The new concept of renewable energy communities introduced by the Revised European Directive on the promotion of renewable sources (2018/2001) has opened new possibilities for microgrids. In fact, it permits to enhance the value of the energy produced by renewable sources sharing it inside an “energy community” and to increase the social welfare. In this article, the authors investigated about the actual legislation framework on energy communities at the European and Italian level, highlighting regulatory problems and barriers that are delaying their constitutions. The authors propose a “power sharing model” (PSM), which is useful for energy communities based on the sharing of renewables and other energy services. The PSM is suitable for both the building level and larger communities. PSM has been analyzed through a case study that regards the preliminary study of a smart microgrid that should be realized in Campobasso, Italy, to connect buildings of the public administration. This scenario was investigated through a simulation conducted in Simulink environment where the control strategy was implemented, and the results were compared to a traditional configuration for renewable sources integration. The results highlight the adequacy of PSM for the energy community for the building's microgrids application.