Scientists at NREL and at Swiss Center for Electronics and Microtechnology (CSEM) jointly set new world record for converting non-concentrated (1-sun) sunlight into electricity using dual-junction III-V/Si solar cell. At 29.8%, newly certified efficiency was set using top cell of gallium indium phosphide, developed by NREL, and bottom cell of crystalline silicon, which was developed by CSEM using silicon heterojunction technology. Both cells were made separately and then stacked by NREL.