Cons of Thorium Reactors Shouldn't Stop Future Development

Before we get to the conclusion, here are some more pros of thorium reactors (continued from Part Two):

There is 10 times more thorium available in the world than uranium. The world could actually run out of naturally occurring uranium in 80 years, but thorium is said to be so abundant it could last thousands of years.

A thorium reactor could consume fissile materials from old uranium reactors and clean it up. Thorium reactors produce a tiny fraction of the radioactive waste that conventional uranium reactors produce, and their operation on a wide scale would reduce the sum of waste material in storage over time.

So far so good — but the obvious question is why haven’t these wonder reactors been brought to commercial reality?

Read the press in favor of them, and you would assume it’s all down to the twin impact of a Cold War-type need for plutonium, which arose as a by-product of uranium reactors and the lobbying power of entrenched uranium reactor manufacturers.

It’s probably not as simple as that, but it is true to say any technology needs substantial amounts of funding if the technological challenges are to be overcome.

But a list of the disadvantages in a Wikipedia article about Molten Salt Reactors such as these hardly seems to suggest major technological breakthroughs are required.

Absent is a suggestion that the process is unstable, fundamentally inefficient or (on a per-plant basis) excessively expensive. Indeed, the Shanghai team plans to build a tiny 2-MW plant using liquid fluoride fuel by the end of the decade, before scaling up to a commercially viable size over the 2020s, by which time we can only hope a more entrepreneurial economy may have fast-tracked the funding and skills to already have a commercially viable option.

Either way, thorium may be more of a household name in the future than it has been in the past.


  • I am terrifically happy to see this topic being covered in a trade magazine site. People whom I’ve told about thorium reactors look at me like I am talking about magic wands and fairy dust. When a new technology starts getting covered in industry rags, well, folks it is real.

    The article is right that the Wikipedia article’s “cons” need “technological breakthroughs.” All of the problems are straightforward engineering and materials selection. It may not be an exaggeration to say that your local engineering consulting office could probably work most or all of them out. I know I have worked for some who would be tickled pink to work on such projects.

    The materials problems have to do with the gamma radiation being particularly hard on piping. But you know what? If a pipe lasts only 3 or 6 months instead of 10 years, who cares? Preventive Maintenance (PM) programs in industry deal with such necessary replacements all the time. The cost of doing that? Compared to a $30 billion old-style nuclear plant? Are you kidding? And I guarantee that today’s nuclear plants have similar PM programs, so this is a non-issue, when you come down to it. And when you can shut the reactor down in an hour or so by turning the switch, as opposed to days and weeks currently, such maintenance should be a breeze.

    I DO find it mildly amusing that Jiang has already 140 PhDs working on this. It would probably be more suitable and efficient to have 140 design engineers, electrical engineers, piping designers, and mechanical designers, since 95% of the projects are beneath the PhDs – the everyday engineering tasks of drawing up systems, assemblies and parts.

    I don’t mind the overkill – especially if it can persuade Western governments that they need to get into this seriously – and NOW. Otherwise we will all be at the mercy of the Chinese manufacturers for several or many decades to come.

    But this technology – literally a known technology that has been sitting on the shelf for half a century – WILL come to pass, and it will be a boon to all of humanity, no matter who has the patents on it. It has the promise of being the “free energy” we were promised back in the 1950s. And paying the Chinese or paying Westinghouse – what’s the difference?

    And if LFTR reactors can burn up the nuclear wastes of 60 years of nuclear energy – and produce energy FROM those wastes, CLEANLY – only vested interests could be against it.

    I also love the promise that plants can be sized up or down like it was mentioned, even to the point of small communities and large companies having their small own thorium plants. Just think of not only not having monstrosities like wind turbines, but also no high power lines and towers, a blight on the landscape as well. Environmentalists should be jumping on this with all four feet.

    There is so much upside to this. Thanks for pointing out that the downside is so insignificant.

  • in 1962 clarkston collage in new york had a test reactor on campus i was told as a visitor it was shut down at the end of the day . it was in a room and appeared no bigger than a large chest the time i had no idea the implications of what i had just viewed

  • It’s rather hard to take this kind of post seriously when the very first “pro” is utter nonsense.

    Uranium is not going to run out in 80 years. This statement alone tells me that the author has no understanding of the issues whatsoever.

    Thorium is exactly equivalent to Uranium-238. They both require “breeder” reactors (that’s what Thorium reactors are…breeders).

    We have millions of tons of Uranium-238 sitting around in government warehouses, leftover from separation processing. We have trillions of tons in mines. U-238 is massively abundant and if we used it (in a breeder reactor) we have enough in stock, in warehouses, to power the world for 1000 years.

    U-235 is the only type of Uranium that is in short supply.

    These kinds of mistakes are what make the Thorium “advocacy” movement so unbelievable.

    • According to this chart, Thorium is slightly more abundant even than U-238:

      We do also have plenty of Thorium sitting around – that needs no processing at all to use in LFTRs.

      You may have a point about U-238 being able to be used in a breeder reactor. But a couple of questions:

      1. What is the process of turning U-238 into a usable fuel?

      2. What isotope of what element becomes the actual core fuel?

      3. It is my understanding that U-238 is NOT a good fuel itself, so can you point me at some source saying it can be changed into (bred) some other isotope?

      4. If U-238 CAN be used as a breeder fuel, how many neutrons are given off? If it is not over 2.0, it isn’t useful. Do you know how many?

  • The use of U-238 is totally analogous to Thorium (which consists of of Th-232). Th-232 is irradiated to create U-233 that can be used as fuel whereas u-238 is irradiated to create Pu-239 that can be used as fuel. Neither Th-232 or U-238 are useful as fuel themselves because they have a relatively low probability of fissioning when capturing a neutron. The primary difference is that U-233 can produce enough excess neutrons to breed with slow (thermal) or fast neutrons where as Pu-239 requires fast neutrons.


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