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Geothermal piles

Concrete geothermal piles are structural concrete piles which incorporate pipework for a geothermal heat exchange system.

As the concrete piles are constructed, flexible plastic pipes are incorporated within the pile reinforcement cages. Upon completion of the foundation works, the sections of pipe-work embedded in the pile are plumbed into the heating /cooling system. The concrete forming the piles provides an ideal energy transfer medium, which allows the energy derived from the ground to be used in the heating and/or cooling of the structure.

Early consultation between the specialist piling contractor, the M&E and the Structural Engineer is recommended, so that the most appropriate choices can be made in terms of piling technique, pile quantity and size, pipe-work type, pipe-work geometry and maximum depth of pipe-work achievable for the prevailing ground conditions.

Concrete geothermal piles can be installed to shallower depths than boreholes which use the traditional geothermal energy circulation systems.

The piles are connected to a ground source heat pump which simply moves heat energy from one place to another. Using the same technology as a refrigerator, the highly efficient system removes the existing heat energy stored in the earth or groundwater and transfers it into the building. Heating, air-conditioning and hot water are all derived from the same compact unit.

Typically, for every 1kW of electrical energy used to drive the heat pump, around 4kW of heat energy is delivered.

Acknowledgement: The Concrete Society