Terrestrial Photovoltaic Research and Development

Developing practical photovoltaic (PV) devices for the conversion of sunlight into electricity on earth requires R&D to build on the knowledge acquired during the successful space-PV development program. It also requires new generations of materials and structures specifically designed for the terrestrial environment. Silicon ribbon technology has had marked success as an adaption of the singlecrystal and polycrystalline silicon technologies. A new generation of terrestrial PV technologies is emerging based on single-and multijunction thin-film flat plate and concentrator systems. These are the technologies being emphasized in the research program conducted by the Solar Energy Research Institute as part of the U.S. Department of Energy's National Photovoltaics Program. This paperexamines the status of silicon ribbons, thin films, and concentrators, as well as their application in various potentially high-performance, cost-competitive structures.