Researchers develop low-cost technique to double solar energy
05 Nov 2012
In order to enhance solar energy's potential, Andreas Bett of the Fraunhofer Institute for Solar Energy Systems ISE in Freiburg and Hansjörg Lerchenmüller, general manager of Soitec solar GmbH have developed concentrator photovoltaic systems based on multijunction solar cells, and deployed them for industrial use.
This effectively makes photovoltaic technology even more efficient and more affordable, an achievement for which the two innovators were awarded Germany's most highly-endowed award 2012 DBU German Environmental Award (DBU Deutscher Umweltpreis), that offers € 500,000
This system is capable of converting almost twice the available sunlight into electricity as compared to conventional silicon-based systems.
Yet how does one manage to double power output using multi-junction solar cells? Conventional solar cells made of silicon are unable to convert the entire solar spectrum into power.
The two experts in photovoltaics therefore used an array of different semi-conducting materials. They stacked layers of gallium indium phosphide, gallium indium arsenide and germanium in layers, which allows them to capture the sun's almost entire energy.
Three years ago, the research team under Bett achieved a degree of efficiency equal to 41.1 per cent – a world record at the time.