TÜV Rheinland (Technical Inspection Association) is enhancing the comfort of 2,500 users at its Cologne headquarters. An energy control concept developed by Drees & Sommer – together with the energy-efficiency upgrade – paves the way for the future of the buildings and increases the overall economy. The achieved value-add includes a significant reduction in energy and operating costs through the high-efficiency standard, a cut in primary energy demand of about a third, and a similar reduction in the carbon footprint.