Energetic and Exergetic Performance Comparison of a Hybrid Solar Kalina Cycle at Solar and Solar Storage Mode of Operations

In this study, the energy and exergy analyses are performed to compare the performance of a hybrid solar Kalina cycle (KC) in the solar storage (SS) and solar mode of operations. The solar radiation was calculated for the geographical location of Jodhpur, Rajasthan, India, at 7 a.m. and 2 p.m. on 21 February to represent the above two modes of operation. Due to higher global radiation, the heat gain, the collector and the exergy efficiency of the parabolic trough collector (PTC) were found to be more during the SS mode of operation. Similarly, the KC also performed better in terms of net power output and exergy efficiency during the SS mode. Further, in the SS mode, water heating also could be obtained additionally. Highest irreversibility occurred in the PTC. Compared to the solar mode, the PTC irreversibility was, however, more in the SS mode. The water heater also contributed a significant amount of irreversibility. Among the KC components, the condenser irreversibility was the highest followed by the vapour turbine (VT) and the regenerator, during both the SS and solar modes of operations. The number of collectors in a single row and the rows of collector elements, the flow rate of the heat transfer fluid (HTF) and its temperature at PTC inlet finally decide the heat source temperature at inlet of the vapour generator, the mass flow rates and the net power output of the KC.