ADVANCED EXERGY-BASED ANALYSES APPLIED TO SUPERCRITICAL CO2 POWER CYCLES

The idea of developing supercritical CO2 power cycles and applying them to industrial processes became increasingly popular in the last decade. Significant research has been done in this field, including the investigation of characteristics of equipment, and parametric optimization of power systems. There are only few publications on refrigeration using CO2 under hot climatic conditions. This paper deals with an application of an integrated conventional and advanced exergetic analysis to a supercritical CO2 power cycle operating in hot climatic conditions. The objective is to obtain detailed useful information about the optimization of the structure and the parameters of the system being considered. Conventional exergetic analyses have some limitations, which are significantly reduced by the so-called advanced analyses. In addition to conventional analyses, the latter evaluate, (a) the interactions among components of the overall system, and (b) the real potential for improving a system component A conventional exergetic analysis emphasizes more the relative importance of the regenerative heat exchanger compared to the remaining four components (compressor, cooler, expander, and heat exchanger) than the advanced analysis does. The results obtained from the advanced exergetic analysis show that the system being analyzed can be improved by improving the components in isolation from the overall system, because the avoidable inefficiencies caused by the components interconnections are relatively low.