Terrestrial heat probe fields
Overview

With large buildings several terrestrial heat probes - even up to some dozen - on an area can be brought in, in order to supply from the underground warmth and cold weather for the heating and/or cooling system in very effective way. The simultaneous use of several terrestrial heat probes is called a terrestrial heat probe field.

A combined system for heating and cooling

The deeper you drill into the ground, the higher the temperature. Below 20 m depth the temperature in the central country rises relatively evenly around for instance 3° C per 100m. The terrestrial heat probes (THP), installed in Switzerland are majority of the following type: 150 m a deep drilling and a heat pump supply a family house with the necessary heat energy.

Now if a series of terrestrial heat probes is united or drilling is done deeper, then the heat exchanger can access a substantially larger potential, which permits the heat supply of whole house-groups or even big buildings such as multi-family houses, industrial- and administration buildings, to hotel, multi-purpose building, etc.

For some years, terrestrial heat probe fields are used for heating or cooling systems in industrial- and administration buildings.
A series of terrestrial heat probes (4 to 80) of different depth (30 to 350 m) below the supplied building or beside the building. The lines of the individual probes are united with one or more heat pumps. Even if the plant is used for the cooling in the summer, then the drillings may have a maximum depth of 250 m, in order to avoid a too high underground temperature.

The impact of the plant is based on a yearly cycle, with which during the heating season warmth (cooling-entry into the underground) is withdrawed from the underground and during the cooling period cold weather (heat-entry) is being taken from the ground. An additionally installed boiler can be necessary thereby only during the intermediate periods and during repair work.