One bellwether project to watch as a gauge
of President-Elect Barack Obama's energy policy will be funding for a
commercial demonstration project at the Idaho National Laboratory to produce
hydrogen and heat with high-temperature, helium-cooled nuclear power.
The project faces technical and finding hurdles and is already
running behind schedule. "The Department of Energy asked us to complete the
plant by 2016, but we are revising the date to 2021," said Sten A. Caspersson
Jr. of Westinghouse in an interview with Design News following a presentation
at the annual Congress of the American Society of Mechanical Engineers in Boston, MA. Caspersson is
project manager of next-generation, high-temperature reactors at Westinghouse,
a Pennsylvania
company owned primarily by Toshiba.
The Energy Policy Act of 2005 authorized the Department of
Energy to develop a research and development program that could deliver a high-temperature gas-cooled reactor prototype to increase domestic energy supplies,
reduce greenhouse gas emissions, and move more quickly towards a national
hydrogen economy. Westinghouse and its partners plan to build a pebble bed
modular reactor that uses fuel balls surrounded by a hollow sphere of
graphite moderator. These are stacked in a close-packed lattice and are cooled
by helium, not water. The term "pebble
bed" derives from the use of spheres. Rods are used to control fission in
conventional nuclear reactors.
Output of the reactor will be hydrogen that could serve as a
fuel for vehicles and heat that could be used to more effectively produce fuels
from oil sands or coal. Caspersson damped excessive enthusiasm for hydrogen as
a quick-fix to high gas prices. "In his 2005 State of the Union address,
President Bush said our grandchildren will be driving hydrogen-fueled cars.
We're not even close to that." President
Bush referenced hydrogen-fueled cars in his 2005
and 2006 State of
the Union addresses.
Several challenges are delaying development of the Idaho demonstration
project:
Licensing. Will
federal authorities look favorably on the technology? President-Elect Barack Obama
says he will support nuclear power if safety issues are adequately addressed.
Caspersson told Design News: "Light water reactors are very safe. These (next
generation nuclear plants) are even safer." For example, he said it would be
almost impossible to extract fissionable materials from spent fuel balls. In
addition, the spent balls could be safely stored in a remote location, such as
the Yucca Mountain
site in Nevada
proposed for nuclear waste.
Economics: The
cost to build a plant is currently estimated at $2.4 billion. Congress
authorized the DOE to spend $1.25 billion on the project through 2013. However,
funding has been steady around $30 million each year. The National Academy of
Sciences has already reported
that the project is under funded. A Westinghouse projection based on revenues
from sale of hydrogen and heat, and coupled with a credit for improved carbon
footprint, show the economics to be "marginally acceptable", in Caspersson's
words. One big test will be the willingness of a company such as Dow or Chevron
to step forward and embrace the concept as a commercial project.
Technology. There
are many issues. One is the need for development of a material to be used in a
lynchpin of the concept: an intermediate heat exchanger. Existing materials
don't meet the requirements for intense heat and pressure. "We're starting with
a material we know something about, 800H," said Cappersson. 800H is a
controlled carbon Inconel alloy that receives a high temperature annealing
treatment to produces an average grain size of ASTM 5 or coarser. Materials
that possess even greater creep and rupture strength are being developed by
national labs, Caspersson told Design News. "We will replace 800H with an
improved metal or ceramic when they become available," he said. One potential
replacement is an alloy called 617, which contains nickel, chromium, cobalt,
and molybdenum. Materials development "is one of the primary barriers to
success of the project," Caaspersson said.
Another technical challenge is the requirement to improve the purity of
hydrogen that will be produced
Even one of the environmental underpinnings of the project
was challenged at the ASME Congress by Lawrence L. Kazmerski, director of the
National Center for Photovoltaics in Golden, CO. In a question-and-answer
period following Caspersson's presentation, Kasmerski questioned why one of the
project's goals is production of heat that could be used to more economically
produce hydrocarbons from oil sands in Canada. Another potential use for
the heat is to produce gas from coal. The
fossil fuels, when burned, release carbon dioxide. Caspersson responded that
the nation's energy mix will still require use of fossil fuels. In a discussion
following the presentation, Caspersson conceded that a South African project to convert gas to fuel is
a huge producer of carbon dioxide emissions. Kazmerski was also a speaker at
the National Science Foundation-sponsored forum at the ASME Congress.
Meanwhile, production of a peddle-bed nuclear reactor is already
under way in South Africa,
and China
is aggressively developing
the technology.
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