Brine/water heat pump
STORED HEAT FROM THE EARTH
The brine/water heat pump, also called a ground source heat pump, draws its energy from the ground. Harnessing the heat from the earth and using it for heating is the idea behind brine/water heat pumps. The great advantage of the ground as a heat supplier is its constant temperature: In summer and winter, the temperature below ground in our latitudes is around 8-10 degrees. The geothermal heat can be utilised by different systems: Brine/water heat pumps extract the heat energy by means of ground probes or ground collectors, water/water heat pumps by means of well systems.
How does a brine/water heat pump work?
The brine/water heat pump uses the earth's heat to make advantageous use of thermal energy for heating and hot water systems. The actual heat pump is located above the earth's surface. To supply the brine-to-water heat pump with thermal energy, either ground probes or ground collectors are used in practice.
A refrigerant with a low boiling point circulates in the brine/water heat pump and absorbs the heat from the ground. The evaporator heats the refrigerant from a liquid to a gaseous state. The compressor raises the temperature further by reducing the volume and compressing the refrigerant vapour. When the refrigerant has reached the required temperature, it is fed to the heat exchanger and then transfers the heat to the heating system. The cooled refrigerant becomes liquid again and loses the remaining pressure through the expansion valve that transports the refrigerant back to the evaporator.
Brine/water heat pumps with ground sondes (deep drilling)
One or more boreholes are required for a geothermal probe system. The number and depth of the boreholes depend on the soil conditions and your energy requirements, which the heat pump must provide for heating. The geothermal probes are inserted vertically into the ground to a depth of 100 metres. The brine circulating in the pipe can then be collected and transported to the heat pump.
Brine/water heat pumps with ground collectors
The ground collectors are laid horizontally and in loops at an average depth of one metre in the ground. A mixture of water and environmentally friendly antifreeze absorbs the geothermal heat and transfers it to the heat pump via a heat exchanger.
Advantages of brine/water heat pumps
- Earth as an energy source is almost inexhaustible, climate-friendly and available free of charge. The electricity required corresponds to about a quarter of the energy extracted.
- Especially in winter, geothermal heat as an energy source is a particularly efficient way of using environmental energy, as the temperature in the ground is constantly around 8-10 degrees all year round.
- There are several extraction systems available for the brine/water heat pump to use geothermal energy: Ground probes, ground collectors, trench collectors, ground baskets.
- Since there is no combustion process and the brine circuit is closed, a brine-to-water heat pump is particularly reliable.
Prerequisites for a brine/water heat pump
The most important prerequisite for a brine/water heat pump is the condition of the ground and the available area.
The suitability of the soil must be professionally tested and a permit obtained. Depending on whether a ground probe system or ground collectors are to be used, sufficient space is required on the property. While a wide area is required for the installation of ground probes, ground collectors are drilled into the depth of the property.
Geothermal energy as an energy supplier
Earth is so much more than just soil under your feet. Soil is the habitat of many animal inhabitants and the basis of our nature. From it we extract the heat for our brine-to-water heat pumps to heat and cool buildings in a climate-friendly way and to supply them with domestic hot water. The great advantage of the ground as a heat supplier is its constant temperature: In summer and winter, the temperature in the ground is around 8 - 10 degrees Celsius.
WHAT IS GEOTHERMAL HEAT?
Energy is stored in the ground through solar radiation or precipitation. The temperature in the ground is constant all year round, around 8-10 °C depending on the region. The heat pump uses this stored energy to generate heat.