World Record Solar Cell with 44.7% Efficiency
World record solar cell with 44.7% efficiency, made up of four solar subcells based on III-V compound semiconductors for use in concentrator photovoltaics. ©Fraunhofer ISE
With a solar cell efficiency of 44.7%, scientists around Dr. Frank Dimroth at the Fraunhofer Institute for Solar Energy Systems ISE achieved a new world record for the conversion of sunlight into electricity. They used a new solar cell structure with four solar subcells, a new procedure called wafer bonding and optical components which concentrate the sunlight (Concentrated Photovoltaics CPV). Part of the cell structure was developed at the Helmholtz Zentrum Berlin in the research group of Prof. Thomas Hannappel, (now with Technical University Ilmenau). They developed methods to prepare critical interfaces and to avoid undesirable defects. SOITEC and CEA-Leti have as well contributed to this world record.
An efficiency of 44.7% was measured at a concentration of 297 suns. This indicates that 44.7% of the solar spectrum`s energy, from ultraviolet through to the infrared, is converted into electrical energy. Concentrator photovoltaics has the potential to achieve twice the efficiency of conventional PV power plants in sun-rich locations of the globe.
Further Information:
www.ise.fraunhofer.de
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