Analysis of organic rankine cycle powered by N-number of solar collectors in series

Thermodynamic model of the solar power organic Rankine cycle (ORC) has been proposed in the present study. Model is developed in MATLAB 2018a for Cyclohexane/R123 mixture-based ORC system driven by series of N-collectors. Four different collector models namely: Case-I, N series connection of photovoltaic thermal conventional compound parabolic (NPVTCCPC) collector system; Case-II: N series connection of photovoltaic thermal (NPVT) collector system; Case-III: N series connection of conventional compound parabolic collector (NCCPC) system; Case-IV N series connection of flat plate collector (NFPC) system have been integrated with ORC system. Overall thermal performance has been evaluated for each case and compared individually. Case-III (NCCPC) emerged as the best combination in the view of highest collector exit temperature 110 degrees C, heat gain 255 kW, thermal efficiency 14.14%, exergetic efficiency 54.77%. Further, highest percentage of total exergy destruction was observed in evaporator (37-45%) followed by condenser (28-31%), expander (24-30%) and lowest in pump (1-2%). The present developed system could be a promising solution to power crises in remote and off-grid-connected areas.

Automated summary

In this study, a thermodynamic model of the solar power organic Rankine cycle (ORC) was proposed. The model was developed in MATLAB 2018a for a Cyclohexane/R123 mixture-based ORC system driven by a series of N-collectors. Four different collector models were integrated with the ORC system and evaluated for their thermal performance. The results showed that the N-series connection of conventional compound parabolic collector (NCCPC) system performed the best, with the highest collector exit temperature, heat gain, thermal efficiency, and exergetic efficiency.