Department of Energy last week announced $2.7M USD in American
Recovery and Reinvestment Act Funding (ARRA) for three ANL solar
projects. An additional $5M USD in ARRA Funding was awarded
jointly to ANL, Commonwealth Edison Co., GridPoint and the University
of Illinois Sustainable Technology Center (ISTC).
project will invest $945,000 in developing transparent thin films for
solar cells. Project leader Dr. Jeffrey W. Elam, a chemist with
ANL's Energy Systems Division, writes that this project will look
into both "transparent conducting oxides using indium (ITO)"
and "TCO films with little or no indium". The TCO
films seem particularly promising, as they reduce the reliance on
scarce metal. The indium free films are deposited on zinc
oxide or tin oxide, and many of them are being custom-developed for
While there's typically a gap before such
materials hit the market, improving efficiencies of commercial
designs, Dr. Elam sees that gap as relatively short for these films.
He states, "In two of our current solar cell projects, we have
fabricated prototype devices and we are engaged in 3-year projects to
scale these up and demonstrate manufacturability. These solar cells
should be ready for commercialization in 3 years."
second project, led by chemist Alex Martinson, has received $750,000
in funding to develop high-efficiency thin films via unconventional
materials and woven films. We inquired about the
significance of weaving the films. Martinson replied, "The
'weaving' may allow the incorporation of affordable materials with
modest electrical properties into photovoltaics with good light
harvesting efficiency. The advantage is that the requirement for
active layers with both superior optical and superior electrical
properties is relaxed."
As to what unconventional
materials will be explored, he states, "Some of the atypical
active layers being considered include copper sulfide (Cu2S), iron
oxide (Fe2O3) and pyrite (FeS2)."
A third project led by
ANL materials scientist Dileep Singh has received $1M USD to explore
fluids to store thermal solar power and to more efficiently transfer
solar thermal energy during the day at concentrated-thermal
solar power plants. Improving storage will help reduce the
inconsistency of solar power availability, while improving energy
transfer will significant lower the cost of solar power, bringing it
closer to power from fossil fuel sources.
"There is a disparity in the levelized cost of energy (LCOE)
between solar and fossil fuel, etc., which prohibits the widespread
use of solar energy. To reduce this disparity, in concentrated solar
plants, we are considering two approaches: storage of solar energy so
that power plant can be operational during night time or cloudy days
and more efficient transfer of thermal energy from heat transfer
fluids (that are heated by mirrors) to steam in the heat exchanger.
For instance, if thermal properties of the heat transfer fluids are
enhanced then the inlet temperature into the turbine can be
increased. For every 10°C increase in the inlet temperature
of turbine, the LCOE for solar will be reduced by $9 per MWh.
With current difference between solar and combined cycle natural gas
power plant being $44 per MWh, it will make a significant
impact. This does not include the cost reductions from energy storage
aspects. DOE’s goal is to increase storage capability up to 6 hours
by 2015 and 16 h by 2020."
Finally, the bulk of the money
will go to a joint experimental deployment of solar power by ComEd,
GridPoint, and ISTC to approximately 200 customers' homes.
These homes will receive smart
meters, as will other homes without solar power. Some of
the solar households will also receive a battery backup system, which
will provide 10 kWh energy storage at 4.9 kW of power.
study will run 12 months and will look at how the smart meters affect
customer's usage, and additionally how much energy saving the solar
and solar+battery backup installations yield, respectively.
would like to thank Argonne National Laboratory's employees for their
help with this article.