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Technologies seeking to surpass the silicon In the desert between Tucson and Yuma,
that has been used in PV to date need to be more these UA ideas are being put to work on a UA experts
efficient at capturing the energy of the sun’s rays, 3-square-mile plot along Interstate 8 near Gila are helping
Norwood adds. While current panels run at 20 Bend. There, a solar farm called Solana contains
percent efficiency, Norwood’s team is trying to thousands of parabolic trough mirrors developed increase the
achieve 30 percent efficiency in research for the by Roger Angel, optical engineer and head of the
Department of Energy’s Micro-scale Optimized UA’s Richard F. Caris Mirror Laboratory. use of solar
Solar-cell Arrays with Integrated Concentration, The mirrors concentrate sunlight onto black
or MOSAIC. collector pipes and superheat the oil inside them, energy through
which can either heat water to make electricity
in a steam turbine or heat molten nitrate salt to
New Ways to Store Solar Power improvements
store the heat for nighttime power production.
A parallel goal to finding ways to store solar The Solana site makes 250 megawatts of
power for use at night is reducing the amount of electricity, enough power for more than 70,000 in photovoltaic
water used while generating electricity. The UA households.
is developing solar collectors that could be the technologies.
answer to both. For Grads, a Bright Job Outlook
“Generating electricity without using water
will be a paradigm breaker, a game-changing UA students involved in all this solar research
step,” says Dominic Gervasio, a researcher in the have strong job prospects after graduation. One
UA’s Department of Chemical and Environmental in 50 new jobs in the U.S. is in the solar industry,
Engineering. Avoiding the use of scarce water and 1,000 new solar jobs are created every week.
supplies is far from trivial; electric power Some Wildcat entrepreneurs have created
generation accounts for 2 percent of all water use their own jobs in solar. Kevin Cook ’93 helped
in Arizona. start Technicians for Sustainability, a Tucson
Gervasio’s approach uses a type of liquid solar company with a staff of 50 today. It has
chloride salt as an alternative to heavy petroleum outfitted 2,000 homes with solar.
for heat transfer. The liquid chloride salt allows Katherine Kent ’94 ’06 launched The Solar
the transfer of large amounts of heat, enough Store in 1998. “I wanted to solve problems and
to energize carbon dioxide to turn turbines and build things,” she says. So far, she has installed
produce electricity — similar to a conventional solar in about 6,000 homes and businesses. And
steam turbine, but without the water. Kent’s father, John Wesley Miller ’55, has built
Transferring sunlight’s energy at high more than 90 solar homes in central Tucson.
temperatures could make the UA research a “Arizona is the best solar state there is,” says
key factor in the next generation of America’s Miller. “It’s affordable right now. Don’t wait.”
electrical generation projects. Molten chloride
salts can operate at temperatures over 750
degrees centigrade, a “magic number” for pushing
a turbine with superheated carbon dioxide, rather
than with steam, Gervasio says.
The hot chloride salt can also store heat
from solar collectors more safely than other
approaches. Gervasio collaborated with Peiwen
Li’s Energy and Fuel Cell Laboratory in the
UA’s Aerospace and Mechanical Engineering
Department to make sure that the pipes carrying
the heated liquids could handle the molten salts.

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