Parametric study of solar power tower driven combined supercritical CO2 cycle and organic Rankine cycle using low GWP fluids

In this study, parametric analysis of the solar power tower (SPT) driven combined recuperated supercritical CO2 Brayton cycle and organic Rankine cycle (ORC) were carried out. Further, low global warming potential and zero ozone depletion fluids were considered in bottoming ORC to reduce harmful effects on environment. A computer program was made in engineering equation solver for simulation. The effects of the SPT design parameters such direct normal irradiation (DNI), concentration ratio (CR), receiver emittance and heat transfer fluid velocity on the system performance were investigated. It was found that thermal performance increased with DNI, CR and heat transfer fluid velocity while decreased with receiver emittance. At 0.95 kW/m2 of DNI, R1224yd(Z) achieved the highest exergy efficiency, thermal efficiency and net power output of 58.52% and 54.43% and 293.50 kW, respectively