Speaker 1: Welcome to brain Stuff. Production of I Heart Radio Hey
Speaker 1: brain Stuff Lauren Volga bam here. As human driven climate
Speaker 1: change makes our planet less pleasant to live on, nuclear
Speaker 1: power is getting more attention. A solar and wind energy
Speaker 1: can help cut greenhouse gas emissions too, But if a
Speaker 1: solution can be found to climate change, nuclear power is
Speaker 1: probably going to be part of it. Although nuclear power
Speaker 1: doesn't produce the climate altering gases that create a problem
Speaker 1: with other sources of electricity, it does carry with it
Speaker 1: certain risks for starters. Disposing of radioactive waste from nuclear
Speaker 1: power plants presents a difficult problem, and what to do
Speaker 1: with such dangerous byproducts. Also, what happens if the core
Speaker 1: melts down and creates an environmental catastrophe as happened in Chernobyl, Ukraine.
Speaker 1: In there are other concerns as well, but given our
Speaker 1: current energy predicament, there are enty of reasons to keep
Speaker 1: plugging away and making nuclear power safer. The nuclear reactors
Speaker 1: are run by fission, a nuclear chain reaction in which
Speaker 1: adams split to produce energy, or, in the case of
Speaker 1: nuclear bombs, a massive explosion. For the article this episode
Speaker 1: is based on, has to Fork spoken by email with
Speaker 1: Steve Kron, a professor in the Department of Civil and
Speaker 1: Environmental Engineering at Vanderbilt University. He said approximately four hundred
Speaker 1: and fifty nuclear reactors are an operation worldwide, and they
Speaker 1: all need fuel. He noted that for the most part,
Speaker 1: these reactors operate on uranium two thirty five, and the
Speaker 1: nations that partially recycle the fuel France, Russia, and a
Speaker 1: few other countries combine it with recycled plutonium two thirty
Speaker 1: nine to make what's called mixed oxide fuel. Plutonium is
Speaker 1: a byproduct of used fuel from a nuclear reactor, and
Speaker 1: it's cool that it can help recycle uranium. However, it's
Speaker 1: highly toxic and is the most frequently used material for
Speaker 1: nuclear weapons, which is one reason why scientists have continued
Speaker 1: to explore other options, which brings us to thorium. Thorium
Speaker 1: is an element that was discovered in eight and named
Speaker 1: after Thorpe, the Norse god of thunder, and some scientists
Speaker 1: think that it's the answer to our nuclear power problems.
Speaker 1: Thorium is a slightly radioactive, relatively abundant metal, about as
Speaker 1: abundant as tin and more abundant than uranium. It's also widespread,
Speaker 1: with particular concentrations in India, Turkey, Brazil, the United States,
Speaker 1: and Egypt. But it is important to note that thorium
Speaker 1: isn't a fuel like uranium. The difference is that uranium
Speaker 1: is fissile, meaning that it produces a sustainable chain reaction
Speaker 1: if you can get enough uranium in one spot at
Speaker 1: one time. Thorium, on the other hand, is not fissile.
Speaker 1: It's what scientists call fertile, meaning that if you bombard
Speaker 1: the thorium with neutrons essentially jump started in a reactor
Speaker 1: fueled with material like uranium, it can transmute into a
Speaker 1: uranium isotope uranium two thirty three, which is fissile and
Speaker 1: suitable for creating power. Thorium was used in some of
Speaker 1: the earliest nuclear physics experiments. Marie Curry and Ernest Rutherford
Speaker 1: both worked with it. Uranium and plutonium became more heavily
Speaker 1: associated with nuclear processes during World War Two because they
Speaker 1: provided the clearest path to making bombs for power generation,
Speaker 1: though thorium has some real benefits. Uranium two thirty three
Speaker 1: formed from thorium is a more efficient fuel than uranium
Speaker 1: two thirty five or plutonium, and its reactors may be
Speaker 1: less likely to melt down because they can operate up
Speaker 1: to higher temperatures. In addition, less plutonium is produced during
Speaker 1: reactor operation, and some scientists argue that thorium reactors could
Speaker 1: destroy the tons of dangerous plutonium that have been created
Speaker 1: and stockpiled since the ninth teen fifties. And not only that,
Speaker 1: A fleet of reactors operating on thorium and uranium two
Speaker 1: thirty three is thought by some scientists to be more
Speaker 1: proliferation resistant, since more sophisticated technology is needed to separate
Speaker 1: uranium two thirty three out of the waste products and
Speaker 1: use it to make bombs. There are downsides to thorium, however.
Speaker 1: One is that thorium and uranium two thirty three are
Speaker 1: more dangerously radioactive to chemically process. For that reason, they
Speaker 1: are harder to work with. It's also more difficult to
Speaker 1: manufacture uranium two thirty three fuel rods. Also, as noted earlier,
Speaker 1: thorium is not a fuel. Kron said, if we're going
Speaker 1: to power our planet using a fuel cycle that employs
Speaker 1: thorium and uranium two thirty three, sufficient uranium two thirty
Speaker 1: three must be produced in other types of reactors to
Speaker 1: fuel the initial uranium two thirty three reactors, if that
Speaker 1: can be accomplished. Methods to chemically process thorium two thirty
Speaker 1: two and uranium two thirty three and manufacture fuel from
Speaker 1: them are fairly well established. However, facilities to accomplish these
Speaker 1: processes wouldn't need to be constructed. There are several ways
Speaker 1: thorium could be applied to energy production. Oh One way
Speaker 1: under investigation now is to use solid thorium and uranium
Speaker 1: two thirty two fuel in a conventional water cooled reactor,
Speaker 1: similar to modern uranium based power plants. In fact, more
Speaker 1: than twenty reactors worldwide have been operated with fuel made
Speaker 1: of thorium and uranium two thirty three. Another prospect that
Speaker 1: has been exciting to scientists and nuclear power advocates is
Speaker 1: the molten salt reactor. In these plants, fuel is dissolved
Speaker 1: in liquid salt that also acts as the coolant for
Speaker 1: the reactor. The salt has a high boiling point, so
Speaker 1: they can be more efficient in electricity generation, and even
Speaker 1: huge temperature spikes will not lead to massive reactor accidents,
Speaker 1: such as the disaster that occurred at Fukushima. It might
Speaker 1: sound like this kind of reactor is almost the stuff
Speaker 1: of science fiction, but just such a reactor was operated
Speaker 1: in the United States in the nineteen sixties and is
Speaker 1: currently being built of the Gobi Desert in China. Today's
Speaker 1: episode is based on the article Coldgorian Power the next
Speaker 1: generation of nuclear reactors on how stuff works dot Com,
Speaker 1: written by Jesslin Shields. Brain Stuff is production of I
Speaker 1: Heart Radio in partnership with how stuff works dot Com
Speaker 1: and is produced by Tyler klang Ur. More podcasts from
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