Absorption cooling systems due to having the capability of using renewable and waste energy sources and also working with environmentally friendly refrigerants have fascinated many researchers as potential alternatives to traditional vapor compression cooling systems. However, the performance of these systems still lower than those of traditional ones. The refrigerant mixture can play a crucial role in improving the performance of these systems. In this regard, for the first time, the effects of using ethyl ether-acetaldehyde as a working pair in a 0.5 kW solar-driven absorption refrigeration system integrated by a parabolic trough solar concentrator are experimentally examined. The experiments are conducted on certain days in October at Babylon University, Iraq. The performance of the proposed hybrid system using ethyl ether-acetaldehyde is compared with a similar one with a common pair of lithium bromide (LiBr-water). Moreover, the operating conditions of the main system components in terms of temperature and pressure are discussed. The results show that the ethyl ether-acetaldehyde solution can operate under a low hot water temperature of 78 °C supplied by the solar collector and produce chilled water with a temperature of 7 °C. While for a hot water temperature of 90°C produced by the solar collector, the system with LiBr-water pair can produce chilled water with the temperature of about 16 °C. Therefore, the ethyl ether-acetaldehyde solution can be suitable for areas with hot and moderate temperatures. Moreover, the coefficient of performance improves from 0.64 to 0.78 by using ethyl ether-acetaldehyde as working pair instead of LiBr-water.

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