In the present era, there has been a significant interest in energy conservation that has prompted a new methodology. This has brought a relative change to the critical analysis of almost all thermodynamic processes and installations. There has been a development of concepts in relation to the second law of thermodynamics. As the analysis and design of engineering systems based on only the first law is not entirely adequate. This is caused by factors such as the application of materials balances, energy balances and equilibrium relationships which do not adequately show how effectively a system utilises given energy resources.
Energy and exergy methods are well-established methods, which are used to study energy conversion processes [1]. The exergy method, known as the second law analysis, calculates the exergy loss caused by irreversibility, which is an important thermodynamic property which measures the useful work that can be produced by a substance, or the amount of work needed to complete a process. Unlike energy, exergy is not conserved; analysis of exergy losses provides information as to where the real inefficiencies in a system lie.
In this paper, the exergy losses inherent in an absorption refrigeration system are calculated. A design procedure has been applied to a lithium-bromide absorption cycle and an optimisation procedure that consists of determining the enthalpy, temperature, mass flow rate, heat rate, exergy losses in each component, coefficient of performance and overall efficiency has been performed. An availability analysis was carried out for each component in the system.