After conversion losses, 13.1 quads of net electrical energy was output by power plants for general consumption.1 This amount of elec- tricity could be produced by a 100km × 100km area of high solar insolation, such as in the desert southwestern United States,
covered with solar modules with a power conversion ef ciency of 15%. In order to meet the U.S. Department of Energy cost goal of $0.33/W or $0.05–0.06/kWh for utility-scale production, these modules would need to be manufactured at a cost of $50/ m2 or less.