8 kW Air Source Heat Pump running cost — Domestic hot water only (2 h)
A 8 kW Air Source Heat Pump (COP 2.7, BEIS data) draws 2.96 kW of electricity per hour. Running 2 hours/day uses 5.9 kWh and costs £1.55/day at the Ofgem cap of 26.11p/kWh (1 July to 30 September 2026).
8 kW Air Source Heat Pump — Domestic hot water only (2 h): 8 kW ÷ COP 2.7 = 2.96 kW electricity draw × 2 h = 5.9 kWh/day = £1.55/day. Weekly: £10.83. Annual: £564.75. Context: Summer use, hot water production only. Source: DESNZ/BEIS (OGL v3.0) + Ofgem.
- Per day
- £1.55
- Per week
- £10.83
- Per month
- £47.06
- Per year
- £564.75
System specification
- Heat output
- 8 kW
- Type
- Air-source (ASHP)
- Seasonal COP
- 2.7
- Electricity draw
- 2.96 kW/h
- Daily kWh
- 5.9 kWh
- Scenario
- 2 h/day
BEIS Heat Pump Information Note 2024 — 8 kW ASHP, typical SCOP 2.7 for UK climate
How the cost is worked out
- Electricity draw per hour: 8 kW ÷ COP 2.7 = 2.96 kW.
- Daily kWh: 2.96 kW × 2 h = 5.9 kWh.
- Daily cost: 5.9 kWh × 26.11p/kWh = £1.55.
- Weekly: £1.55 × 7 = £10.83.
- Annual: £1.55 × 365 = £564.75.
Get a heat pump installation quote
A MCS-certified heat pump installer can assess your home and give you a detailed cost and savings estimate. GeraHome connects you with qualified HVAC engineers.
Find a heat pump installerSame scenario — other systems
Track heat pump running costs
Updated each time the Ofgem cap changes. No spam.
No spam. Unsubscribe anytime. A Gera Services product.
COP 2.7 from DESNZ/BEIS — Heat Pump Information Note: Seasonal Performance Data 2024 (OGL v3.0). Unit rate 26.11p/kWh from Ofgem — Energy price cap unit rates and standing charges (1 July to 30 September 2026).