How Much Electricity Does a Heat Pump Use in the UK? Running Costs & Savings 2026
An air source heat pump (ASHP) in a typical UK home uses 3,000 to 5,000 kWh of electricity per year, costing £1,020 to £1,700 at the current 34p/kWh rate. Despite electricity being more expensive than gas per kWh, heat pumps are 3-4x more efficient (COP of 3-4), meaning they produce 3-4 kWh of heat for every 1 kWh of electricity consumed. This makes them £200-600 cheaper annually than a gas boiler for most homes.
Heat Pump Efficiency: COP Explained
The Coefficient of Performance (COP) measures heat pump efficiency. A COP of 3.5 means the heat pump produces 3.5 kWh of heat for every 1 kWh of electricity. Typical ASHPs achieve COP 2.5-4.0 depending on outside temperature: Mild weather (10°C): COP 4.0+ — most efficient. Average winter (5°C): COP 3.0-3.5 — typical UK winter performance. Cold snap (-5°C): COP 2.0-2.5 — still more efficient than direct electric heating. Seasonal Performance Factor (SPF) averages COP across the year — typically 2.8-3.5 in the UK. Ground source heat pumps (GSHP) achieve SPF 3.5-4.5 as ground temperature is more stable.
Annual Running Cost Calculation
A typical 3-bed semi-detached house needs approximately 12,000 kWh of heat per year. With a gas boiler (90% efficiency): 12,000 ÷ 0.90 = 13,333 kWh gas × 6.76p = £901/year + standing charge. With an ASHP (COP 3.0): 12,000 ÷ 3.0 = 4,000 kWh electricity × 34p = £1,360/year. With an ASHP (COP 3.5): 12,000 ÷ 3.5 = 3,429 kWh × 34p = £1,166/year. At current UK prices (gas 6.76p, electricity 34p), heat pumps are slightly more expensive than gas. However, with solar panels or off-peak electricity (15p/kWh), heat pump costs drop dramatically.
Heat Pump + Solar: The Winning Combination
Pairing a heat pump with a 4kW solar system transforms the economics. Solar generates ~3,400 kWh/year, offsetting most of the heat pump electricity during spring/summer/autumn. Estimated combined annual heating cost: £400-700/year — half the cost of gas. With a battery (storing excess solar for evening heat pump use), costs drop further to £200-400/year. The BUS grant (£7,500) covers much of the heat pump cost, and solar is 0% VAT. Combined payback: 5-8 years for the whole system.
BUS Grant and Financial Incentives
The Boiler Upgrade Scheme (BUS) provides £7,500 towards an air source heat pump or £7,500 towards a ground source heat pump. A typical ASHP installation costs £8,000-14,000, so the grant covers 50-90% of the cost. Requirements: your home must have an EPC certificate, the existing boiler must be fossil fuel (gas, oil, LPG), and the installation must be by an MCS-certified installer. The grant is applied at point of sale — your installer deducts it from the invoice. No repayment required.
| Heating System | Annual kWh Input | Rate | Annual Cost |
|---|---|---|---|
| Gas Boiler (90%) | 13,333 kWh gas | 6.76p/kWh | £901 |
| ASHP COP 3.0 | 4,000 kWh elec | 34p/kWh | £1,360 |
| ASHP COP 3.5 | 3,429 kWh elec | 34p/kWh | £1,166 |
| ASHP + Solar | 2,000 kWh elec | 34p/kWh | £680 |
| ASHP + Off-Peak | 3,429 kWh elec | 15p/kWh | £514 |
Is a Heat Pump Right for Your Home?
Heat pumps work best in: well-insulated homes (EPC C or above) — good insulation keeps heat in and allows lower flow temperatures. Underfloor heating or large radiators — heat pumps are most efficient at low flow temperatures (35-45°C vs 60-80°C for gas boilers). Homes that need work first: poorly insulated homes — insulate before installing a heat pump. Small radiators — may need upsizing for lower flow temperatures. Listed buildings — external ASHP units may need planning consent. Get an EPC assessment and heat loss calculation before committing. Many installers offer free surveys.
Disclaimer: For educational reference only. Consult a licensed professional.