Heat pump running-cost calculator

Compare a year's heating with a gas boiler against an air source heat pump. Everything runs in your browser.

Roughly your annual gas use (kWh) times your boiler efficiency.

Default assumptions: 4 kWp system costing £6,500, 50% of generation used at home, electricity 25p/kWh, export 12p/kWh. Heat pump SCOP 3.0, boiler 85% efficient, gas 6.5p/kWh, 12,000 kWh heat demand, £12,500 install less the £7,500 Boiler Upgrade Scheme grant. These are rounded 2026 UK typical figures - change any of them to match your bills and quotes.