This thesis presents the development of an interactive data visualization platform designed to support decision-making within Renewable Energy Communities (RECs). As societies transition away from fossil fuels, RECs are emerging as key players in promoting local, decentralized energy systems—particularly through the use of solar energy. However, effective planning and management in these communities require transparent, accessible, and comprehensible data tools. To address this need, the research adopts a methodology that combines Geographic Information Systems (GIS), Business Intelligence (BI) tools, and stakeholder analysis. The platform is tailored to the needs of diverse actors, including local authorities, citizens, utilities, and investors. A comprehensive review of stakeholder requirements informs the selection of key indicators—such as self-consumption, self-sufficiency, and economic savings—ensuring the platform supports both technical and participatory decision-making.