Heat pumps are rapidly becoming the UK’s preferred alternative to gas boilers. The government’s Boiler Upgrade Scheme offers £7,500 toward installation, making heat pumps increasingly affordable for homeowners.
This comprehensive guide covers everything you need to know: how they work, running costs, available grants, suitability for your home, and long-term savings.
What is a Heat Pump?
A heat pump is an electrical device that extracts heat from the air or ground and transfers it to your home’s heating system. Unlike gas boilers that burn fuel to generate heat, heat pumps move existing heat more efficiently.
For every unit of electricity consumed, a modern heat pump with a Coefficient of Performance (COP) of 3.0 delivers 3 units of heat. This makes them 3 times more efficient than electric resistance heating.
Types of Heat Pumps
Air Source Heat Pumps (ASHP)
Air source heat pumps extract heat from outside air, even at temperatures as low as -15°C. They’re the most common type in the UK:
- Cost: £8,000-£12,000 installed (before £7,500 grant)
- COP Rating: 2.5-3.5 (typically 3.0)
- Installation: 1-2 days, less disruptive than ground source
- Space Required: Small outdoor unit (1-1.5m x 1m), wall or ground mounted
- Best for: Most UK properties, especially newer homes
Ground Source Heat Pumps (GSHP)
Ground source heat pumps extract heat from the ground, which maintains consistent temperature year-round:
- Cost: £15,000-£25,000 installed (higher installation complexity)
- COP Rating: 4.0-5.0 (significantly more efficient)
- Installation: 2-3 weeks, requires digging (borehole or horizontal loops)
- Space Required: Requires 1,500-3,000m² of land for horizontal loops, or deep borehole
- Best for: Properties with large gardens, rural locations
How Heat Pumps Compare to Gas Boilers
| Factor | Air Source Heat Pump | Gas Boiler |
|---|---|---|
| Installation Cost | £8,000-£12,000 (- £7,500 grant) | £1,500-£3,500 |
| Lifespan | 15-20 years | 10-15 years |
| Running Cost (4,000 kWh/yr) | £295 @ 28p/kWh / COP 3.0 | £210 @ 7p/kWh (gas) |
| Annual Maintenance | £150-£200 | £100-£150 |
| Boiler Upgrade Scheme Grant | £7,500 (2026) | £0 |
Pros and Cons of Heat Pumps
Advantages
- £7,500 government grant available
- Low running costs (COP 3.0+ = 2-3x more efficient)
- No gas supply required
- Environmentally friendly (especially with renewable electricity)
- Long lifespan (15-20 years)
- Low maintenance requirements
- Can provide summer cooling (reversible systems)
- Quieter than older boilers
Disadvantages
- High upfront cost (£8,000-£18,000)
- Works best with good insulation and large radiators
- Slightly higher running costs than gas in some scenarios
- Requires electricity supply upgrade (sometimes)
- Outdoor unit noise (35-45dB typical)
- May need to upgrade radiators or underfloor heating
- Ground source requires significant garden space
- Not ideal for poorly insulated properties
Check if You Qualify for the £7,500 Grant
Get free quotes from approved heat pump installers and find out your grant eligibility.