Sebastian Geiger
Since March 1, 2022, Prof. Dr. Sebastian Geiger (1974) has been a full-time professor of Sustainable GeoEnergy at the Faculty of Civil Engineering and Geosciences. Since June 2025, he has also been chair of the Geoscience & Engineering department. Previously, he spent 16 years at Heriot-Watt University in Edinburgh (Scotland) where he served as Director of the Institute of Geoenergy Engineering. He led the transition from a successful but traditional engineering institute to one with a mission to accelerate the energy transition. He also served as Director of Research at the School of Energy, Geosciences, Infrastructure and Society.
His groundbreaking research and techniques have received significant acknowledgement, including the Alfred Wegener Award from EAGE in 2017 (European Association of Geoscientists and Engineers). Additionally, in 2020 and 2022 he was awarded the Fellowship from respectively the Royal Society of Edinburgh and the Royal Academy of Engineering of the United Kingdom. The RRM software, co-developed by Geiger, has also gained wide recognition in the industry. After his position in Delft, this formed the basis for successful fundraising Dutch Research Council and the European Commission.
Sebastian Geiger came to TU Delft to develop and lead the Geoscience Twin for SubSurface Energy Lab. This GETSS Energy Lab is part of the Energi Simulation Centre for Geoenergy.
Developing a digital twin
The ambition of the GETSS Energy Lab is to develop a modular and open source 'digital twin' for underground energy systems. This digital twin will combine scarce data from one-time measurements with data from (semi)continuous monitoring, process models and AI approaches. This will make visible the condition of the subsurface, as well as the physical-chemical interactions with energy-carrying fluids and gases. This helps us develop more secure and more sustainable of subsurface resource for the energy transition. Thus, this digital twin can become a cornerstone for larger digital twins exploring the energy systems of the future. The Delft Geothermal Project for geothermal heating research, will be the first to apply this digital twin.
Rapid Reservoir Modelling as a foundation
The development of the digital twin utilises the results of RRM software (Rapid Reservoir Modelling). This innovative software for underground energy modelling has been developed for over 8 years in collaboration with Imperial College London and the University of Calgary. It is called 'rapid' because it reduces the time for identifying and characterising underground reservoirs from 6-12 months to 4-6 weeks.
Energy transition and energy justice
One of the United Nations's 17 Sustainable Development Goals for 2030 is 'access to safe, affordable, and reliable energy for all.' There is thus a direct relationship between human development and access to energy. Currently, there is energy injustice. Around 3 billion people in the world experiemce acute energy poverty, while developed countries are responsible for 90 percent of harmful CO₂ emissions. Current energy research focuses on developing sustainable forms of energy, but the UN goal of 2030 and the goals for zero CO2 emissions still seem distant. By integrating geosciences and reservoir engineering techniques, we can make faster progress in reducing CO₂ emissions and achieving a just energy transition. On the one hand, by capturing and storing CO₂ emissions (CCS) in deeper geological formations. On the other hand, by using geothermal heat (like in the Delft Geothermal Project) for district heating. Nearly 50% of the total energy that we consume in the global north is for heating purposes. In the EU alone it is estimated that geothermal energy can lead to a 15 percent reduction in CO₂ emissions.
Geiger himself expresses his main drive and impact as follows: 'Educating a new generation of engineers with a holistic view of the energy transition, who are part of a rapidly growing, global network.'
Educating a new generation of engineers
Geiger and Prof. Hadi Hajibeygi are jointly building TU Delft's Energi Simulation Centre for Geoenergy, which aims to be an ambitious research centre. In 2025, the Canadian NGO Energi Simulation has committed to providing funding for another five years. This means 20 years of non-stop funding for research and the training of MSc students, PhD students and postdoctoral researchers. The goal for the next five years is to train 35 engineers. For MSc students, Geiger, together with others, has developed a new curriculum on the applications of geoenergy. This includes innovative, interactive workshops and scenario planning exercises to investigate the real problems that society will face in the transition to a sustainable future. In addition, Geiger is also publicly committed to preserving earth science programmes at other universities.
Building a global network
The Delft Energi Simulation Chair is part of a worldwide network of Energi Simulation Chairs, with whom close collaboration is maintained. The collaborative relationship continues also with the Heriot-Watt University, most visible through the PETRONAS Centre of Excellence in Subsurface Engineering and Energy Transition (PACESET). These partnerships are constantly expanding. For example, Geiger is leading an EU project to develop faster exploration methods for geothermal energy (in collaboration with ETH Zurich, Imperial College London, University of Cologne, Charles University of Prague and industry partners from Spain, France, Czech Republic, UK and Iceland). A new project, funded by the Dutch Research Council under the DeepNL programme, should help improve the forecasting of geoenergy reservoirs, and in a number of smaller projects, Geiger is working with industry partners on several aspects of CO2 reduction and storage. In collaboration with the Norwegian SINTEF - one of Europe's largest independent research institutes - the Matlab Reservoir Simulation Toolbox is developed. This is an open source toolbox for geoenergy solutions, with over 1,000 unique downloads per year. Furthermore, Geiger is also co-founder and editor-in-chief of the magazine Geoenergy.
For clean energy
The societal impact of Geiger's research (a clean and just energy transition by reducing CO₂ emissions) seems easily translatable into supporting funding from grants and by industries. In addition to Geiger's scientific work, which is reflected in scientific publications (see here), the development of the RRM software is of great societal value. New releases of this software and others are regularly released as open source for industry and science, most recently in 2025.
Geiger's Personal Passion Pride
'The fact that I cannot 'see' my research object makes it all the more intriguing. Nothing is certain, yet I try to make something concrete out of the unseen. Papers are nice, but creating something that has real impact, that makes people think and look in new ways - that means much more to me. That is my drive to make my research valuable for real life.'
'TU Delft is a leader in energy transition'
Sebastian Geiger's chair is co-financed by Energi Simulation, a non-profit organization from Canada (Calgary), which supports research activities in geosciences and reservoir engineering. With the investment from the Excellence Fund, Geiger is enabled to develop a modular and open source 'digital twin' for underground energy systems. For this purpose, the Delft Energi Simulation Centre for Geoenergy closely collaborates with other Energi Simulation Chairs. 'But', says Geiger about this, 'TU Delft is the frontrunner in Europe and one of the leaders in energy transition globally. Our holistic, integrated, and collaborative approach to it is unique. With a crucial role for geoscience, reservoir engineering, and multi-scale modelling. And with unique research facilities, such as the Delft Geothermal Project.’
@GeoenergyProf en YouTube
The 'GeoenergyProf,' as Geiger is called on X, has over 1,200 global followers there. With passion, he promotes his science to anyone who wants to follow him. A few years ago, during the pandemic, he developed the Geoscience and Geoenergy YouTube channel together with TU Delft professor Hadi Hajibeygi. At that time, a new episode was released every Thursday at 4:00 PM; at this point, there are 120 episodes. Almost 3,800 subscribers from all over the world follow these webinars, which together have already amassed over 133,000 views!