New Cost Efficient Components for the Encapsulation of Photo-Voltaic Modules

The commonly used incapsulating system for crystaline Si-based photo voltaic (PV) modules is: glass/ethylene vinyl acetate (EVA)/Solar cells/EVA and at the rear side protected by a polyester (PET) - Aluminum - Tedlar (PVF) foil. This system serves to provide structural support, electrical insulation and protects the solar cells from environmental impact such as moisture and is found to be environmentally stable for at least 20 years in operation. This paper focuses on a new generation of cost reduced high barrier films protecting front and rear sides of photo voltaic cells against moisture. The encapsulating front and rear side film systems possess a moisture permeability lower than 0.1 g/m2 d and prevent electrical insulation problems, because all materials are dielectrics. Especially by using transparent film systems as front side encapsulation, a further reduction of the total costs can be obtained accompanied by a high functionality of the film systems. The cost savings in the fiel d of materials, accompanied by a higher productivity at the assembly step will help to expand the market volume of photo voltaic panels.