Alternative PV module encapsulation materials and schemes

The stabilization effects of various superstrate materials against UV‐induced EVA discoloration and the effect of photocurrent enhancement by white light‐reflecting substrates are summarized. Based on the results, some alternative PV module encapsulation schemes are proposed for improved module performance, where the current or modified formulations of EVA encapsulants still can be used so that the typical processing tools and conditions need not to be changed significantly. The schemes are designed in an attempt to eliminate or minimize the EVA yellow‐browning and to increase the module power output. Four key experimental results from the studies of EVA discoloration and encapsulation are to employ: (1) UV‐absorbing (filtering) glasses as superstrates to protect EVA from UV‐induced discoloration, (2) gas‐permeable polymer films as superstrates and/or substrates to prevent EVA yellowing by permitting photobleaching reactions, (3) modified EVA formulations, and (4) internal reflection of the light by white substrates.