In November 2006, the overall concept for the modernization of the refectory of the Mainz student union earned the Energy-Plus Quality Seal. The seal is awarded by the Environment Ministry of the federal state of Rhineland-Palatinate for outstanding ideas and concepts in technical building services, heat insulation, energy generation and utilization, and manufacturing.

Within a closed energy performance contract concluded in 2005, HOCHTIEF Energy Management carried out the modernization works in the refectory without disrupting normal operations. The measures implemented by HOCHTIEF produce savings of EUR 260,000 a year on energy costs for the student union. This represents a 50-percent reduction of the previous energy consumption. In addition, the emission of CO₂ has been cut by around 45 percent.

The measures implemented by HOCHTIEF include the installation of a steam generating facility for cooking and dish-washing and modern building systems instrumentation and control technology, and the retro-fitting of heat recovery systems. Modernization and optimization measures have also been carried out in the fields of ventilation, heating, refrigeration, water and lighting.