Oct 2023
Sustainable and efficient use of the geothermal resource sitting below the city of Munich (Germany) is a topical issue for the local energy providers. Indeed, by 2035, Munich city expects to supply 100 % of its electricity and heat demand from renewable energies. Hence, the exploitation of the highly conductive aquifer, the Malm formation, will be intensified with the development of numerous new geothermal power plants. This is a challenging task, which requires better understanding of the coupled processes taking place underground and of their effects, especially in terms of possible induced seismicity and ground uplift or subsidence. These last two concerns are at the heart of the INSIDE research project.
This seminar will discuss key components of the INSIDE project, which focuses on two geothermal sites located south of Munich city. At first, the passive seismic monitoring network implemented will be presented. Its peculiarity lies in the combination of several tool types and network designs to assess their advantages and disadvantages in an urban area. This includes the use of surface sensors, borehole sensors, a mini-array, and Distributed Acoustic Sensing (DAS) utilizing fiber optic cable (FOC). Monitoring results will be showcased, with a particular focus on those obtained through the DAS technology after appropriate data processing. Another aspect will describe the pseudo-real time integration of the DAS data in the IT infrastructure of the field operator to prepare real-time seismic processing and later assimilation of the results into a “Reservoir Management System”. Besides seismic monitoring, numerical reservoir modelling constitutes another pillar of the project. Specifically, thermo-hydro-mechanical (THM) modeling of the long-term exploitation of one of the deep geothermal sites was conducted. The response of the reservoir to potential additional wells for enhanced power recovery was investigated and a comparison with the original scenario was made.
References:
Azzola, J. & Gaucher, E., 2023. Continuous seismic monitoring of a geothermal project using Distributed Acoustic Sensing (DAS): a case study in the German Molasse Basin, Presented at the EGU Conference 2023.
Egert, R., Gaucher, E., Savvatis, A., Goblirsch, P. & Kohl, T., 2022. Numerical determination of long-term alterations of THM characteristics of a Malm geothermal reservoir during continuous exploitation, Presented at the European Geothermal Congress 2022.
Gaucher, E. & Egert, R., 2023. Change of the THM properties of a Malm geothermal reservoir under present and future exploitation schemes, Presented at the EGU Conference 2023.
Gaucher, E., Hansinger, M., Goblirsch, P., Azzola, J. & Thiemann, K., 2022. Towards a geothermal reservoir management system, Presented at the European Geothermal Congress 2022.
Dr. Emmanuel Gaucher is a geophysicist whose interest concentrates, for more than 25 years, on the seismicity induced or triggered by geo-reservoir exploitation (e.g. oil and gas, deep geothermal), its link with the well operations and the geological/geophysical context. He is focusing on the underlying processes at the origin of the induced seismicity, their modelling and the consistency with the observations. Current research projects apply on the Upper Rhine Graben and on the German Molasse basin. They include acquisition and processing of induced seismicity for deep geothermal field characterization, thermo-hydro-mechanical modelling of geothermal reservoirs and integration of both aspects by the field operator for sustainable reservoir management. Emmanuel is also investigating the potential of Distributed Acoustic Sensing for seismic monitoring as well as the coupling of seismicity occurrence with THM reservoir models.
After finishing his Ph.D. in geophysics at the Institut de Physique du Globe de Paris in 1998, Emmanuel spent 12 years working for service companies in the oil and gas sector for hydrofrac passive seismic monitoring (CGG-Veritas and Magnitude-Baker-Hughes). Among other things, he carried out research and developments in the above-mentioned topic and led several projects for international operating companies (e.g. BP, PDO, Saudi Aramco, Kuwait Oil Company, Total). In 2010, he joined the department of Geothermal Energy and Reservoir Technology of the Karlsruhe Institute of Technology. Besides his lecturing duties (induced seismicity, borehole logging, scientific computing and reservoir modelling), he is/has been involved or led several national or international projects associated with seismicity induced in deep geothermal fields. He also acts as scientific advisor on the seismic monitoring at several geothermal fields under development.