In response to the growing interest in environmentally friendly energy-efficient transportation systems, Mitsubishi Heavy Industries, Ltd. (MHI) has developed a simulation system for evaluating the operational aspects and energy efficiency of guided transportation systems. The simulator can be used to analyze not only conventional systems that use a contact line to supply electricity to trains, but also energy-smart transportation systems that use a battery. Improvements in system design efficiency and optimal system planning are now possible because the simulator enables the comprehensive evaluation and energy analysis of complete transportation systems as well as single trains. This article provides an overview of the simulator.