Abstract
•A novel solar powered trigeneration energy system is proposed.•The superiority of hydrocarbons and NH3-LiNO3 as working fluid is debated.•The system performance is theoretically evaluated by energy and exergy methods.•High irreversibility rate occurs in the heliostat field, HRVG, and process heater.
The present study focuses on energy and exergy analyses of the trigeneration system consisting of heliostat field, organic Rankine cycle with the heat exchanger, and ejector-absorption chiller which has the merits of refrigerating a thermal load of below than 0 °C with solar energy more efficiently along with the generation of process heat and electric power in an eco-friendly manner. A parametric study is carried out to investigate the effect of varying the influencing operating variables on trigeneration system output, and its energy and exergy efficiencies. It is found that the exergetic output of isobutane operated system increases from 2562 kW to 4314 kW while for propane operated system it is raised from 1203 kW to 2028 kW when the direct normal irradiations are increased from 600 to 1000 W/m2. Results of energy and exergy utilization show that for isobutane ORC fluid, out of 100% solar energy supplied to the system 65.42% can be produced as energetic output and rest 34.58% is lost via thermal exhaust to ambient. On the other hand, out of 100% solar exergy supplied only 13.98% is the produced exergy, 84. 89% is the exergy destroyed due to irreversibilities, and rest 1.13% is the exergy loss.