Paul Alivisatos, co-leader of Berkeley Lab's Helios Project, is the Associate Director for Physical Sciences and director of the Materials Sciences Division at Berkeley Lab. In the Helios Project, Alivisatos will use nanotechnology in the efficient capture of sunlight and its conversion to electricity to drive economical fuel production processes. He is an authority on artificial nanostructure synthesis and inventor of the quantum dot technology. His talk was presented May 14, 2007.