The actual paradigm for energy production is centralized and based on large power plants with a top to bottom configuration. The new challenge is to abandon as soon as possible fossil fuel power plants and to use more renewable energy resources, supporting small power plants where energy sharing and self-consumption are the main milestones. In order to achieve this transition, the best solution is to encourage the spread of Renewable Energy Communities. This thesis aims to develop an Energy Information System focused on the simulation of the community itself in order to facilitate the evaluation of a potential investment and to make conscious decision.