On Earth Day, scientists have announced a collaboration to develop an affordable
photovoltaic system capable of concentrating solar radiation 2,000 times and
converting 80 percent of the incoming radiation into useful energy. The system
can also provide desalinated water and cool air in sunny, remote locations
where they are often in short supply.
A three-year, $2.4 million grant from the Swiss Commission for Technology
and Innovation has been awarded to scientists at IBM Research, Airlight Energy,
ETH Zurich and Interstate University of Applied Sciences Buchs NTB to research
and develop an economical High Concentration Photo Voltaic Thermal (HCPVT)
system.
Based on a study by the European Solar Thermal Electricity Association and
Greenpeace International, technically, it would only take two percent of the
solar energy from the Sahara Desert to supply the world’s electricity needs.
Unfortunately, current solar technologies on the market today are too expensive
and slow to produce, require rare Earth minerals and lack the efficiency to
make such massive installations practical.
“The design of the system is elegantly simple,” said Andrea Pedretti , chief
technology officer at Airlight Energy. “We replace expensive steel and glass
with low cost concrete and simple pressurized metalized foils. The small
high-tech components, in particular the microchannel coolers and the molds, can
be manufactured in Switzerland with the remaining construction and assembly
done in the region of the installation. This leads to a win-win situation where
the system is cost competitive and jobs are created in both regions.”
According to Bruno Michel, manager, advanced thermal packaging at IBM
Research, the group intends to use triple-junction photovoltaic cells on a
micro-channel cooled module which can directly convert more than 30 percent of
collected solar radiation into electrical energy and allow for the efficient
recovery of an additional 50 percent waste heat.
“We can achieve this with a practical design made of lightweight and high
strength concrete, which is used in bridges, and primary optics composed of
inexpensive pneumatic mirrors—it’s frugal innovation, but builds on decades of
experience in microtechnology,” added Michel.
With such a high concentration and a radically low cost design scientists
believe they can achieve a cost per aperture area below $250 per square meter,
which is three times lower than comparable systems. The levelized cost of
energy will be less than 10 cents per kilowatt hour (KWh). For comparison, feed
in tariffs for electrical energy in Germany are currently still larger than 25
cents per KWh and production cost at coal power stations are around 5-10 cents
per KWh.
Scientists envision the HCPVT system providing sustainable energy and
potable water to locations around the world including southern Europe, Africa,
Arabic peninsula, the southwestern part of the United States, South America,
and Australia. Remote tourism locations are also an interesting market. A
prototype of the HCPVT system is currently being tested at IBM Research – Zurich.
