Solar energy researchers from around the nation participated in a closed conference October 12-15, 2010 at Biosphere 2. Though the conference was closed to the public, videos of keynote speeches are available from Roger Angel, of Steward Observatory, University of Arizona; Nate Lewis, of the California Institute of Technology; Eric Mazur, of Harvard University; and Arun Majumdar, director of the U.S. Department of Energy's Advanced Research Projects Agency - Energy (ARPA-E).