Standardizing Accelerated Aging Testing Conditions for Silvered-Glass Reflectors

Abstract

To assure the quality of accelerated aging tests for solar concentrators, their standardization is crucial. It guarantees the employment of adequate testing, measurement and characterization procedures and the comparability between results. A committee of the Spanish AENOR standardization agency is working on the draft “Reflector Panels for Concentrating Solar Technologies”. This work focuses on the evaluation of the procedures defined in this standard. The reflector material from the Japanese company Nishio Glass Mirror Co., which showed severe degradation after 7 years of outdoor exposure in Abu Dhabi, is tested according to the AENOR standard to check if its poor outdoor performance could have been predicted by accelerated aging testing. However, after completion of the accelerated tests, in some cases even for considerably longer test durations than the minimum required by AENOR, no considerable degradation was detected. The results suggest that the proposed testing program by AENOR is not aggressive enough to identify material failure. Ways to improve the current standard are proposed through development of more realistic tests.