Heat Pumps

Heat Pump systems work by extracting heat from the surrounding air or ground. These systems are designed to heat a whole building and are very similar to that used in a fridge, but running in reverse.

Ground Source Heat Pumps

A few metres underneath the surface of the earth, the temperature is constant (around 15 degrees C) all year round. Ground source heat pumps make use of the ground’s constant temperature by converting and transferring this heat into a house or building, usually via radiators or underfloor heating.

They use a buried ground loop which consists of lengths of pipe buried in the ground, either in a very deep vertical hole, 50 or more metres deep, or in a shallow horizontal ditch or trench. The pipes are filled with a mixture of water and antifreeze which is pumped around the loop absorbing heat from the ground. The heat is then extracted from the liquid and used to provide heat. On average you can save £400 - £800 on your heating bills.

Air Source Heat Pumps

Air source heat pumps extract heat from the air within a building. Using a heat exchanger the heat from expelled stale air is 'exchanged' with incoming fresh cold air which is subsequently warmed to provide heat within the building. Even when the outside temperature drops, air source heat pumps can still produce 2-3 times as much energy as they use to run.

Water Source Heat Pumps

Water source heat pumps use the energy in moving water to provide heat suitable for homes or buildings. The pump system takes heat from the water and converts this into a gas. The gas is passed into a condenser that returns it to a liquid state, a process that releases heat. This newly created heat is transferred to the heat distribution system in the home or building (usually radiators or under floor heating).

Some people argue that heat pumps are not renewable because they require electricity to power the pump. However, heat pumps produce two to three times more energy output than they consume and the electricty required could be generated by a small wind turbine or PV panel.