GeoTWIN: Deep Geothermal Energy for Heat Supply in Northern Germany

01.01.2021 - 30.06.2022

Dr.-Ing. Michael Koppe (DSC - TU Clausthal)
Prof. Dr. Philip Jaeger (ITE - TU Clausthal)
Prof. Dr. Leonhard Ganzer (ITE - TU Clausthal)

The expansion of renewable energies is at the heart of the energy transition. So far, limited success has been achieved with deep geothermal projects. A central role for success is played by location and reservoir selection as well as the application of the right development and utilisation concepts and technologies. The latter are crucial for a safe, optimised and economic development of these projects.  

The focus of the project is to explore the recoverability and storability of geothermal energy from depths of up to 1,700 metres at a specific location in the North German Basin with high salinity and high gas loading in subsurface waters. The aim is to examine whether the ability to extract and store geothermal energy also makes technological sense in terms of costs. To this end, a scientifically validated concept for hydrothermal heat extraction and seasonal heat storage is to be developed in the Hannover/Burgwedel area. The Clausthal University of Technology has a mining licence for geothermal energy.  

Sub-objectives of the project are:

• Analysis and interpretation of existing extensive data (seismics, drilling reports, borehole data and measurements, production data) as well as their integration into a uniform database (3D  reservoir model)
• Subsurface characterisation, modelling and numerical simulation of scenarios for heat extraction and storage (borehole type, borehole spacing, temperature development)
• Modelling of the water cycle to avoid salt precipitation, gas dissolution and solution processes
• Simulation of drilling process and borehole stability
• Presentation of a concept as well as a planning for the well construction (borehole course, mud and cementation programme and casing design)
• Presentation of a concept for the completion of stratified aquifers in sandstones
• Presentation of a concept for the process engineering facilities for the treatment of the thermal waters produced and to be re-injected
• Evaluation of alternative production aids
• Risk analyses and economic evaluation on a cost basis