The course aims to provide the knowledge necessary to carry out the analysis of the energy performance of buildings, taking into account the following energy services: winter heating, summer cooling, domestic hot water production, ventilation, lighting, other electrical uses. For this purpose, the course treats the fundamental aspects related to the evaluation of the useful energy demands of each considered service and the efficiency of the systems dedicated to their satisfaction. The performance indicators, widely used in Europe for the energy certification of buildings, are also defined.