Solar energy is an integral part of our renewable energy game plan. Yet as useful as solar is, their efficiency has always seemed incredibly low. Who would consider 15-25 percent “good” if it were your electricity delivery?
Now researchers at the Fraunhofer Institute for Solar Energy Systems ISE, along with Soitec, CEA-Leti and the Helmholtz Center Berlin (Germany) have achieved a new world record for converting sunlight into electricity using a new solar cell structure with four solar subcells. After three years, they have reached new record efficiency of 44.7 percent of solar conversion from ultraviolet through to the infrared, into electrical energy.
“We are incredibly proud of our team which has been working now for three years on this four-junction solar cell,” says Frank Dimroth, Department Head and Project Leader in charge of this development work at Fraunhofer ISE. “This four-junction solar cell contains our collected expertise in this area over many years. Besides improved materials and optimization of the structure, a new procedure called wafer bonding plays a central role. With this technology, we are able to connect two semiconductor crystals, which otherwise cannot be grown on top of each other with high crystal quality. In this way we can produce the optimal semiconductor combination to create the highest efficiency solar cells.”
Could this mean that future solar panels will be miniaturized – and that the need for huge solar arrays will be eliminated? For more on this tantalizing breakthrough, check out http://bit.ly/1frugy5.