Performance analysis of solar driven combined recompression main compressor intercooling supercritical CO_(2) cycle and organic Rankine cycle using low GWP fluids

Current study deals with performance evaluation of the solar power tower driven recompression with main com-pressor intercooling(RMCIC)supercritical CO_(2)cycle incorporating the parallel double evaporator organic Rank-ine cycle(PDORC)as bottoming cycle using low global warming potential fluids to reduce the global warming and ozone depletion.Using the PDORC instead of the basic organic Rankine cycle,waste heat from the intercooler and cycle exhaust were recovered simultaneously to enhance performance of the standalone RMCIC cycle.Exergy,thermal efficiency,efficiency improvement and waste recovery ratio were considered as performance parameters.A computer program was made in engineering equation solver to simulate the model.It was concluded that by the incorporation of the PDORC thermal efficiency was improved by 7-8%at reference conditions.Maximum combined cycle’s thermal and exergy efficiency were found 54.42%and 80.39%respectively of 0.95 kW/m^(2)of solar irradiation based on R1243zf working fluid.Among the results it was also found that maximum waste heat was recovered by the R1243zf about 54.22%at 0.95 effectiveness of low temperature recuperator.

Performance comparison of the solar-driven supercritical organic Rankine cycle coupled with the vapour-compression refrigeration cycle

In this study,a parametric analysis was performed of a supercritical organic Rankine cycle driven by solar parabolic trough collectors(PTCs)coupled with a vapour-compression refrigeration cycle simultaneously for cooling and power production.Thermal efficiency,exergy efficiency,exergy destruction and the coefficient of performance of the cogeneration system were considered to be performance parameters.A computer program was developed in engineering equation-solver software for analysis.Influences of the PTC design parameters(solar irradiation,solar-beam incidence angle and velocity of the heat-transfer fluid in the absorber tube),turbine inlet pressure,condenser and evaporator temperature on system performance were discussed.Furthermore,the performance of the cogeneration system was also compared with and without PTCs.It was concluded that it was necessary to design the PTCs carefully in order to achieve better cogeneration performance.The highest values of exergy efficiency,thermal efficiency and exergy destruction of the cogeneration system were 92.9%,51.13%and 1437 kW,respectively,at 0.95 kW/m2 of solar irradiation based on working fluid R227ea,but the highest coefficient of performance was found to be 2.278 on the basis of working fluid R134a.It was also obtained from the results that PTCs accounted for 76.32%of the total exergy destruction of the overall system and the cogeneration system performed well without considering solar performance.