Long-term optical stability of fluorescent solar concentrator plates

Fluorescent solar concentrators offer an alternative approach for low-cost photovoltaic energy conversion. For successful application, not only the power conversion efficiency and cost are important, but also lifetime or stability of the devices. As today's concentrator is made of polymer sheets containing organic dyes, which are known to be sensitive to degradation in the presence of light and oxygen, the lifetime under outdoor conditions has been under discussion. This paper shows that depending on the dye and the polymer sheet material, rather stable sheets can be made with < 1% loss in absorption after 6.5 years outdoor exposure. Outdoor roof setup for lifetime testing of fluorescent flat plate concentrators.