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Reason...
Nuclear Disaster in
Japan
Does it show a way forward for nuclear power?
By Ronald Bailey
March 15, 2011
The crisis at Japan’s Fukushima Daiichi nuclear power plants continues.
Amazingly, a 40-year-old power plant built to withstand a 7.9 magnitude
earthquake on the Richter scale shut down automatically as designed
when the Earth began shaking. In fact, it stood up to an earthquake
that released more than 40 times the amount of energy the plant was
designed to survive. At the moment it appears that the 33-foot tsunami
that knocked out its backup diesel generators for its coolant pumps was
the plant’sundoing.
Two earlier explosions were hampering attempts to keep the reactor
cores inundated with seawater, and a third explosion yesterday may have
uncovered some of the spent fuel rods in a cooling pond at one of the
facilities. The explosions appear to be caused by a buildup of highly
volatile hydrogen gas within the facilities. After this latest
explosion, radiation levels increased outside the facilities and
residents within a 12-mile radius of the stricken plants have been
evacuated and those living within 19 miles have been advised to stay
indoors.
Reports are spotty, but exposure to radiation just outside the plant
for one hour reached the equivalent of more than three years of
naturally occurring radioactivity. Despite multiple setbacks, plant
workers continue their heroic efforts to cool down the reactor cores.
As I write, most experts believe that the plant woes will not produce
major health or environmental consequences, although the clean up will
cost Tokyo Electric billions.
Naturally, anti-nuclear activists and some policy makers around the
world are citing the disaster as evidence that nuclear power is
inherently unsafe and should be banned. For example, in Germany
thousands of anti-nuclear protesters flooded the streets of Berlin
shouting “turn them off.” In response, German Chancellor Angela Merkel
ordered that the country’s seven nuclear power plants built before 1980
be shut down for a safety review. In the United States, Sen. Joe
Lieberman (I-Conn.) and Rep. Edward Markey (D-Mass.) urged a moratorium
on building new nuclear power plants.
Could it happen here? Although earthquakes can and do occur all over
the United States, the West Coast and Alaska are the most seismically
active regions. The facilities whose physical locations most closely
resemble that of the Fukushima plants are two nuclear generating plants
built on the coast of California, the Diablo Canyon Power Plant and the
San Onofre Nuclear Generating Station. The two reactors at the Diablo
Canyon began operation in the mid-1980s and are built to withstand
7.5-magnitude earthquakes on the Richter scale. The reactors are
located 85 feet above the coast. A recent analysis downgraded the most
likely earthquake in the area to about half that.
The two reactors at San Onofre began operations in 1968 and are built
to withstand a magnitude 7.0 earthquake. Seismic analysis indicates
that the largest likely earthquake near that facility would register a
6.5 magnitude. The San Onofre reactors are enclosed by a 30-foot high
tsunami wall. It should be noted that nearby Newport Beach experienced
a 12-meter tsunami surge (39 feet) in 1934. The Sendai surge may have
been about 33 feet in height.
The Cascadia subduction zone off the coast of Washington, Oregon, and
Northern California is the region most likely to experience an
earthquake equivalent to the Sendai one. In January 1700 a magnitude
9.0 megathrust earthquake occurred sending tsunami waves across the
Pacific to Japan and reached as much as eight meters above sea level
(26 feet) onshore in the Pacific Northwest. Fortunately, the closest
nuclear power plant, the Columbia Generating Station, is located 200
miles inland.
Back in 1980 during the “energy crisis,” the National Research Council
issued a report, Energy in Transition, 1985-2010, in which one scenario
suggested that the U.S. might be fueled by as many as 1,000 nuclear
power plants by 2010. But the 1979 Three Mile Island accident boosted
public opposition to nuclear energy. The good news was that that
partial reactor meltdown had essentially no health consequences other
than anxiety. Nevertheless, no new reactors were ordered in the United
States until recently. Despite the Japanese situation, the Obama
administration is insisting that it plans to go ahead with its policy
of subsidizing new nuclear facilities with federal loan guarantees.
Frankly, it is a real question if the private utilities would choose to
build the current versions of nuclear plants without federal loan
guarantees and the backstop of federal disaster insurance.
One hopeful possibility is that the Japanese crisis will spark the
development and deployment of new and even safer nuclear power plants.
Already, the Westinghouse division of Toshiba has developed and sold
its passively safe AP1000 pressurized water reactor. The reactor is
designed with safety systems that would cool down the reactor after an
accident without the need for human intervention and operate using
natural forces like gravity instead of relying on diesel generators and
electric pumps. Until the recent events in Japan, the Nuclear
Regulatory Commission was expected to give final approval to the design
by this fall despite opposition by some anti-nuclear groups.
One innovative approach to using nuclear energy to produce electricity
safely is to develop thorium reactors. Thorium is a naturally occurring
radioactive element, which, unlike certain isotopes of uranium, cannot
sustain a nuclear chain reaction. However, thorium can be doped with
enough uranium or plutonium to sustain such a reaction. Liquid fluoride
thorium reactors (LFTR) have a lot to recommend them with regard to
safety. Fueled by a molten mixture of thorium and uranium dissolved in
fluoride salts of lithium and beryllium at atmospheric pressure, LFTRs
cannot melt down (strictly speaking the fuel is already melted).
Because LFTRs operate at atmospheric pressure, they are less likely
than conventional pressurized reactors to spew radioactive elements if
an accident occurs. In addition, an increase in operating temperature
slows down the nuclear chain reaction, inherently stabilizing the
reactor. And LFTRs are designed with a salt plug at the bottom that
melts if reactor temperatures somehow do rise too high, draining
reactor fluid into a containment vessel where it essentially freezes.
It is estimated that 83 percent of LFTR waste products are safe within
10 years, while the remainder needs to be stored for 300 years. Another
advantage is that LFTRs can use plutonium and nuclear waste as fuel,
transmuting them into much less radioactive and harmful elements, thus
eliminating the need for waste storage lasting up to 10,000 years. No
commercial thorium reactors currently exist, although China announced a
project earlier this year that aims to develop such reactors.
The main problem with energy supply systems is that for the last 100
years, governments have insisted on meddling with them, using
subsidies, setting rates, and picking technologies. Consequently,
entrepreneurs, consumers, and especially policymakers have no idea
which power supply technologies actually provide the best balance
between cost-effectiveness and safety. In any case, let’s hope that the
current nuclear disaster will not substantially add to the terrible
woes the Japanese must bear as a result of nature’s fickle cruelty.
Science Correspondent Ronald Bailey is author of Liberation Biology:
The Scientific and Moral Case for the Biotech Revolution (Prometheus
Books).
Read it with links at Reason
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