Concurrent optimization and 4E analysis of organic Rankine cycle power plant driven by parabolic trough collector for low-solar radiation zone

Abstract

The Organic Rankine Cycle driven by parabolic trough collectors for the low-solar radiation zone was investigated in this study. Six environment-friendly refrigerants namely R152a, R600a, R601a, cyclopentane, cyclohexane, toluene were evaluated. In addition, the conventional Rankine cycle was evaluated. The dynamic energy and exergy analysis based on the daily average solar data was conducted. The system was designed in a combination solar field, thermal energy storage subsystem, and power block for 24 h of working time without any external energy source. The designed system was concurrently optimized through the economic indicator namely net present value since all the parameters depend on each other. The best design was obtained for conventional cycle with a net present value of 9.012 million US$. The optimum pressure and temperature of the turbine inlet were determined as 3250 kPa and 380 oC, respectively. The optimal ratio of the heat transfer fluid was found around 34.1%. The maximum energy and exergy efficiencies were respectively obtained as 11.05% and 11.86%. These values were respectively conducted as 10.19% and 10.94% at the design point. It was also conducted that the reductions in the emissions of CO2, SO2, and NOx were 108,046.4 ktones, 2,457.6 ktones, and 249.7 ktones, respectively.