We recommend coatings for panels based on your durability, cost and design constraints. The four options are :
Polyurethane: Highly UV resistant and durable. Our polyurethane solar panels can last up to 10 years in the sun with minimal power degradation. The polyurethane coating is poured or "potted" onto the solar cell to form a highly water resistant panel. Each individual cell is completely encapsulated with polyurethane.
ETFE: Economical, waterproof and UV resistant, but shorter life than polyurethane. Solar cells are attached to a substrate and then laminated by EVA and ETFE under heat and pressure. Using premium materials (there are differences in the production quality of ETFE and EVA), our ETFE solar panels have an expected life span of 5-7 years outdoors.
Epoxy or PET: Panels made with these coatings are inexpensive, but we do not recommend this coating for most industrial applications because it tends to have a relatively short life span. They are the least UV resistant of all options.
Glass: With high UV resistance, combined with the frame, glass panels can have the longest service life. On a per-watt basis, glass panels are the heaviest.