The design of energy systems has become an issue all over the world.A single optimal system cannot be suggested because the availability of infrastructure and resources and the acceptability of the system should be discussed locally,involving all related stakeholders in the energy system.In particular,researchers and engineers of technologies related to energy systems should be able to perform the forecasting and roadmapping of future energy systems and indicate quantitative results of scenario analyses.A computer-aided analysis is strongly needed for such purpose.