LOW-COST ENCAPSULATION MATERIALS FOR TERRESTRIAL SOLAR-CELL MODULES

Solar cell modules must undergo dramatic reductions in cost in order to become economically attractive as practical devices for the production of electricity. A federal goal seeks to have, by 1986, an industrial capability of producing solar cell modules at a cost of 50¢ per W (in 1975 dollars) and a service lifetime of 20 yr. Today's modules cost more than $11.00 per W, and they have an undefined lifetime. Part of the cost reductions must be realized by the encapsulation materials which are used to package, protect, and support the solar cells, electrical interconnects, and other ancillary components. It is estimated that to meet a cost goal of 50¢ per W, encapsulation materials, including the structural substrate or superstrate, should cost between $2.70 and $5.00 per m2 of module area (in 1975 dollars). This article presents the findings of material surveys intended to identify low cost materials which could be functional as encapsulants. This article further assesses the prognosis for achieving an encapsulation system at the lower cost goal of $2.70 per m2, and identifies the technologies which must be advanced or developed to achieve 20-yr life with the lowest costing materials. © 1979.