We had to know the annual number of meals prepared here. According to a Swiss study [11], there are 2.3-3.1 kWh required to cook a hot meal in a canteen kitchen. However, Rohatsch [12] published val- ues ranging from 0.7 to 0.8 kWh/meal. The detailed analysis of a Luxembourg school verified the performance of installed kitchen equipment and the average operating times. As a result, a mean