Third generation photovoltaics

While the photovoltaics industry is currently dominated by silicon wafer-based "first generation" technology, there is a clear move towards "second generation" thin-film technology. Second generation technology has significant cost advantages over wafer-based modules, due to reduced materials usage and large-area processing. Even with second generation technology, however, materials costs are likely to eventually dominate. To further reduce cost, a third-generation of high efficiency thin-film technology will be necessary, with energy conversion efficiencies double or triple the 15 to 20% presently targeted. Tandem cells are the best known example of such approaches, but a range of more integrated approaches is possible, as described in this paper.