Synthesis of numerical Model Approaches for Reservoir Treatments in Enhanced Geothermal Systems | SMART-EGS
Thermo-Hydraulic-Mechanical (THM) coupled processes play a central role in various geological and geotechnical issues, including in the field of nuclear waste disposal, slope stability analysis, underground storage, and hydro- and petrothermal geothermal energy. In particular, fracture formation processes, i.e., the dynamic development of discontinuities in rock that can act as hydraulic pathways, place extremely high demands on numerical concepts. SMART-EGS aims to contribute to the development of a robust workflow for such problems, based on two fundamental concepts: a scaling-up approach and the parallel comparative use of three different numerical concepts. The simulations are based on real measured data, with which the models are first calibrated and then validated. The implementation of the workflow ultimately aims at predictions for the development of a multi-fracture system for the petrothermal utilization of the subsurface. The data basis for SMART-EGS comes from the mini-frac experiments in the Bedretto Underground Laboratory, the additional experimental investigations planned there, and the field-scale Deep Heat Project by ST1 in Finland. As a result of the method development, concepts for at least one real pilot site for petrothermal utilization of the subsurface will be developed.
- Development of a Robust Workflow: Create a unified workflow for THM-coupled simulations of fracture propagation and reservoir optimization in EGS projects. Compare and contrast three different numerical modeling techniques (continuum, discrete element, and particle-based methods) to identify their strengths and weaknesses for various stages of EGS development.
- Model Validation and Verification: Validate the models using experiment data from the Bedretto Underground Laboratory (pilot scale) and the ST1 Deep Heat Project (field scale). Ensure the reliability and accuracy of the models for predicting fracture behavior and reservoir performance.
- Optimization of EGS Systems: Optimize the design and operation of multi-fracture systems for geothermal energy extraction, focusing on improving flow rates and thermal recovery. Conduct risk analyses to minimize induced seismicity and other potential hazards associated with EGS operations.
- Application to Field Projects: Apply the developed workflow to a pilot project for urban heat supply, demonstrating the feasibility of using EGS for district heating and heat storage.
- G.E.O.S. Ingenieurgesellschaft mbH (GEOS): Project coordination, continuum modeling, and risk analysis.
- TU Bergakademie Freiberg (TUF): Discrete element modeling and fracture network simulations.
- Helmholtz Centre Potsdam – GFZ German Research Centre for Geosciences (GFZ): Particle-based modeling and reservoir engineering.
- Ruhr-Universität Bochum (RUB): Experimental data acquisition and analysis from the Bedretto Underground Laboratory.
