20 Jan 2009 04:01:05
'Record breaking' solar cells developed
The most efficient solar cells to date have been developed, by German scientists.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE claim that their new solar cells convert sunlight into electricity at a rate of 41.1 per cent, beating their previous record of 39.7 per cent.
Their record-breaking rate was achieved when the sunlight was concentrated by a factor of 454 and at the higher concentration of 880 they recorded efficiency of 40.4 per cent.
According to the research team 'group III-V Epitaxy and Solar Cells', their success was achieved by finding a new way to combine the component materials gallium indium phosphate and gallium indium arsenide on a germanium substrate.
This was achieved through metamorphic crystal growth which allowed the scientists to focus imperfections in the crystals into an inactive part of the solar cell.
However, the team is not alone in claiming the record.
Last year scientists at the University of Delaware claimed to have achieved 42.8 per cent efficiency.
It is that team's goal to develop cells that have 50 per cent efficiency at a cost of $1,000 (£714) per square meter, reports the EE Times.
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