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A simple effect one stage ammonia-water absorption cooling system fueled by solar energy is analyzed. The considered system is composed by a parabolic trough collector concentrating solar energy into a tubular receiver for heating water. This is stored in a fully mixed thermal storage tank and used in the vapor generator of the absorption cooling system. Time dependent cooling load is considered for the air conditioning of a residential two-storey house. A parametric study is performed to analyze the operation stability of the cooling system with respect to solar collector and storage tank dimensions. The results emphasized that there is a specific storage tank dimension associated to a specific solar collector dimension that could ensure the longest continuous startup operation of the cooling system when constant mass flow rates inside the system are assumed. [ABSTRACT FROM AUTHOR]

This paper presents a review of exergy analysis of solar thermal collectors and processes. It includes not only various types of solar collectors, but also various applications of solar thermal systems. Initially the fundamentals of second law analysis are briefly presented as well as the exergy of solar radiation, which is the input to any solar system. Concentrating and non-concentrating collectors have been analyzed, including parabolic dish and parabolic trough collectors from the first category, and flat-plate collectors, air solar heaters, and evacuated tube collectors from the second category. Hybrid photovoltaic/ thermal collectors have also been examined. Applications and processes include the use of phase change materials either in the collection or storage of thermal energy, drying, heating, multigeneration, trigeneration, solar cooling, solar assisted heat pumps, domestic cogeneration, hydrogen production, hybridization with other renewables, solar ponds, power plants and desalination/distillation. Through literature review on the above subjects it is shown that exergy analysis, which gives a representative performance evaluation, is emphasized as a valuable method to evaluate and compare possible configurations of these systems. [ABSTRACT FROM AUTHOR]