosts in cold weather, which uses energy. The trial’s SPFs already include it, and the MCS design standard says an air source system should keep the home at its design temperatures across multiple defrost cycles.

For more on cold-weather performance, see do heat pumps work in cold weather?

What changes how much electricity it uses

The same heat pump can use very different amounts of electricity in different homes. The main levers:

• Heat loss and insulation. Less heat lost means less heat to replace, and the trial’s householder guide says heat pumps work most efficiently in a well-insulated home. In a poorly insulated one, the Energy Saving Trust says you are likely to need bigger radiators; see do I need new radiators for a heat pump?
• Flow temperature and weather compensation. The cooler the water sent to your radiators, the more efficient the heat pump: across the trial’s heat pumps, the median efficiency of the heat pump unit itself was 3.50 at a 35°C flow temperature and 2.38 at 55°C. The Energy Saving Trust says a weather compensation curve that is not set correctly can increase your running costs.
• Thermostat setpoints. The trial’s guide says a lower room temperature makes the heat pump work more efficiently and use less energy, and suggests setting it back a few degrees overnight or when you are out rather than switching it off.
• Hot water use and temperature. Heat pumps are more efficient at lower temperatures, and more hot water means more electricity, however your hot water is provided.
• Legionella cycles. Stored hot water is periodically heated above 60°C to prevent bacterial growth; in the trial homes, an in-built immersion heater did this. The Energy Saving Trust says high bills may mean it runs too often; for most people weekly is safe.
• Back-up heaters. Some heat pumps use an electric booster in the coldest spells. The Energy Saving Trust says that should not add much over a year, but needing it regularly may mean radiators are too small or the heating curve is wrong.

Our guide to running a heat pump efficiently covers the settings in detail, and heat pump maintenance covers the upkeep.

Does a heat pump need a bigger electricity supply?

That depends on your existing supply, and it has to be checked. Every heat pump installation has to be reported to the local distribution network operator (DNO). MCS explains that where the home’s new maximum demand is 60 amps or less and the other criteria are met, the installer can connect and then notify the DNO within 28 days. Between 60 and 100 amps, the installer must apply before installing, and the DNO assesses the supply within 10 working days.

SP Electricity North West advises asking your installer to confirm your supply is adequate, and says most domestic customers face no charge for the connection, though a larger heat pump may need a supply upgrade that could incur a cost. Your survey should tell you before any work starts.

Solar panels and tariffs

Solar panels can cover some of a heat pump’s electricity, but the timing works against them. The Energy Saving Trust notes you will be selling surplus electricity in summer and buying it back to run the heat pump at night and in winter, and that you cannot store summer surplus for winter heating. See heat pumps and solar panels.

Time-of-use tariffs charge less at some times and more at others. The Energy Saving Trust says one may let you set hot water, and maybe space heating, to use the cheaper hours, but you could still be better off on a standard tariff. It also says Economy 7 does not suit heat pumps, which often run through the more expensive daytime rate. Compare tariffs on your own pattern of use rather than a headline rate.

How a survey works out your figure

A proper design starts with a heat loss calculation. The MCS heat pump design standard, MIS 3005-D, requires the heat pump to meet at least 100% of the calculated heat load without help from any supplementary electric heater, and requires the installer to be given each room’s heat loss, the daily hot water demand, the design flow temperature and the expected seasonal efficiency. Those are the numbers you need to estimate your electricity use, but treat the design efficiency with some caution: in the trial, measured efficiency came in below the design figure in 91.9% of the homes compared. See what size heat pump do I need?

What a heat pump costs to install depends on your property: the size of system its heat loss calls for, whether radiators or pipework need upgrading, where the outdoor unit goes and how long the pipe run is, how hot water will be provided, and any electrical work. Get in touch and we will arrange a free survey of your home and give you a clear, itemised quote; if you are happy with it, we can go ahead. See also our heat pump cost guide.

On the grant: you may be eligible for £7,500 towards an air source heat pump in England or Wales through the Boiler Upgrade Scheme if you own the property. An MCS-certified installer applies and takes it off your quote, and an air source voucher lasts three months from the date it is issued. Insulation stopped being a scheme requirement on 8 May 2024, and an EPC stopped being needed on 28 April 2026 — but insulation still affects how much electricity your heat pump uses. ByEco’s own MCS certification is in progress, so we cannot apply for the grant yet (see below).

What to ask an installer, and where ByEco stands

• What is my home’s calculated heat loss and annual heat demand?
• What flow temperature is the design based on, and what seasonal efficiency do you expect at it?
• So roughly how many kWh of electricity a year should I expect, and what is that on my tariff?
• How will hot water be provided, and how often will the legionella cycle run?
• Is my electricity supply adequate, and will you notify the network operator?

ByEco installs air source heat pumps in England and Wales. Our MCS and TrustMark certification is in progress, so we cannot yet apply for the Boiler Upgrade Scheme grant for you. If you want a realistic idea of what a heat pump would use in your home, talk to us.

Sources

Every figure on this page was checked against primary sources on 14 October 2026. Grant rules, planning rules and prices change — if you are reading this much later, verify before acting.

• Energy Systems Catapult for DESNZ — Electrification of Heat Demonstration Project: Heat Pump Performance Data Analysis Report (December 2024)
• Energy Systems Catapult — Electrification of Heat: low temperature air source heat pump user guide
• Ofgem — Review of typical domestic consumption values: decision (27 May 2026)
• Ofgem — Energy price cap unit rates and standing charges: 1 October to 31 December 2026
• BRE for DESNZ — SAP version 10.3, Table 4b: Seasonal efficiency for gas and liquid fuel boilers (12 June 2026)
• Energy Saving Trust — Your heat pump questions answered (last updated 27 May 2026)
• Energy Saving Trust — The most efficient way to run a heat pump (last updated 19 May 2026)
• MCS — MIS 3005-D:2025 The Heat Pump Design Standard, Issue 2.0 (5 December 2025)
• MCS — Notifying DNOs
• SP Electricity North West — Heat pumps
• GOV.UK — Apply for the Boiler Upgrade Scheme: what you can get
• legislation.gov.uk — Boiler Upgrade Scheme (England and Wales) Regulations 2022, regulation 15
• Ofgem — Boiler Upgrade Scheme guidance for installers V5.1