Fraunhofer Research Institution for Energy Infrastructures and Geothermal Systems IEGOur laboratories, test beds and observatories at the locations in Bochum Cottbus, Weisweiler and Zittau form the experimental backbone of our research activities on the transformation of energy systems. As a significant part of the processes related to the provision and use of geogenic resources takes place at depths that only allow indirect measurement methods, we operate an infrastructure that enables observation of these processes across different spatial and temporal scales. Processes and parameters on the micro-scale (micrometre-decimetre) are observed in our Geoscience Laboratory. The mesoscale (decimetre-metre) is the focus of our Geotechnology Laboratory. The macro scale (metre-100s of metres) is investigated with the help of our drilling operations. In order to investigate the integration of various renewable energy resources into as well as the potential of sector coupling technologies for the future energy mix, we are building various test rigs in our energy technology laboratory. To demonstrate all technology lines, we are currently developing two field scale laboratories that will enable the transfer from science to application.