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New solar cell efficiency record set

New solar cell efficiency reco...
New world record solar cell (Image: Fraunhofer ISE)
New world record solar cell (Image: Fraunhofer ISE)
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New world record solar cell (Image: Fraunhofer ISE)
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New world record solar cell (Image: Fraunhofer ISE)

January 27, 2009 Researchers at the Fraunhofer Institute for Solar Energy Systems ISE have set a new record for solar cell efficiency. Using concentrated sunlight on a specially constructed multi-junction solar cell, the research group lead by Frank Dimroth has achieved 41.1% efficiency for the conversion of sunlight into electricity.

The breakthrough, which surpasses the 40.7 percent efficiency previously demonstrated by Spectrolab , involved the use of sunlight concentrated by a factor of 454 and focused onto a small 5 mm multi-junction solar cell made out of GaInP/GaInAs/ Ge (gallium indium phosphide, gallium indium arsenide on a germanium substrate). Even at a higher sunlight concentration of 880, an efficiency of 40.4% was measured.

"We are elated by this breakthrough," says Frank Dimroth, head of the group "III-V - Epitaxy and Solar Cells" at Fraunhofer ISE. "At all times the entire team believed in our concept of the metamorphic triple-junction solar cells and our success today is made possible only through their committed work over the past years."

Multi-junction solar cells combine semiconductor compounds in layers to absorb almost all of the solar spectrum. The problem is that in combining these materials in a process known as metamorphic growth, defects occur in the lattice structure making it difficult to grow the III-V semiconductor layers with a high crystal quality. The Fraunhofer ISE researchers have overcome this issue by discovering a way to localize these defects in a region of the solar cell that is not electrically active, meaning that the active regions stay relatively defect free and higher efficiencies can be achieved.

"The high efficiencies of our solar cells are the most effective way to reduce the electricity generation costs for concentrating PV systems," says Dr. Andreas Bett, Department Head at Fraunhofer ISE. "We want that photovoltaics becomes competitive with conventional methods of electricity production as soon as possible. With our new efficiency results, we have moved a big step further towards achieving this goal!"

Via: Fraunhofer Institute for Solar Energy Systems ISE (http://www.ise.fraunhofer.de/)

4 comments
Anumakonda Jagadeesh
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE achievement of 41.1% efficiency for the conversion of sunlight into electricity is indeed a major breakthrough in Solar Technology. ISEs reputation in Solar Technology is well known and they are world leaders. It is hoped this high efficiency will pave the way for wider application of solar power generation around the globe. Congratulations ISE for this great achievement. Dr.A.Jagadeesh Nellore (AP), India.
Andrew M
I wish these reports would mention the light spectrum (AM0, AM1, AM1.5 etc.).
Ronald Cooper
Are these defects located around purpossed nucleation sites, like seeding a cloud?
Eric Nueman
They\'re talking now about 80% and that will just about do it for the electricity producing market for individual homes & travel homes! There will be no more need for dangerous plutonium run electricity factories! If man continues to insist on nuclear power stations being built, they will be in great danger if any of them implode like in Japan for any reason! So the sooner this solar revolution winds up to 80% efficiencies, the sooner natural means of supplying electricity will overcome existing means that pollute the earth! It may already be too late as there are forces trying to limit this energy revolution of oil control reasons and money making is the culprit! --e