Ground Source Heat Pumps
(Often referred to as "Geothermal" or abbreviated to GSHP)
A heat pump is a system that uses a refrigeration-style compressor to transfer heat from outside to inside, in order to heat offices or homes. Heat pumps can take heat from the air, water or ground. Ground source heat pumps are very efficient – in fact you will get 3-4 units of heat for every unit of electricity supplied to the heatpump – if you are heating with electricity, a ground source heat pump will quarter your heating bill!!
Ground Source Heat Pumps (GSHPs) can use the ground, streams, wells or boreholes to supply the heat. Heat gained from running water or ground water is the most efficient of all.
Basic description of the component parts of a GSHP:
- A heat pump packaged unit: Water-Water type. (approx. the size of a small fridge) containing two cold water connections and two heated water connections.
- The heat source which is usually a closed loop of plastic pipe containing water with glycol or common salt to prevent the water from freezing. This pipe is buried in the ground in vertical bore holes or horizontal trenches. The trenches take either straight pipe or coiled (Slinky) pipe, buried about 1.5 to 2m below the surface. A large area is needed for this.
- The heat distribution system. This is either underfloor heating pipes or conventional radiators of large area connected via normal water pipes.
- Electrical input and controls. The system will be require an electrical input energy, three-phase being preferred, but single phase is perfectly adequate for smaller systems. A specialised controller will be incorporated to provide temperature and timing functions of the system.
