The energy transition requires a heat transition, especially in urban centres where heat demand is high, and space is limited. Deep geothermal is one of the few “green” alternatives to fossil fuels that can provide base load heat, chill, and electricity. In Germany, 25% of the heat demand could be supplied by conventional hydrothermal systems, but the hydrothermal potential is not available everywhere and the petrothermal energy potential is orders of magnitude higher.

In our research group, we develop and demonstrate methods for improving the performance of deep geothermal reservoirs with insufficient permeability (petrothermal energy) while minimizing environmental impacts such as induced seismicity (“soft stimulation treatments”). Our results will thus reduce risks, improve economics and accelerate geothermal energy development by a better understanding of the governing processes and enabling the development of previously inaccessible resources. Research methods include experiments at the laboratory, mine and field scales as well as numerical and analytical modelling. We pursue our research in tight interdisciplinary collaboration across scales and across disciplines together with national and international partners.

The two PhD students will support the work of the group by working on one of the following topics with the help of laboratory injection experiments and numerical modelling:

1)   adaptive fluid injection for improved hydraulic stimulation control

2)   systematic analysis of the influence of operational and geological factors on induced seismicity and permeability enhancement

3)   development and investigation of new Enhanced Geothermal System development concepts

Laboratory experiments include hydraulic fracturing and hydro-shearing experiments and numerical modelling studies range from grain-based modelling of laboratory experiments to field scale models of EGS sites. The specific tasks will be determined based on the interests and capabilities of the individual applicants.

The results will improve the physical understanding of hydraulic stimulation treatments and associated fracture development, permeability increase and injection-induced seismicity. This will support the improvement of reservoir stimulation concepts to develop Enhanced Geothermal Systems (EGS) in a safe and economic manner.

We are looking for highly motivated, creative and target-oriented candidates that want to do research with a purpose. As a team, we will support you in starting a fulfilling career in the field of deep geothermal energy development in science or industry, depending on your personal preferences.

Your responsibilities:

• Use, validate and possibly improve existing numerical codes and develop tailor-made modelling workflows to study hydraulic fracturing, shear stimulation and the induced seismicity and hydraulic performance increase in geothermal reservoirs at multiple scales
• Perform and analyse hydraulic fracturing and/or hydraulic shearing laboratory experiments to investigate the physical processes dominating the mechanical, seismic and hydraulic response of geothermal reservoirs to different hydraulic stimulation treatments
• Improve the physical understanding by upscaling and downscaling
• Publish in international peer-reviewed journals and present results at scientific meetings
• Co-supervise BSc and MSc students

Your qualifications:

• MSc degree (or equivalent) in reservoir/petroleum engineering, applied geosciences, environmental sciences, geophysics, geology, physics, mathematics or equivalent
• Proficiency in spoken and written English; German language skills are useful, but no strict requirement
• High motivation and creativity as well as a result-oriented, structured and reliable working attitude
• Willingness and ability to work in diverse, interdisciplinary and international teams
• Excellent communication skills
• Background knowledge and experience in the topics of geothermal energy, rock mechanics, seismology or hydraulic fracturing and programming, numerical methods, analytical methods or laboratory methods are useful, but no strict requirement