Geothermal heat pump

Ground source heat pumps (geothermal or brine-to-water heat pumps) utilise the constant heat of the ground to heat heating and domestic hot water. They are particularly efficient and are often used in new builds.

A liquid mixture, known as brine, circulates through ground collectors or geothermal probes and absorbs the stored geothermal heat. In the heat pump, the refrigerant vaporises, is brought to higher temperatures by the compressor and then transfers the energy to the heating water. Once the heat has been released, the refrigerant liquefies again and the cycle begins anew. Thanks to the stable ground temperatures, heat can also be reliably recovered in winter.

The heat source is the ground, the heat is transferred to the heating and domestic hot water. The efficiency is high as the ground temperatures are stable all year round. Brine-to-water heat pumps are particularly suitable for new builds or larger renovation projects, require sufficient land area for ground collectors or boreholes and are subject to authorisation. The technology is very efficient and delivers consistently high heating outputs. However, the installation costs are higher than for air-water systems, as geothermal probes or collectors have to be laid. The combination with well-insulated buildings and an efficient heating system maximises energy savings.