PERFORMANCE OF A SOLAR SYSTEM USED FOR HEATING, COOLING AND HOT WATER PRODUCTION EMPLOYING COLORED COLLECTORS

To avoid the monotony of the black colored flat plate solar collectors, color absorbers can be used which have lower thermal efficiency than that of the usual black type collectors. In this paper a solar heating, cooling and hot water application with colored-absorber collectors of high (usual type) and low (selective) emissivity is presented. The house considered is 196 m2 insulated construction. The solar system consists of 20 m2 solar collectors and a 1000 lt storage tank. For the cooling system a LiBr absorption unit was used. The solar system provides part of the heating, cooling and hot water load for a 4-persons family. The system is simulated with TRNSYS on an annual basis at three different locations, Nicosia, Cyprus; Athens, Greece and Madison, Wisconsin. The results show that for a medium value of the coefficient of absorptance, the colored collectors give satisfactory results compared to collectors with black absorbers. This implies the use of slightly larger collector aperture area to have the same energy output as that of typical black colored collectors, which is acceptable