Protecting Our Environment

GROUND SOURCE HEAT PUMP FAQS
Frequently asked questions
Ground source systems use the ground as a means of absorbing and releasing heat. The heat pump system is extremely efficient and saves energy because the ground is at a constant temperature rather than the ambient which varies. The system is used for heating in cold weather and cooling in warm weather.
They are the integral component of the ground source system. Ground source heat pumps (GSHPs) are used to generate the cooling or heating medium. They are extremely efficient. GSHPs can give COP’s of between 4.5 and 6. Therefore for every one Kilowatt of energy used to generate heating or cooling they give in return 4.5-6kw of heating or cooling as a useable load. On the other hand a gas boiler only returns 0.9 kilowatts of useable load for every one kilowatt of energy used.
These are the means of rejecting heat or cooling from the heat pumps. They are drilled to depths of between 70m and 300m in order to obtain the load required for the specific building. The bore holes are drilled using large rotary rigs to ensure that the stability of the bore hole is maintained until the ground loop is installed.
These are used to abstract up to 20 cubic meters of water per day and do not necessitate obtaining a licence or permission for the work involved. Potable water is used as an alternative to or alongside rain water harvesting systems in order to improve water quantity and quality. The water can be used when filtered to flush toilets and also to provide water for showers. The quality of the water can be as good as drinking water in some locations depending on the geology of the area being drilled.
Once the bore hole has been drilled HDPE pipe work is installed as a means of transferring the rejected heat or cooling into the ground. The diameter varies to suit each application 32mm, 40mm or 50mm. The HDPE ground loops are very robust and have a 25 year life expectancy. They are configured in a flow and return system leading up to a chamber where they are isolated on one side and a flow measurement fitted to the other.
