New York NY (SPX) Jan 11, 2011
In recent years, developers have been investigating light-harvesting thin film solar panels made from nanotechnology - and promoting efficiency metrics to make the technology marketable. Now a Tel Aviv University researcher is providing new evidence to challenge recent "charge" measurements for increasing solar panel efficiency.
Offering a less expensive, smaller solution than traditional panels, Prof. Eran Rabani of Tel Aviv University's School of Chemistry at the Raymond and Beverly Sackler Faculty of Exact Sciences puts a lid on some current hype that promises to increase efficiencies in thin film panels.
His research, published recently in the journals Nano Letters and Chemical Physics Letters, may bring the development of new solar energy technologies more down to earth.
Prof. Rabani combines a new theoretical approach with computer simulations. "Our theory shows that current predictions to increase efficiencies won't work. The increase in efficiencies cannot be achieved yet through Multiexciton Generation, a process by which several charge carriers (electrons and holes) are generated from one photon," he says.
Inefficient as "charged"
A chemical physicist, Prof. Rabani investigates how to separate charges from the sun efficiently. In 2004, physicists suggested that more than one electron-hole pair could be pulled from one photon in a complicated process in semiconductor nanocrystals.
If this were possible, the charge would be doubled, and so the solar energy efficiency would increase. "We've shown that this idea doesn't work," Prof. Rabani says.
One step closer to marketing the sun
Typically, one photon from the sun absorbed in a thin film solar panel can excite one electron-hole pair, which is then converted to electricity.
Currently there are claims that if more electron-hole pairs can be excited after the photon is absorbed, a larger fraction of the photon energy can successfully be converted into electricity, thus increasing device efficiency.
The theory that Prof. Rabani developed with his Israeli colleagues shows why this process is not as efficient as originally conceived.
It's bad news for panel producers looking to create more efficient solar panels, but good news for researchers who are now free to look to the next realistic step for developing a technology that works.
Prof. Rabani is now on sabbatical at the University of California, Berkeley as a Miller Visiting Professor.
Share This Article With Planet Earth
Tel Aviv University
All About Solar Energy at SolarDaily.com
Oslo (AFP) Jan 10, 2011
Norwegian conglomerate Orkla said Monday it was in talks to sell its metals company Elkem to a Chinese silicon company, reportedly for up to two billion euros ($2.6 billion), a sign of easing tensions between the two countries since the 2010 Nobel Peace Prize. "Orkla ASA hereby confirms that it is in negotiations with China National Bluestar regarding a possible sale of Elkem AS' silicon-rel ... read more
Study Estimates Land Available For Biofuel Crops|
Pratt And Whitney Military Engines Power Biofuel Tests For USAF
Global biofuel land area estimated
Biofuel Grasslands Better For Birds Than Ethanol Staple Corn
Robotic ball a hit at electronics show
Robots massage, clean, and amuse at CES
Sugar And Spice
The 2011 FIRST Robotics Competition
China first in wind power capacity
Siemens, Dong, test new offshore turbines
Egypt to invite tenders for wind farms
Keenan 2 Wind Farm Commences Commercial Operation
No Left Turn: 'Superstreet' Traffic Design Improves Travel Time, Safety
Japanese carmakers in push for hydrogen vehicles
16 dead, 23 hurt in China road accident
Philippine traffic woes worsen as car sales boom
Australia's flood-hit Gladstone port to resume coal exports
Brazil mulls underwater base to guard oil
China gives DRCongo 52-mln-dlr donation
Wave Power Could Contain Fusion Plasma
New Research Shows How Light Can Control Electrical Properties Of Graphene
EPA to defer greenhouse gas permitting
Obama to regulate carbon from power plants
Romania in talks with Japan on trading carbon credits
Texan builds artful, green homes out of trash
Poll: Americans not as green
Security industry priority becomes law
Bjork's karaoke marathon boosts anti-takeover petition count
Indonesia president talks tough on forest destroyers
Canada invests Can$278 million in 'greener' paper
Predicting Tree Failures And Estimating Damage From Diseased Trees
Indonesia picks Borneo for forest preservation scheme
|The content herein, unless otherwise known to be public domain, are Copyright 1995-2010 - SpaceDaily. AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by SpaceDaily on any Web page published or hosted by SpaceDaily. Privacy Statement|