Thermo-economic Comparison of Solar Heat Driven NH3–LiNO3 and NH3–H2O Absorption Refrigeration System

Abstract

The objective of this paper is to compare the thermal performance and evaluation of critical parameters for single effect ammonia/lithium nitrate (NH3–LiNO3) and aqua-ammonia (NH3–H2O) based absorption chiller coupled with various collectors at Ahmedabad city in India. Linear Fresnel reflector (LFR), Parabolic trough collector (PTC) and evacuated tube collector (ETC) are attached through thermally insulated storage tank to produce three ton of refrigeration (TR) at −4 °C evaporator temperature. The effect of heat source temperature on the performance parameters such as coefficient of performance (COP) and exergetic efficiency has been investigated for each chiller. Furthermore, the required optimum area and associated cost for each collector type have been determined. Thermo-economic comparison between various solar coupled absorption chillers depicted that maximum solar COP (SCOP) of ETC based system is 31.37% higher compared to that of LFR based system, whereas the cost of ETC based system is only 10.13% higher compared to LFR based system. Moreover, LFR occupies the 94% more land area for installation of solar field compared to ETC, which altogether recommended ETC coupled NH3–LiNO3 absorption refrigeration system.