We conducted a computer-aided socio-technical analysis on national and regional energy systems. Existing developed models were simultaneously utilized for characterizing the possible solutions of energy systems with the available technology roadmaps. At the same time, we analysed consumers’ preferences about the electricity supply through preference surveys in whole Japan and a remote island Tanegashima. As socio-technical analysis, the basic information on the performance and behaviour of energy systems and consumers’ preferences were interpreted based on the results of energy-system simulation and willingness to pay calculated by the survey results. The solutions for the design of national and regional energy systems were generated through the consideration of local availability of renewable resources.