A qualitative study and field performance for a fluorescent solar collector

A fluorescent solar collector (FSC) based on Perylene-dye doped in poly (methyl methacrylate) (PMMA) has been suggested. A qualitative study shows that the Perylene dye with high fluorescence quantum yield and large Stokes shift can be used as a good activator for a FSC. After the FSC has been exposed to daylight illumination for one season (Summer 2000), the fluorescence quantum yield decreased and a new fluorescent band appeared. This new band is due to the dimers that exist only in the excited state (excimers). Also, the absorption spectra of Perylene dye was shifted to a longer waveleugth by exposure to sunlight, this leads to more overlapping between absorption and emission spectra and decreased the optical efficiency of the FSC. The optical efficiency of the FSC was measured and calculated hourly for one season. The average values of the optical efficiency for three positions were higher than those obtained in previous work. The photodegradation of the Perylene dye after 32 weeks exposure to daylight shows two decomposition rates. (C) 2002 Elsevier Science Ltd. All rights reserved.