The drilling phase of the geothermal heating project in Olching-Geiselbullach in Germany has been completed, with well testing results indicating positive findings. Work has now started on installing the pumps and constructing the district heating station, and commercial heat supply is expected to start no later than the 2027 heating season.
On August 2026, the performance tests of the second well were completed, about six months after drilling work officially started. The well discharged thermal waters at 79 to 80 ºC, at a flowrate of 90 L/s. Based on these performance data, the well can produce about 10 MW of geothermal heat output – as was the target during the project’s planning phase.
The geothermal project is headed by Amperland Thermalwärme GmbH (ATW), a subsidiary of Joint Municipal Company for Waste Management (Gemeinsames Unternehmen für Abfallwirtschaft / GfA), the company that currently operates the waste-to-energy plant in Olching-Geiselbullach.
First announced in 2023, the project aims to provide an alternative source for the existing district heating network. For decades, the energy from waste incineration had been used to produce electricity and district heating. Shifting to geothermal energy is considered a vital building block to an overall heat transition.
Based on the well parameters, the geothermal resource can provide a portion of the heat previously supplied by the waste incineration plant. The additional capacity will also allow for further expansion of the regional district heating network. As an additional heat source, geothermal energy also increases the flexibility and security of supply of the overall system.
The progress of Geiselbullach is an example of how geothermal heat can be economically integrated into an existing supply system by taking advantage of existing infrastructure and heat generation facilities. After less than five years since the start of initial planning, the project is now progressing to the next crucial phase.
Source: Amperland Thermalwärme
