Graben-Neudorf, Germany geothermal project on track for second drilling in 2026
Rig operations at Graben-Neudorf geothermal project site, Germany (source: Deutsche Erdwarme)
Carlo Cariaga
11 Aug 2025
Preparations are underway for the drilling of a second well in the Graben-Neudorf geothermal project in Germany, at the site of a previously drilled 200 °C well.
The geothermal project of Deutsche ErdWärme in Graben-Neudorf in Baden-Württemberg, Germany is progressing according to plan, with preparations ongoing for the drilling of a second well in 2026.
Drilling of the first geothermal well in Graben-Neudorf started in 2022. Thermal waters at 200 °C were found at a depth of 4000 meters, making it the hottest geothermal well in Germany at this depth. Injections tests done in 2024 also indicated that the injectivity of the well was better than initially expected.
To better understand the potential of the geothermal resource, Deutsche ErdWärme applied for a second injection phase to the Freiburg Mining Authority. Following successful approval, an injection test lasting several weeks is planned for the fourth quarter of 2025. The goal is to validate the reservoir’s sustainable injection capacity and to operationally test operating procedures under real-world conditions.
In parallel with the preparations for the injection phase, the second well is already being planned and is scheduled to be drilled soon. All previous findings will be incorporated into the technical and geological planning to advance the project and thus the local heat transition. “A second drilling cellar is already in place for the well, and planning for the heating plant is well underway,” said Rolf Herrmann, Head of Geothermal Engineering for Deutsche Erdwärme.
The final use of the geothermal plant—as a combined heat and power plant (CHP) or as a pure heating plant—depends on further tests and infrastructure planning. The planned heat supply for the Bruchsal, Dettenheim, and Bretten region plays a particularly central role in this.
A step forward in the heat transition
State Secretary Dr. Andre Baumann from the Ministry for the Environment, Climate Protection, and Energy recently visited the drilling site in Graben-Neudorf. During the visit, Deutsche ErdWärme presented the next steps in the project’s progress as well as the visualization of the subsurface using 3D modeling and simulation software to better convey geological relationships.
The presentation of the 3D geothermal model was a central part of the visit, as this making it possible to visualize the complexity of the subsurface and allow for a new level of transparency for geothermal projects. “With 3D visualization, we create a better understanding of the geological conditions of geothermal projects and can better involve stakeholders without geological expertise,” explained Herrmann.
“Geothermal projects like the one in Graben-Neudorf are a good example of bold progress in the heat transition. They unearth a treasure and help ensure a sustainable and independent energy supply. This will enable us to significantly reduce our dependence on fossil fuels while simultaneously advancing our climate goals,” said Dr. Baumann in support of the project.
Source: Deutsche Erdwärme and BNN
