The sustainability of the European Regions, in terms of society and economy and environment, is strongly based on renewable energy and resource efficiency. This implies the large scale deployment of nearly Zero - Energy Buildings (nZEBs). As well as the technology is already available and proven. However the diffusion of nZEB in Mediterranean areas is a challenge for the local market actors considering the short time. In this direction our research is oriented, proposing the case study of the first passive building in Putignano (Apulia). The goal is to observe the impact of the comfort setting on energy demand during the everyday life. This new approach aims at simultaneously considering both the energy performance and the comfort and health of the inhabitants. The case study includes the simulation model and the measuring campaign. It aims to verify if occupants of nZEB will be aware of the qualities of their home and learn to manage and monitor energy consumption independently. The concept is to observe the impact of comfort setting on energy demand during the everyday life in heating season of the passivhaus tenants.