The Geothermal Research Platform Groß Schönebeck offers in situ test facilities using two wells in Groß Schönebeck which reach to a depth of nearly 4.3 km (~150 °C) to support the development of system components for a reliable use of Geothermal Energy. The operation of a thermal water loop provides temperature, pressure, phase behavior and salinity of the circulated natural fluids under extreme hostile test conditions. Here, key system components are incorporated, continuously tested under different operational conditions, and subsequently improved. So, a unique research and technology infrastructure is established to qualify materials and system components for sustainable long-term operation of Enhanced Geothermal Systems.