The DLR site in Jülich is located about 60 kilometres west of Cologne and, since mid-2011, has been home to a working group of the Institute for Solar Research. On 1 July 2011, DLR acquired the Solar Thermal Test and Demonstration Power Plant Jülich (STJ) from Stadtwerke Jülich GmbH (Jülich Public Utility Company).
As a dependable technology, solar thermal power stations can play an important role in transitioning the power grid to renewable energy sources. In contrast to other renewable sources, they supply electricity on demand and can stabilise the grid.