Collectors with colored absorber plates are of interest to architects for applications on traditional orrnmodern buildings. The absorbers can be of blue, red-brown, green or other color. Because of thernlower collector absorptance these collectors have lower thermal efficiency than that of the usualrnblack type collectors. In this paper a solar space heating application with colored-absorberrncollectors of high (usual type) and low (selective) emissivity is presented and analyzed with respectrnto their performance, aiming to give guidelines for their wider use on buildings. The solar systemrnprovides part of the heating load. The system is simulated with TRNSYS on an annual basis at threerndifferent locations, Nicosia, Cyprus; Athens, Greece and Madison, Wisconsin. The results show thatrnthe energy output depends on the absorber darkness. For a medium value of the coefficient ofrnabsorptance, the colored collectors give satisfactory results with respect to the drop of the amount ofrncollected energy, compared to collectors with black absorbers. This implies the use of slightly largerrncollector area to have the same energy output as that of typical black colored collectors, which isrnacceptable.
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