GROUND SOURCE HEAT PUMPS GSHP RENEWABLE SYSTEMS AND ENERGY POWER GENERATION

Ground source heat pumps (GSHP) generate power by heat transfer from the ground into a building to provide space heating and, in some cases, to pre-heat domestic hot water.

They operate like a refrigerator in reverse. This method of energy production is not to be confused with geothermal. The sub surface of the ground is always at about the same temperature, unlike the surface, and this differential can be used to generate heat.

This is a good system to fit if you are prepared for major works around the outside of the house, and want a new heating system. The system comprises three parts:

• a ground loop - this is pipe laid in the ground, either in a trench or down a borehole. It is a closed circuit and is fulled with an anti-freeze type liquid
• a heat pump - this is similar to the pump in your fridge
• heat distribution system - to get the heat into the boiler or into the heating system

A typical 6 - 8kW system costs 7,300-11,800 GBP plus the price of connection to the distribution system, which will vary with property and location.

The payback time can be quite fast, especially if you are off grid for gas, and would have to use oil. Quotes come in with 75% savings, and threefold reduction in normal energy bills.

It is estimated that using a ground source heat pump can save between 400-800 GBP per year, which also saves 2-6 tonnes of carbon emissions.