In the case that an absorption cycle is driven by using waste heat as a heat source, it is efficient for the improvement of exergy efficiency to decrease the temperature in regenerators. In this paper, two methods of decreasing the temperature in high-temperature regenerator of double-effect cycle were evaluated based on the energy and the exergy analysis. Those are parallel flow systems, in which aqueous solution is fed to high-and low-temperature regenerators individually, and hybrid cycle with a steam compressor placed at the exit of a low temperature regenerator in order to decrease the dew point of the low temperature regenerator. As a result, it was shown that performance characteristics of LiBr-water absorption cycle is strongly dependent on the difference of solution concentration between the inlet and the exit of the absorber, the maximum value of COP is obtained at 63 wt% at the inlet of the absorber for all cycles, and the temperature in high-temperature regenerator can be decreased by 14°C for decreasing of 10°C of dew point in low-temperature regenerator without decreasing in COP by utilizing the hybrid system.
