The broader impact/commercial potential of this Small Business Innovation Research (SBIR) Phase I project is on renewable electricity production by large scale utilities. Today large scale solar generation (the majority of all solar energy) is almost exclusively by large farms of photovoltaic (PV) panels made from silicon cells, as used also for rooftop solar. The research is aimed at enhancing scientific and technological understanding of an alternative approach that exploits a different, much more efficient type of PV cell. It promises lower cost electricity in sunny climates around the world, from longer lived plants using less land. The potential societal impact is broader adoption of solar electricity both in the US and across the world, and thus reduced global pollution. The commercial impact of the project is also huge. In the targeted global market, $30 billion now is spent annually on new solar installations and an increase to $100 billion is projected. This is an opportunity for the US to re-establish itself as a world leader in solar manufacturing, of both the different PV cells that underlie our approach, and the optical and mechanical systems that are the target of this research and are key to cost reduction. The proposed project will explore a new approach to solar electricity generation, using advanced photovoltaic (PV) cells that convert sunlight into electricity with twice the efficiency of silicon PV panels. The innovation is in the system used to focus sunlight on the cells as needed for highest efficiency at lowest cost. The advanced PV cells themselves have already been developed for spacecraft, but previous efforts to commercialize them for ground use have failed, because the systems needed to provide concentrated sunlight were too expensive. The research will be directed to developing, building and testing the two innovative elements critical to a complete, low cost system: 1) Small glass lens arrays used at the focus of large dish reflectors to apportion sunlight equally onto individual small cells. Existing commercial glass molding methods do not yield arrays of the size and precision needed; a new molding method tailored specifically for the task will be developed. 2) A novel mechanical structure will be developed to orient the mirrors toward the sun throughout the day with minimal use of steel, by employing an efficient spaceframe structure turning on a ground track, and a sensor-feedback system to eliminate conventional, heavy, rigid bearings. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
