The ground absorbs heat from the sun throughout the spring and summer months.This means that, just a few feet underground, there is a fairly constant temperature of between 4 and 12oC. A ground source heat pump enables users to tap into this naturally occurring source of heat and use it in homes and buildings.

A series of pipes, containing a mixture of water and anti-freeze, is laid underground. The heat pump circulates this mixture, which absorbs the heat in the ground and carries it back to the heat pump. The mixture circulates in the pump, transferring and upgrading the heat from the ground, which can then be released into the property through underfloor heating or radiators.

Ground source heat pumps can reduce heating bills dramatically and some models can also be used as cooling units in the summer. They are low maintenance, unobtrusive and they last for years, emitting less CO2 into the atmosphere than traditional fossil fuel-based heating systems. However, they do require electricity to run and installation in existing properties can be disruptive and will require a lot of space.