Fraunhofer ISE achieves 35.9% efficiency for III-V triple-junction solar cell based on silicon The cell, which looks externally like a device with a two-terminal architecture, was built with III-V semiconductor layers that were connected to the silicon sub-cell on the atomic level. The cell may be used in electrically powered aircraft and drones.Germany's Fraunhofer Institute for Solar Energy Systems ISE claims to have achieved a 35.9% conversion efficiency rate for a III-V monolithic triple-junction solar cell based on silicon. "This value measured under the terrestrial AM1.5g spectrum sets a new world record and demonstrates the potential of silicon-based tandem photovoltaics," the research ...