A ground source heat pump (also known as a ground-to-water heat pump) transfers heat from the ground outside your home to heat your radiators or underfloor heating. It can also heat water stored in a hot water cylinder, ready to use for your hot taps and showers.
How does a ground source heat pump work?
Thermal transfer fluid (TTF), sometimes known as ‘brine’, is a mixture of water and antifreeze that flows around a loop of pipe buried in your garden or outdoor space. This loop could either be a long or coiled pipe buried in trenches, or a long loop (called a ‘probe’) inserted into a borehole.
Heat from the ground is absorbed into the brine, which then passes through a heat exchanger into the heat pump. This raises the temperature of the fluid and then transfers that heat to water.
See our in-depth guide to heat pumps for more information on how a heat pump works.