Comparative assessment of four novel solar based triple effect absorption refrigeration systems integrated with organic Rankine and Kalina cycles

Abstract

In this study, the performances of four novel solar integrated systems are compared with the help of energy and exergy analyses. The systems either use a single unit or two units of a triple effect absorption refrigeration system for cooling production through utilization of hot water obtained at the solar collector exit. The power cycles are based on organic Rankine and Kalina cycles. For the systems with two absorption refrigeration system units, it was found that when the system is integrated with the Kalina cycle, it provides better performance in terms of power, efficiency and irreversibility rate. At solar radiation intensities of 640 W/m2 (low) and 950 W/m2 (high), the net powers obtained from the Kalina cycle are respectively 7.17% and 7.35% more while its irreversibility are 16.23% and 16.28% less compared to those of an R245fa operated organic Rankine cycle. In a different arrangement, when one unit of the absorption refrigeration system is replaced by another isopentane based organic Rankine cycle, no doubt the cooling output reduces but the net power of the system with one organic Rankine cycle (isopentane based) and one Kalina cycle increases in an average by 22.82%at the two solar radiation intensities. This increase in average net power output is however less (9.84%) for the system with two organic Rankine cycles.