Significance of Spectral Correction of Collector Measurements Performed in Solar Simulators
M¨šller-sch?ll, C., Brunold, S. and Frei, U.
2002 EUROSUN 2002
M¨šller-sch?ll, C., Brunold, S. and Frei, U., (2002), "Significance of Spectral Correction of Collector Measurements Performed in Solar Simulators", EUROSUN 2002.
Abstract:
The efficiency curve of a solar thermal collector was measured at two different institutes. One institute used natural sunlight, the other artificial light. The difference of efficiency curves was about 5 %. The reason for the difference was the lack of a spectral correction of the indoor measurement which should have accounted for the spectral differences of the light sources. This correction is an established procedure in all relevant standards.As examples, correction factors for different combinations of absorbers and glazings are presented. These figures prove that spectral corrections for indoor measurements are significant and may not be omitted. The measurements necessary for the correction, namely absorbtance, transmittance and the spectrum of the light source have to be an integral part of the collector measurement and must be an integral part of the competence of an indoor testing lab.
