[ExI] Are mini nuclear power stations the way forward?

[Eugen Leitl]

On Thu, Mar 17, 2011 at 08:50:01AM +0100, Eugen Leitl wrote: > On Wed, Mar
16, 2011 at 11:05:23PM -0400, Mike Dougherty wrote:

In the same thread:

http://www.scientificamerican.com/article.cfm?id=sunshot-lowering-price-of-solar-electricity

SunShot: Lowering the Price of Electricity from the Sun

The U.S. Department of Energy aims to make electricity from the sun cheaper
than that from burning coal or natural gas

By David Biello  | Monday, March 14, 2011 | 15

solar-PV-installation HERE COMES THE SUN: The U.S. Department of Energy aims
to make electricity from the sun as cheap as that from burning coal or
natural gas--by 2017. Image: Dennis Schroeder, NREL Staff Photographer

NATIONAL HARBOR, Md.—Silicon translates sunshine into electricity—and Earth
receives enough sunshine in a daylight hour to supply all of humanity's
energy needs for a year. But despite being as common as sand, photovoltaic
panels made from silicon—or any of a host of other semiconducting
materials—are not cheap, especially when compared with the cost of
electricity produced by burning coal or natural gas. The U.S. Department of
Energy (DoE) aims to change that by bringing down the cost of solar
electricity via a new program dubbed "SunShot," an homage to President John
Kennedy's "moon shot" pledge in 1961.

"If you can get solar electricity down at [$1 per watt], and it scales
without subsidies, gosh, I think that's pretty good for the climate," notes
Arun Majumdar, director of the Advanced Research Projects Agency–Energy
(ARPA–e), the DoE's high-risk research effort. "With SunShot, the goal is to
reduce the cost of solar to [$1 per watt] in the next six years."

As it stands, melting silicon or depositing thin layers of copper indium
gallium selenide, then manufacturing photovoltaic modules and installing them
on rooftops or in large arrays in the desert, can cost as much as $10 per
watt. And whereas some technologies can deliver modules for roughly $1 per
watt, installation at least doubles that.

"We are making solar for the masses…to get to [a] cost point that is viable,"
said Bruce Sohn, president of Columbus, Ohio–based First Solar, the world's
largest thin-film photovoltaic manufacturer, which claims it can produce its
modules for less than $1 per watt, on a panel at ARPA–e's second annual
summit on March 1. "We are looking to make something that can compete head to
head with fossil fuels over the long term."

As part of the new SunShot initiative, DoE committed some $27 million to fund
novel methods for producing solar cells and their components—like 1366
Technology's effort to grow pure silicon wafers directly rather than hewing
them from long ingots of the material or Solexant's effort to build thin-film
solar cells from semiconducting materials that are neither toxic nor rare.
The goal is to produce solar modules at roughly 50 cents per watt with
attendant hardware and installation costing the same amount. To reach that
target the photovoltaic cells will have to convert at least 20 percent of the
sunlight that shines on it into electricity and cost only 25 cents per watt
by 2017. "The future of the U.S. depends on three securities: national,
economic and environmental. The foundation of all of this is innovations in
energy technology," Majumdar said in his own speech to the summit. "The
future is still up for grabs. How do we win the future? Invent affordable
clean technology. Make them locally, sell them globally."

Of course, harvesting the sun's power is not limited to photovoltaic panels.
The DoE push also will incorporate efforts to create solar-thermal power
plants that can store the heat of the sun for 12 to 17 hours by 2020, along
with attempting to address some of the issues surrounding permitting,
inspection and connection of solar systems to the electricity grid. "We want
change, we want innovation, we want to overthrow the old energy order," said
former California governor Arnold Schwarzenegger in a summit keynote address.
"We want a new era of energy and a new era of American competitiveness."

Already, electricity from the sun costs roughly the same as that generated
from burning fossil fuels in places like Hawaii, which remains the only state
to rely on imported oil for the bulk of its power. And solar power represents
the fastest-growing sector of electricity generation. U.S. solar production
in 2010 increased by nearly one gigawatt (billion watts), although that
represents roughly the amount of electricity one nuclear power plant can
produce. But even at that pace of adoption—spurred by both federal and state
government largesse—solar still produces less than 1 percent of all U.S.
electricity. And in 2035, by which time the DoE's Energy Information
Administration (EIA) predicts that solar will have grown fastest among all
energy resources (increasing sevenfold), all renewables put together, solar
included, will only provide 14 percent of U.S. electricity.

The EIA has often been wrong in such long-term forecasts, but competing with
natural gas—newly cheap thanks to the vast resources tapped by fracking in
the eastern U.S.'s Marcellus Shale Formation—may prove difficult, even with
SunShot. "Natural gas has low capital cost, higher fuel cost but overall
lowest costs," noted EIA Administrator Richard Newell at the ARPA–e
conference. "There are significantly higher costs for other power sources."

Yet, even at a higher price, solar can offer benefits, which is why Duke
Energy has invested $50 million putting solar arrays on the roofs of grocery
stores and some of its other large customers. "Distributed solar can be
thought of as a distributed resource, a multiple value resource," Duke Chief
Technology Officer David Mohler told ARPA–e attendees. "The proper comparison
for that is not the cost of a bulk power system, it's the cost and benefit of
having an embedded resource."

And flexible solar cells in sheets have already found novel applications
powering the telecommunications and other electronic equipment of U.S. Marine
units deployed in Afghanistan. Small-scale solar is also booming in places
such as Kenya that do not have an electricity grid for charging cell phones
or batteries that power lights at night. "We will need every energy resource
we can lay our hands on," said Kurt Yeager, executive director of the Galvin
Electricity Initiative, an effort to develop the smart grid in the U.S.
"There are two billion people in the world without access to electricity.
Security means giving them energy."

Of course, the DoE has already invested some $1 billion in solar energy
research since the turn of the century, funding efforts to develop "black"
silicon or cells employing quantum dots. "If renewables are cost-competitive
with fossil fuels then it's a very, very different world," Secretary of
Energy Steven Chu said at the ARPA–e summit.

Yet, despite inventing the technology in the 1950s and more than 30 years of
government support, the U.S. share of the global market for photovoltaic
modules is down from more than 40 percent in 1995 to just 6 percent in 2011.
China's Jiangsu Province alone—home to Suntech Power, the world's largest
maker of photovoltaic panels—has begun investing more than $152 million a
year in solar technology since 2009.

"Just because we lost the lead doesn't mean we can't get it back," Chu said.
"We still have the opportunity to lead the world in clean energy…but time is
running out."