Heat Pump Running Cost Calculator Trending

Heat pumps extract heat from outdoor air (air source) or the ground (ground source) and deliver it to your home. They are highly efficient, producing 2.5-4 units of heat for every unit of electricity consumed. This ratio is the Coefficient of Performance (COP). A heat pump with a COP of 3 produces 3 kWh of heat for each 1 kWh of electricity used.

An air source heat pump (ASHP) typically costs £8,000-£15,000 installed, while a ground source heat pump (GSHP) costs £15,000-£35,000 including ground works. The Boiler Upgrade Scheme provides a £7,500 grant towards the cost of an ASHP or GSHP, reducing the upfront cost significantly.

Running costs depend on your electricity tariff and the heat pump's seasonal COP (SCOP). At 24.5p/kWh electricity and a SCOP of 3, the effective heating cost is 8.2p per kWh of heat — compared to 7.5p per kWh for a 90% efficient gas boiler at 6.76p/kWh gas. Heat pumps become more cost-effective on low-rate tariffs or paired with solar panels.

How heat pumps work. Air source heat pumps extract heat from outside air (works down to -15°C) using a refrigeration cycle. For every 1 kWh electricity used, deliver 3-4 kWh heat (COP / Coefficient of Performance). Ground source heat pumps: COP 4-5, but installation £20-£30k. Hybrid heat pumps work alongside existing gas boilers — good transitional option. UK Boiler Upgrade Scheme grants £7,500 toward heat pump installation (extended to 2028).

Heat pump running costs vs gas boiler. Gas boiler: 90% efficiency × £0.06/kWh gas = £0.067 per kWh heat. Heat pump: COP 3.5 × £0.24/kWh electricity = £0.069 per kWh heat. Roughly EQUIVALENT on standard tariffs. With time-of-use tariff (Octopus Cosy: cheap morning + evening, expensive midday): heat pump 20-30% cheaper. Heat pump + solar PV: heat pump runs near-free in summer (less heating need anyway). Insulation matters: poorly-insulated homes cost much more to heat regardless of source.

Cost to install and grants. Air source heat pump: typical £10-£15k installed (5-bed house £12-£18k). Boiler Upgrade Scheme: £7,500 grant. Net cost: £3-£8k for typical homes. Compared to new gas boiler £3-£4k, heat pump costs £1-£5k more. Operating savings + grant payback in 5-15 years depending on tariff and insulation. Government's Heat in Buildings strategy aims to phase out new gas boiler installations from 2035 — heat pumps becoming mainstream.

Requirements and limitations. Outdoor unit: 0.8m × 1.0m × 0.6m space, ideally 1m from boundary. Indoor: cylinder needed (heat pumps work best with hot water tank vs combi). Larger radiators (1.5-2× current size) needed in poorly-insulated homes — adds £1-£3k cost. Underfloor heating particularly suits heat pumps (low flow temp 35-45°C vs 65-75°C radiators). Noise: 40-60 dB at 1m — quieter than gas boiler in most homes. Some Permitted Development rights (England) for installations under 0.6m³ from boundaries.