1. National Renewable Energy Laboratory, Golden, Colorado, USA
2. Lawrence Berkeley National Laboratory, Berkeley, California, USA
3. University of Washington, Seattle, Washington, USA
4. Sandia National Laboratories, Albuquerque, New Mexico, USA
5. University of Wisconsin, Madison, Wisconsin, USA
6. Iowa State University, Ames, Iowa, USA
7. U.S. Department of Energy Solar Technologies Office, Washington, D.C., USA