As part of the SKEWS research project, three 750 m deep boreholes with an average center distance of 5 m were drilled at the Lichtwiese campus of Darmstadt Technical University. Completion will take place in December 2022, when the boreholes will be upgraded to medium-depth borehole heat exchangers with a coaxial pipe arrangement. The three borehole heat exchangers will then be operated in a 1.5-year research operation as the world's first medium-depth borehole heat exchanger. The project will demonstrate the constructability and operability of such systems and determine the operating and design routines for future projects.