Modeling the performance of small capacity lithium bromide-water absorption chiller operated by solar energy

An analysis of the performance of a solar operated small capacity (two-ton) lithium bromide-water (LiBr-H₂O) absorption system is conducted. The analysis is based on the first law of thermodynamics with lithium bromide as the absorbent and water as the refrigerant. The effect of various parameters affecting the machine coefficient of performance under various operating conditions is reported. Coefficient of performance of up to 0.8 can be obtained using flat-plate solar collectors with generator temperatures in the range of 80-95°C (176-203°F). Liquid heat exchangers with effectiveness based on an NTU of the order of one would be a good design choice. The chiller can save approximately 3,456 kWh/yr per a two-ton unit, and it will reduce emissions by 19 lb of NO_x, 5,870 lb of CO₂, and 16 lb of SO_x per year per machine