Elusive Solar Paint
Formulas Seek
Funding
BY CHARLES THURSTON
CONTRIBUTING EDITOR
Several researchers around the world have come up
with what they believe could be an inexpensive
solution for solar photovoltaic power: a common
paint formula with embedded particles that will yield a
power flow. While funding to move these projects toward
a commercial phase is tight, it may be secured over the
near term and permit a commercial product in as little
as five years, according to Somenath Mitra, a professor
of chemistry and environmental sciences at New Jersey
Institute of Science, in Newark.
“We have been improving on what we originally developed, and have been talking about funding with several
private investors and institutions, so the technology will
probably be available in the next five to ten years depending on oil prices,” said Mitra. “But that’s a conservative
estimate. The funding could also involve government
investment.”
Going into further detail, Mitra said, “Our technology is to
use organic polymers that release electrons, which are captured by carbon-60 molecules—or Buckyballs. Carbon nan-otubes then act as charge carriers to create a flow of current. These structures could be put into some kind of a bath,
such as titanium dioxide. Thus far we’ve tried using these
structures on polyethylene terepthalate, or PET plastic.
“This is a new technology, so thus far we are only getting about a 1.5-2.0% solar conversion rate, but once we
have more funding, we could alter the chemistry to
improve it,” Mitra continued. “If we could get the rate up
to between five and seven percent—about a quarter of
the rate for traditional silicon devices—that would be
good, because it would be much cheaper to produce than
silicon solar cells.”
Another solar paint research project has been taking
place at Swansea University’s School of Engineering, in
Swansea, Wales, under Professor David Worsley. Their
technology involves bonding light-sensitive dye molecules to titanium dioxide particles, which is applied as a
paste to steel surfaces. The project arose from a study of
steel paint corrosion. It has a reported solar conversion
rate of five percent, and estimates are that it could be
commercially available in as little as two years.
Yet another project involving dye is being developed at
Massachusetts Institute of Technology by Marc Baldo, an
associate professor of engineering and computer science.
His technology involves using organic dye as a coating on
the glass focal point of solar concentrators, in place of mirrors, the current technology. The dyes absorb light energy at
different wavelengths, then transmit it to solar cells at the
edge of the collector.
Other dye-based solar projects have been studied at the
Caltech Center for Sustainable Energy and at the
University of Toronto, among other institutions.
One commercial product, which comes close to solar
paint is an ink-based product being commercialized by
Nanosolar, of San Jose, CA. The company is embedding
semiconductor particles in ink, which is then coated onto
long rolls of aluminum foil and cut into solar panels. The
company suggests it can turn out solar panels at a tenth
of the cost of other thin-film solar panel makers. The
first panels have already been shipped, so performance
data should be forthcoming soon. CW
Somenath Mitra, a professor of chemistry and environmental
sciences at New Jersey Institute of Science, in Newark, NJ is
one of several researchers around the world that is developing
paint with embedded particles to generate solar power.
