Heat your home with energy absorbed from the ground.
Ground source heat pumps use pipes buried in the garden to extract heat from the ground. This is usually used to heat radiators or underfloor heating systems and hot water.
Beneath the surface, the ground stays at a fairly constant temperature, so a ground source heat pump can be used throughout the year – even in the middle of winter.
How does a ground source heat pump work?
A ground source heat pump circulates a mixture of water and antifreeze around a loop of pipe – called a ground loop – which is buried in the garden. Heat from the ground is absorbed into this fluid and is pumped through a heat
exchanger in the heat pump. Low grade heat passes through the heat pump compressor and is concentrated into a higher temperature useful heat capable of heating water for the heating and hot water circuits of the house. Ground loop fluid, now cooler, passes back into the ground where it absorbs further energy from the ground in a continuous process while heating is required.
The length of the ground loop depends on the size of your home and the amount of heat you need – longer loops can draw more heat from the ground, but need more space to be buried in.
Normally the loop is laid flat, or coiled in trenches about two metres deep, but if there is not enough space in your garden you can install a vertical loop down into the ground to a depth of up to 100 metres for a typical domestic home.
Heat pumps have some impact on the environment as they need electricity to run, but the heat they extract from the ground, air, or water is constantly being renewed naturally.
Unlike gas or oil boilers, heat pumps deliver heat at lower temperatures over much longer periods. This means that during the winter they may need to be left on 24/7 to heat your home efficiently. It also means that radiators should never feel as hot to the touch as they would do when using a gas or oil boiler.
The benefits of ground source heat pumps
- Can reduce your carbon footprint: heat pumps can lower your home’s carbon emissions, depending on which fuel you are replacing.
- No fuel deliveries required.
- Can provide space heating and hot water.
- Can lower fuel bills, especially if you are currently using conventional electric heating.
- It’s often classed as a ‘fit and forget’ technology because it needs little maintenance.