A graphic tool for process system analysis and/or synthesis based on the second law of thermodynamic is developed. When a simple program to describe the system is given, the compiler GSCHEMER, Graphic Structured CHEMo-synthesizER, will analyze it and display the energy utilization diagrams, clarifying the extent of exergy loss in each part of the system. This method covers operations of chemical reaction, heat exchange and gas compression and expansion. In addition, these diagrams may reveal the causes of exergy loss in each subsystem and give some hint as to how it may be reduced. This systematic visual procedure may be applied not only for process system analysis and evaluation but also for synthesis of new systems to save energy. In this paper, a sample program for coal gasification is given. Scope—To efforts to get efficient energy transformation in chemical or energy process systems may be classified into two stages: analysis (or evaluation) and synthesis. In previous methods for energy analysis, the object processes were often treated as black boxes and only the energy efficiency in them was evaluated by the thermodynamic properties of the flows at their inlets and outlets. Such methods have been applied for a long time but they are generally insufficient to obtain information on how the system may be improved. With respect to the synthesis of process system networks or the optimization of the system structure and operation variables, many mathematical methods have been proposed. Among them, graphic methods for heat-exchange networks such as the heat-content diagram by Nishida et al. [1], the heat-temperature diagram by Hohman [2], the heat-available energy diagram by Umeda et al.. [3] and their applications [4] are the most successful, because graphic methods are best-suited to inspire human intuition. However, most of them are not beyond the scope of heat-exchange operations. Hence graphic methods which may be applied to any kind of process system may become candidates for the method of energy analysis and system synthesis in the next generation. In a previous paper [5], one of the authors has proposed the energy-direction factor diagram. Although it has characteristics similar to Umeda et al.'s diagram [3] for heat-exchange operations, in the sense that the exergy loss in the network can be represented as the area between the heat-donating line and the heat-accepting one, it has much wider applications-including chemical reaction, gas compression and work generation. In another paper, Ishida has proposed a compiler-type steady-state process system simulator SCHEMER, Structured CHEMo-synthesizER [6], in which the introduction of the concept of “stream stack” makes the simulator quite compact. The purpose of this study is to combine the advantages of these two efforts and develop a new graphic simulator GSCHEMER. It will display energy-utilization diagrams which may become a powerful tool in energy analysis and process system synthesis. Conclusions and Significance—(1) A graphic simulator, GSCHEMER, for steady-state process systems is developed. (2) Energy-utilization diagrams, which are an extended version of the energy-direction factor diagrams, are automatically generated for each subsystem such as heat-exchange operation, work task and chemical reaction. (3) Each diagram shows the energy balance, the extent of exergy loss and the extent of the approach to equilibrium, especially at the pinch point in each subsystem, which are of great importance in finding the causes of irreversibilities and in proposing a new system structure.