Solar-powered chilling for Tunisian climate: technical and economical analysis of individual air-conditioning units driven by different collectors

Abstract

This paper aims to analyse the technical and economical feasibility of solar driven air-cooled single effect LiBr-H2O absorption domestic chillers adapted to Mediterranean climatic conditions and in particular to Tunisia. The solar cooling system is dynamically simulated with TRNSYS. The analysis is performed for two types of solar collectors: flat plate collectors and evacuated tube collectors. A parametric analysis is carried out in order to evaluate the sensitivity of the optimum collector area to relevant economical parameters. The technical and economical investigation show that the solar system coupled to the flat collectors is more economical than the system coupled to the evacuated tube collectors despite better efficiency of the latter. In fact, the optimum evacuated tube collector area is 32 m2 with a solar fraction of 72.6% and total annual cost, 1,935.6 €. The optimal flat collector area is 50 m2, the corresponding solar fraction, 62.7% and the amount of annual total cost is 1,862 €. The results depend on fluctuant economical parameters. The sensitivity study shows that the optimum solar collector area is more sensitive to the unit price of the collectors.