Heat pumps absorb heat from the outside air, heat stored naturally in the ground or heat stored in a water source. This heat can then be used to heat radiators, underfloor heating systems, or warm air convectors and hot water in your home. A heat pump extracts heat from the above sources in the same way that a fridge extracts heat from its inside. It can get heat from the air even when the temperature is as low as -15° C. 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.
A heat pump works by using the evaporation and condensing of a refrigerant to move heat from one place to another. The system is powered by a compressor, which moves the fluid around the system. The Coefficient of Performance (CoP) is the ratio of heat produced to work input. A typical heat pump will have a CoP of 3-4 meaning that for every 1kW of electricity used by the heat pump 3-4kW of heat will be supplied. A typical electrical heater has a CoP of 1, i.e. 1kW of electricity produces 1kW of heat and from this it is easy to see that using this electricity to power a heat pump is a much more efficient way to heat buildings.
Air Source Heat Pumps
Heat from the air is absorbed at low temperature into a refrigerant. This refrigerant then passes through a compressor where its temperature is increased, and transfers its higher temperature heat to the heating and hot water circuits of the house. There are two main types of air source heat pump systems. An air-to-water system distributes heat via your wet central heating system. Heat pumps work much more efficiently at a lower temperature than a standard boiler system would. This makes them more suitable for underfloor heating systems or larger radiators, which give out heat at lower temperatures over longer periods of time. An air-to-air system produces warm air which is circulated by fans to heat your home, an air-to-air system is unlikely to provide you with hot water as well.
Ground Source Heat Pumps
Heat from the ground is absorbed at low temperatures into a fluid inside a loop of pipe (a ground loop) buried underground. The fluid then passes through a compressor that raises it to a higher temperature, which can then heat water for the heating and hot water circuits of the house. The cooled ground-loop fluid passes back into the ground where it absorbs further energy from the ground in a continuous process as long as heating is required. Normally the loop is laid flat or coiled in trenches about a metre deep, but if there is not enough space in your garden you can install a vertical loops 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, the air, or water is constantly being renewed naturally.
Heat Pump Options from RES Devon
Altherma is a highly flexible, fully integrated sustainable home heating system. At the heart of the system lies an air to water heat pump that extracts heat from the outside air, raises this heat to a higher temperature and then distributes warmth around the home. Because of this advanced technology, three quarters of the heat generated by the Altherma system is completely free of charge! Daikin has more than 50 years' experience producing heat pumps and the whole system is manufactured entirely 'in house' so you can be assured of a top quality product. Furthermore, RES have a professional and highly trained design and installation team to ensure that the whole project fits your requirements and is completed successfully.