Current data about energy characteristics at the community level are representing an important baseline for the development of strategies for efficient energy use in these communities. This work is an integral part of the Interreg IVA project "AlterVis - Self-sufficiency through renewable energy sources" with the goal to capture the renewable energy potential in the district of Hermagor in Carinthia, Austria. Therefore, a WebGIS portal for capturing, managing, analyzing, and visualizing energy characteristics based on open source technologies has been implemented. The focus of this work deals with the development of a uniform and global system which allows citizens to participate in a standardized survey regarding the energy consumption of their household/building(s). The survey results can be visualized in the forms of tables, diagrams and maps, which provide more detailed information about the current energy consumption of the household and each building. After the user has completed the survey the portal provides the user's personal energy data as benchmark with Austrian-wide statistics of "Statistik Austria" for the three main categories electricity, building heat, and mobility. This "bottom-up" allows the efficient comparison between planning units and provides the basis for extending and implementing this project for all communities in Carinthia.