Researchers Developing More Powerful Solar Cells

Sep 18, 2006

Sure, Iowa has its share of rainy, snowy and cloudy days. But look out the window. “We have a lot of sunlight,” said Vikram Dalal as sunshine lit up a late-summer morning and the south-facing windows of his office at Iowa State University’s Applied Sciences Complex.

Dalal, the director of Iowa State’s Microelectronics Research Center and the Thomas M. Whitney Professor in electrical and computer engineering, has spent more than three decades finding ways for that sunlight to generate more and more electricity. He thinks his latest project can boost the performance of an Iowa company’s solar cells by 40 to 50 percent.

Dalal is working with PowerFilm Inc., an Ames company that manufactures thin, flexible solar panels, to improve the performance and stability of the company’s solar cells. The project is partially supported by a $63,406 grant from the Grow Iowa Values Fund, a state economic development program. Dalal also has a three-year, $220,000 grant from the National Science Foundation to support a separate but similar research project.

One of the challenges facing solar cell manufacturers is the fact that most cells are manufactured with crystalline silicon, the same material that’s used to make computer semiconductors. Because computer parts have so much more value than solar cells, Dalal said there’s a shortage of silicon for solar cells.

There is, however, a way to manufacture solar cells using a lot less silicon. Dalal said non-crystalline silicon wafers that are about 2 micrometers thick can replace crystalline wafers that are about 300 micrometers thick. The result is thin solar cells that can absorb lots of light and can be mounted on flexible plastic and other materials. It’s the kind of solar cell technology produced by PowerFilm Inc. But the thin cells produce about half the electricity as crystalline silicon. And their performance drops by about another 15 to 20 percent over time.

“That’s where we come in,” Dalal said.

Iowa State researchers have made discoveries in materials science and plasma chemistry that can improve hydrogen bonding to the silicon in the thin solar cells. And Dalal said that can improve the performance of the cells by about 35 percent and eliminate about 15 percent of the drop in performance.

The discoveries are expected to result in several patents, Dalal said.

They’re also expected to be a potential boost to PowerFilm. Dalal said the new techniques should work with essentially the same manufacturing processes and equipment now used by PowerFilm.

Frank Jeffrey, the chief executive officer of PowerFilm, said he’d be happy to see the performance of his company’s solar cells jump by even 20 percent.

“It would put us in a much stronger competitive position,” Jeffrey said. “If we can increase performance and keep costs in line, that would give us a significant advantage over other people pursuing thin film solar technology right now.”

But he acknowledges Dalal’s project won’t be an easy one.

“It is a significant challenge to get the advancement he’d like to make,” Jeffrey said.

But Dalal is looking forward to facing those challenges in his laboratory.

“This is both challenging and interesting work,” said Dalal, who started studying solar technology in 1972 when he decided he didn’t want to develop smart bomb technology for a defense contractor. “I find it is tremendously interesting, even after 34 years. And it helps humanity instead of killing it, which allows me to sleep at night.”

Source: Iowa State University

Explore further: First of four Fukushima reactors cleared of nuclear fuel

add to favorites email to friend print save as pdf

Related Stories

US seeks China's help after cyberattack

4 hours ago

The United States is asking China for help as it weighs potential responses to a cyberattack against Sony Pictures Entertainment that the U.S. has blamed on North Korea.

Why the Sony hack isn't big news in Japan

21 hours ago

Japan's biggest newspaper, Yomiuri Shimbun, featured a story about Sony Corp. on its website Friday. It wasn't about hacking. It was about the company's struggling tablet business.

Hopes, fears, doubts surround Cuba's oil future

22 hours ago

One of the most prolific oil and gas basins on the planet sits just off Cuba's northwest coast, and the thaw in relations with the United States is giving rise to hopes that Cuba can now get in on the action.

Ancient clay seals may shed light on biblical era

22 hours ago

Impressions from ancient clay seals found at a small site in Israel east of Gaza are signs of government in an area thought to be entirely rural during the 10th century B.C., says Mississippi State University archaeologist ...

Recommended for you

The state of shale

Dec 19, 2014

University of Pittsburgh researchers have shared their findings from three studies related to shale gas in a recent special issue of the journal Energy Technology, edited by Götz Veser, the Nickolas A. DeCecco Professor of Che ...

Website shines light on renewable energy resources

Dec 18, 2014

A team from the University of Arizona and eight southwestern electric utility companies have built a pioneering web portal that provides insight into renewable energy sources and how they contribute to the ...

Better software cuts computer energy use

Dec 18, 2014

An EU research project is developing tools to help software engineers create energy-efficient code, which could reduce electricity consumption at data centres by up to 50% and improve battery life in smart ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.