£15,000 to £35,000 before grants · Up to £7,500 grant (£9,000 off gas grid) · More efficient than air source
Home › Ground Source Heat Pumps
| Typical cost | £15,000 to £35,000 (before grants) |
|---|---|
| Grant available | £7,500 via Boiler Upgrade Scheme (£9,000 off gas grid) |
| Efficiency | Higher than air source (COP typically 3.5 to 4.5) |
| Lifespan | 20 to 25 years (ground loop: 50+ years) |
| Space needed | Garden for horizontal loop, or space for a borehole |
A ground source heat pump uses a network of pipes buried in your garden to absorb heat from the ground. Even in winter, the ground a metre or two below the surface stays at a fairly constant temperature of around 10 to 12 degrees Celsius. The heat pump takes this low grade heat and concentrates it to heat your home and hot water.
There are two main types of ground loop:
The Boiler Upgrade Scheme provides £7,500 towards a ground source heat pump. If you are off the gas grid and currently heating with oil or LPG, the grant goes up to £9,000. There is no income test. Your MCS certified installer applies for the grant and it comes straight off your bill.
Home Energy Scotland offers grants and interest free loans to help Scottish homeowners install heat pumps including ground source systems. Some elements are income based while others are open to all homeowners. Contact Home Energy Scotland for the current amounts.
Northern Ireland has its own separate energy efficiency schemes. The Boiler Upgrade Scheme does not apply there. Check with the Northern Ireland Housing Executive or your local council for current support.
Ground source heat pumps work best for homes that have some garden space for the ground loop, are reasonably well insulated, and use radiators or underfloor heating. They are particularly good for larger homes or homes off the gas grid where oil or LPG costs are high.
If you have limited outdoor space, an air source heat pump may be a more practical option. Both are covered by the same grant schemes.
A ground source heat pump typically costs between £15,000 and £35,000 installed, depending on the size of your home and the type of ground loop. This is more than an air source heat pump, but ground source systems are more efficient and have lower running costs. With the Boiler Upgrade Scheme grant of £7,500 (£9,000 if you are off the gas grid), the net cost comes down significantly.
In England and Wales, the Boiler Upgrade Scheme provides £7,500 towards a ground source heat pump. If you are off the gas grid and replacing oil or LPG heating, the grant increases to £9,000. In Scotland, Home Energy Scotland offers grants and interest free loans. There is no income test for the Boiler Upgrade Scheme.
It depends on the type of ground loop. A horizontal loop needs a reasonable amount of open ground, roughly the same area as your home's footprint. A vertical borehole loop needs much less space because it goes straight down, but it costs more to install. Your installer will survey your property and advise which option works best.
Ground source heat pumps are generally more efficient because underground temperatures are more stable than air temperatures. They also tend to be quieter since the main equipment is underground or inside the house. However, they cost more to install and need either garden space for a horizontal loop or a borehole for a vertical one. For many homes, air source is the simpler and cheaper option, but ground source can be worth it if you have the space and budget.
The heat pump unit itself typically lasts 20 to 25 years, which is longer than a conventional gas boiler. The underground pipework (the ground loop) can last 50 years or more with very little maintenance. Running costs are usually lower than gas or oil, especially as energy prices rise.