Long-term photothermal/humidity testing of photovoltaic module polymer insulations and cover films

Abstract

C a l i f o r n i a I n s t i t u t e o f TechnologylJet P r o p u l s i o n L a b o r a t o r y Pasadena, Cal i f o r n i a ABSTRACT The l i f e expectancies o f T e d l a r and o t h e r p o l ymer f i l m s considered f o r use as cover m a t e r i a l s i n t e r r e s t r i a l p h o t o v o l t a i c modules, were i n v e s t i g a t e d by exposing them f o r more t h a n 13000 hours on an outdoor t e s t stand and f o r up t o 10000 hours i n several a c c e l e r a t e d mu1 t i -s t r e s s environments. Visual observations, and d i a g n o s t i c analyses o f weight and mechanical s t r e n g t h losses, were p e r i o di c a l l y conducted t o assess t h e n a t u r e and r a t e o f degradation o f mechanical p r o p e r t i e s and t o assess t h e e f f e c t s o f f i l m t h i c k n e s s and UV s t a b i l i z e r content. degraded m a t e r i a l s l i n k e d weight and mechanical p r o p e r t i e s l o s s e s t o t h e u n d e r l y i n g photo-thermal/photo-oxidation chemistry.

PV Reliability Development Lessons From JPL's Flat Plate Solar Array Project

“…5, increased temperature was found to be a highly predictable accelerator, following a classic Arrhenius dependence [5]. This led to the recognition that a useful accelerated test could involve extended exposure at 1-sun UV, together with a carefully controlled elevated temperature such as 85 to 100 • C [23].…”

“…These we refer to as the reliability technology base that was developed during the FSA tenure. Key technology base contribution areas are noted in Table V and are heavily documented in nearly 400 reports that are organized by technical topic in top-level summaries [1], [2], [16], [21]- [23], [26].…”