Your home heating details
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For guidance only — not financial, tax or legal advice. Verify with a qualified professional.
Heat pump vs gas boiler — what you need to know
What is Coefficient of Performance (CoP) and what should I expect?
CoP measures how efficiently a heat pump converts electrical energy into heat. A CoP of 3.0 means for every 1 kWh of electricity consumed, you get 3 kWh of heat. Well-installed modern heat pumps in UK conditions typically achieve a Seasonal CoP (SCoP) of 2.5–3.5 — lower in older, poorly insulated homes, higher in well-insulated new builds with underfloor heating. Key point: you need the SCoP (seasonal average), not the headline rated CoP.
Why is the heat pump more expensive to run despite being efficient?
Electricity costs roughly 4–5× more per kWh than gas in the UK (Q1 2026: ~27.7p/kWh electricity vs ~6.24p/kWh gas). A heat pump needs a CoP of about 4.4 to match the running cost of a 90% efficient gas boiler at current prices. Most residential heat pumps achieve 2.5–3.5 — so they typically cost more to run, though the gap has narrowed as gas prices rose. The economics improve significantly with off-peak electricity tariffs.
What grants are available for heat pumps?
The Boiler Upgrade Scheme (BUS) in England and Wales offers £7,500 off the cost of an air source heat pump installation (as of 2026). Scotland has its own grant schemes via Home Energy Scotland. These grants can significantly change the payback calculation — factor them into your total cost comparison, not just running costs.
Does my home need insulation upgrades before a heat pump?
Heat pumps work best in well-insulated homes — they deliver lower flow temperatures than gas boilers (40–50°C vs 60–80°C) and need to run for longer to heat the same space. Draughty, poorly insulated homes are less suitable. A good installer will survey your home first. Loft and wall insulation upgrades often make more financial sense before installing a heat pump.
What about hot water — do heat pumps cover that too?
Yes — most air source heat pumps can provide both space heating and domestic hot water. However, they are less efficient at the higher temperatures needed for hot water (typically CoP 2.0–2.5 for DHW vs 3.0+ for space heating). Some households use an immersion heater for hot water top-up. Factor this into total running costs.