The goal of making renewable solar energy economically competitive with conventional electric power sources is looking closer on the horizon with results being achieved by Fulton Schools researchers. Work by Assistant Research Professor Zengshan Yu, Assistant Professor Zachary Holman and Joe V. Carpenter, a graduate student research assistant, has led to technology combining silicon with another photovoltaic material — perovskite. That kind of tandem solar cell promises to exceed the efficiency of current cells in converting sunlight into energy while still being cost-competitive in the energy marketplace.