A compression–absorption cascade system for refrigeration is simulated with different working fluids. LiBr/H₂O is used in the absorption cycle and ammonium, R134a and carbon dioxide are evaluated in the compression cycle. First and second laws of thermodynamic analysis were analyzed with the aim of finding the best working fluid performance and appropriate operation parameters. Coefficient of performance, exergetic efficiency, irreversibility of the main components of the system, total irreversibility of the system and improvement potential were estimated for each one of the systems proposed. The results showed that the highest irreversibilities occurred in the cascade heat exchanger using carbon dioxide or ammonium, but this value decreased by using R134a. The highest value of coefficient of performance is observed by the R134a–LiBr/H₂O system when the minimum of irreversibility in the absorber and generator are reached within a range of generator temperature from 339 to 345 K. Copyright © 2013 John Wiley & Sons, Ltd.