Groundwater

The most efficient heat pumps are operated with groundwater. This is a result of the fact that the annual average groundwater temperature is between 8° and 12° C. The warmer the heat source, the more efficient the heat pump can operate. Two well bores are required in order to use groundwater: one withdrawal well and one injection hole.

The investment costs are low compared to other heat sources and also do not increase at greater heating output. Approval is required from the federal state government (water protection area). The groundwater needs to be analysed in terms of its suitability for use in heat pumps. The required volumetric flow of groundwater depends on the required heating output and is detailed in the technical data sheet.

Geothermal Probe / Vertical Collector

The geothermal probe is an enclosed system in which brine (mixture of water and antifreeze agent) circulates. Depending on the heat requirements, the probes are sunk up to several hundred metres vertically into the ground. It is particularly important here that the probes are not designed too short. The investment costs for special drilling(s) are higher than for other heat sources. The higher the heating output, the higher the investment costs. If the heating output is doubled then the investments are also doubled.

Surface Collector / Horizontal Collector

In the case of a surface collector, PE pipes are sunk horizontally at a depth of around 1.5 metres (underneath the frost zone) in the garden. Brine (mixture of water and antifreeze agent) circulates in this enclosed system. The higher the heating output, the higher the investment costs. If the heating output is doubled then the investments are also doubled.