Quality control of EVA encapsulant in photovoltaic module process and outdoor exposure

The objective of this work is to understand the physical and chemical properties of the standard cure copolymer ethylene-vinyl-acetate (EVA), used as encapsulant, during photovoltaic module encapsulation process and also in field exposure of Algerian Sahara as specific desert climate. EVA samples are characterized by gel content measurements (crosslinking test), dielectric spectroscopy as function of temperature and frequency, thermally stimulated current (TSC), UV–visible–near infrared transmittance spectrometry to detect the quality of the material. Results show a decrease in most properties of EVA in natural field exposure due principally to the specificity of the region characterised by hot and dry climate.

Transmission (%) Original Before exposure After exposure Wavelength (nm) Fig. 15. UV–visible spectra of EVA.