Geothermal heat pumps use the ground as a heat source, because even a few metres below the surface the ground temperature is constant all the year round
The ground stays at a fairly constant temperature under the surface, so the heat pump can be used throughout the year – even in areas with harsh winters.
The research into the thermal field has lead to the development of technology and heat pumps which are especially designed to adapt to every kind of soil.
The heat extraction and release from the ground can be used to heat, cool and supply domestic hot water. The efficiency of the system is 4 times higher than the electrical absorption.
The exchange of heat is guaranteed by horizontal and vertical loops. They usually involve a system of polyethylene pipe where a thermal fluid composed of water and glicole flows through them in a closed circuit. This circulating fluid is an antifreeze solution. Different kinds of loops are available in order to meet the requirements of different plants. Geothermal loops can be divided into horizontal and vertical loops.
Geothermical horizontal loops
Horizontal loops require a greater amount of land surface area but they are less expensive to install. Horizontal loops are laid in trenches, typically at a depth of 1 – 1.5m. They usually require a land surface area which is 2.5 – 3 times bigger than the area that needs to be cooled. In summer the requested land surface area could be even bigger.
Geothermal vertical loops
The geothermal vertical loop allows the heat pump to use the energy from a ground source, where the temperature is constant throughout the year, with great benefits in terms of costs’ reduction.. Vertical loops are generally considered when the available land area is limited. Wells are bored to depths around 100m in order to reduce the pumping power and increase the efficiency of the system.