Accelerated UV-aging of acrylic materials used in PV concentrator systems

This paper reports the results of a systematic study comparing the optical properties of two acrylic formulations as a function of accumulated ultraviolet (UV) exposure. Outdoor weathering was done at DSET Laboratories using real-time and accelerated testing for a period of 5 years. Accelerated UV exposure (/spl sim/20-suns) was conducted at Sandia National Laboratories using the filtered spectrum of a xenon arc lamp. A detailed comparison between filtered-lamp spectra and outdoor solar irradiance is presented showing the importance of the 300-325 nm wavelength range when comparing results of outdoor and indoor UV exposure. Additional optical properties data are presented for acrylic materials that have undergone real-time exposure at Sandia for 36.5 years.<
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