SOLAR TODAY - May 2011 - Innovative Design

HennessyProductions.com
With a $4.8 million award from the SunShot Initiative,
Gloucester, Mass.-based Varian Semiconductor
is developing a tool that manufactures
interdigitated back-contact solar cells with ionimplanting
technology. Featured above is a closeup
of the tool.
Researchers at PPG Industries prepare glass samples for accelerated exposure testing for a new encapsulant
for cadmium telluride (CdTe) thin-film solar modules. The end product will combine transparent
conducting oxide glass substrate with an anti-reflective coating.
ppg industries
roots in the 19th century. PPG’s contribution to
solar actually predates the industry: Back in the
1930s, the company pioneered the first low-iron
glass. Now, backed by $3.1 million in SunShot
funding, PPG is working to perfect a glass encapsulant
for modules made with cadmium telluride
(CdTe) — the most advanced thin-film technology
in mass production.
PPG will try to maximize CdTe module efficiency
by pulling three innovations onto their
high-transmission glass. “About 4.5 percent of
the sun’s energy is lost on the outside of the
module,” says Jim McCamy, PPG’s manager
of solar technology. “By reducing losses from
reflectivity, we’re increasing the number of watts.
By creating better conductive layers, we improve
the number of watts.”
The new encapsulants, still unnamed, will
separate the first layer of CdTe from the underlying
transparent conducting oxide (TCO) glass
substrate with a buffer layer. A third component,
an anti-reflective coating, will be applied to the
module front side over the TCO glass. “These
Mike Koshmrl (mkoshmrl@solartoday.org) is SOLAR
TODAY’s associate editor.
At 1366 Technologies, Frank van Mierlo, right, and fellow co-founder Emanuel Sachs, middle, are working
to commercialize their Direct Wafer silicon wafer manufacturing process. By pulling wafers directly from
the silicon melt, the technology halves the need for hyper-pure silicon. At left is Carmichael Roberts,
chairman of the 1366 Technologies Board.
1366 Technologies
Copyright © 2011 by the American Solar Energy Society Inc. All rights reserved.
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