With the help of circulation fans, an improvement in convective heat transfer in tunnel kilns can be achieved relatively easily. Thanks to the higher heat transfer, a considerable amount of fossil energy can be saved. For this, however, electric energy is needed additionally for the fans. The total primary energy consumed must therefore be minimized. In the scope of a joint research project of the Brick and Tile Research Institute and the Institute of Fluid Dynamics and Thermodynamics at the University of Magdeburg a concept is being developed that should allow the relatively simple conversion...