From the viewpoint of the cascading utilization of thermal energy, we focused on power recovery by Rankine cycle driven by exhaust gas coming from the micro-gas turbine. Removing chlorine atomic from conventional fluorocarbons, named by CFC and HCFC, brings higher temperature of the expander inlet up to about 200 degree-C, so the higher performance of Rankine cycle is expected. In this study, we have discussed the working fluids for Rankine cycle, the performance of main elements such as refrigerant pump and evaporator, and the performance of cycle. Experimental data analysis shows (1) The efficiency of scroll type expander is about 60%, (2) Cycle efficiency with regenerator is half as much again as that without regenerator, and (3) Maximum of cycle efficiency is about 9%.
