Nuclear Energy Accidents May Become Thing of Past

When it comes to nuclear power, there’s talk of all sorts of
technologies and fuels — things that could make the average guy’s head
spin. But if you think nuclear energy is an efficient and pollution-free
way to make electricity, consider “thorium” and “molten salt reactors.”
Huh? On the periodic tables, thorium

rests just two spots away from uranium, which is the prevailing fuel
used by today’s nuclear reactors. Once uranium is used as a fuel, it
becomes highly radioactive. That waste is then cooled in spent fuel
pools before is stored in above-ground, concrete-encased steel caskets.
As the world learned from Japan’s Fukushima nuclear accident, that radioactive material could escape and do a lot of potential harm.

Thorium, on the other hand, can also be used to generate nuclear energy.
But its proponents are saying that “molten salt reactors” that burn
such fuels won’t “meltdown” because, unlike today’s high-pressured
units, they are low-pressured and won’t vaporize.

“Thorium is the most abundant nuclear material on earth,” says Clinton Bastin, who was with the U.S. Atomic Energy Commission and the U.S. Department of Energy from 1955 until 1997. “It
should eventually be used in nuclear reactors because it is so
plentiful. But it should not be used now because it introduces the
problem of highly radioactive material that is very difficult to deal
with.”

Bastin, who is also a former VP of the World Council of Nuclear
Workers, explained to this reporter that there are demonstration
projects now occurring involving thorium. Active trials are taking place
in China and India, and to some extent in Canada. But no country is
using a significant amount of thorium to produce electricity, much less
in molten salt reactors.

Thorium is abundant in nature, with about four times the amount in
the earth’s crust than uranium. When used as a nuclear fuel, the whole
cycle produces less radioactive waste than does uranium. But, the
thorium fuel cycle still makes radioactive material that must be
warehoused and some say it does produce an isotope of uranium that could
be used in nuclear weapons, although plutonium that is the preferred
method is not a byproduct.

Why has this country chosen uranium over thorium? The decision was
made in the 1950s during the emergence of nuclear power generation. That
was during the Cold War and the U.S. government had decided that the
national treasury would be invested in uranium fuels, as they can be
more easily enriched to make nuclear bombs.

Today, the U.S. might have chosen a different path. But it would be
too costly to retrofit the existing nuclear energy infrastructure to
comport with the thorium fuel cycle. The supply chain is now fully
stocked and includes everything from uranium suppliers to reactor
designers.

“It is possible to convert the existing reactors to thorium reactors
over time,” says Thomas Drolet, a nuclear energy expert with his own
consulting firm in Englewood, Fla., in a phone interview. “But it would
be high capital costs. What you really want to do is to start from
scratch.”

The 104 nuclear power plants operating
in the United States today use so-called second generation light water,
solid fuel reactors. They operate, on average, at more than 90 percent
capacity and have been working safely for at least 36 years.
“Third generation” light water reactors are going up predominately in
India and China and they are the ones that are to be constructed by Southern Company and Scana,
both of which were recently approved to build by the U.S. Nuclear
Regulatory Commission. Those third generation reactors have superior
fuel technology, thermal efficiency and safety features.
The next-generation reactors, called “fourth generation,” are those
that run at much higher temperatures. They are even more efficient than
those in the third generation, giving them the potential to produce more
electricity at less cost. The high temperatures also enable hydrogen
production as well as a variety of industrial applications.
Thorium is most suited to run in fourth generation “liquid fuel”
reactors, which operate at lower pressures and which are therefore
safer. Such molten salt reactors must reach high level temperatures to
melt a salt solid. That liquid and fuel mixture is then used as a
coolant in the fuel cycle. Critics say that it is still difficult to
maintain high thermal efficiencies, which diminishes the economic case
for those liquid fuel reactor’s over today’s technologies.
“All fourth generation reactors make much less waste and run at
higher temperatures,” says John Kutsch, executive director of the Thorium Energy Alliance in Chicago,
who spoke with this writer by phone. “But the similarity ends there.
Inherently, thorium is much more abundant and easier to handle.”
China, he adds, is likely to get there first. It is demonstrating a
modern thorium reactor and it could have one in full-scale production by
2020. China is about 70 percent of the way to commercialization, he
notes, emphasizing that the United States invented the technology and
could leapfrog that nation.
What’s stopping this country? Beyond the established interests that
have already invested huge sums in the current technologies, there are
questions about the creation of huge piles of thorium — something that
would come with immense regulatory oversight and the associated
expenses.
As such, Kutsch is saying that the industry would be willing to
manage a centralized “rare earth” refinery that would safeguard or find
uses for the thorium that has been stockpiled. His group would also like
the U.S. Nuclear Regulatory Commission to write the rules and
regulations for liquid reactors that use the thorium fuel cycles.
The reality is that solid fuel reactors using uranium are now
supplying 20 percent of this country’s electric generation. Liquid fuel
reactors, or molten salt reactors, that use thorium will not replace
them. But the thorium technology still has place in the mix, as
evidenced by the international research now occurring. China is furthest
along and if it succeeds, the science will be applied elsewhere.