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Fusion and Fission/LFTR: Let's Do Both, Smartly

TheRealHocusLocus writes: Disaster preppers have a saying, "two is one and one is none," which might also apply to 24x7 base load energy sources that could sustain us beyond the age of fossil fuel. I too was happy to see Skunkworks' Feb 2013 announcement and the recent "we're still making progress" reminder. I was moved by the reaction on Slashdot: a groundswell of "Finally!" and "We're saved!" However, fusion doesn't need to be the only solution, and it's not entirely without drawbacks.

All nuclear reactors will generate waste via activation as the materials of which they are constructed erode and become unstable under high neutron flux. I'm not pointing this out because I think it's a big deal — a few fusion advocates disingenuously tend to sell the process as if it were "100% clean." A low volume of non-recyclable waste from fusion reactors that is walk-away safe in ~100 years is doable. Let's do it. And likewise, the best comparable waste profile for fission is a two-fluid LFTR, a low volume of waste that is walk-away safe in ~300 years. Let's do it.

Why pursue both, with at least the same level of urgency? Because both could carry us indefinitely. LFTR is less complicated in theory and practice. It is closer to market. There is plenty of cross-over: LFTR's materials challenges and heat engine interface — and the necessity for waste management — are the same as they will be for commercial-scale fusion reactors. To get up to speed please see the 2006 fusion lecture by Dr. Robert Bussard on the Wiffle ball 6 plasma containment, likely the precursor to the Skunkworks approach. And see Thorium Remix 2011 which presents the case for LFTR.

7 of 218 comments (clear)

  1. Um by Anonymous Coward · · Score: 5, Insightful

    What the hell am I reading?

    >Disaster preppers have a saying, "two is one and one is none," which might also apply to 24x7 base load energy sources that could sustain us beyond the age of fossil fuel.
    How does a non-nonsensical saying apply to energy? Explain yourself.

    > I too was happy to see Skunkworks' Feb 2013 announcement and the recent "we're still making progress" reminder. I was moved by the reaction on Slashdot: a groundswell of "Finally!" and "We're saved!"

    How did we move from crazy people sayings into nuclear energy? This is the worst written summary on /. in a very long time.

    Also, learn what a comma is and how it's used. For the love of god, this reads like stream of consciousness passed through google-translate a few times.

  2. Closer to market by mfwitten · · Score: 4, Insightful

    If you've got a valid business plan, then get investors like any other business.

  3. Re:Fission is Dead by gewalker · · Score: 5, Insightful

    Let's say I had a tested, working LFTR design. Do you really think it would be very hard to convince the public that it is inherently safer than other fission designs. Safer than a coal plant. Safer than hydroelectric. It is pretty easy to understand that a plant that is inherently impossible to cause a melt-down might be a different kind of plant than a light-water reactor design.

    True, there is radiation, but it is very modest. Few people seem to have NIMBY issues with LWR reactors based on the normal radiation. It is the fear of a Chernobyl event.

  4. Re:Fission is Dead by Smidge204 · · Score: 5, Insightful

    Safer than hydroelectric.

    Including Chernobyl, there have been something like 56 direct fatalities, 4000+ deaths from cancer attributed to the radiation, and 350,000+ displaced peoples due to fission reactor failures. I'm not aware of any deaths *directly* attributed to Fukushima but let's round that off to an even 60.

    Banqiao hydroelectric dam collapse: 26,000 drowned, 145,000 dead from disease and famine, 11+ million displaced.

    Adjusted for GW capacity, hydroelectric power (970GW) is an order of magnitude more dangerous than nuclear (372GW).

    Ban hydro power! ;)
    =Smidge=

  5. Re:Fission is Dead by fustakrakich · · Score: 4, Insightful

    It's not about nuclear itself. We just can't trust the people running the industry, and that includes government oversight. They will cut corners and claim cost overruns every chance they get. It turns out that big business is just as funky as a traveling carnival show... They're all a bunch of hucksters. This is what makes nuclear look bad. Well, that, and a couple of well publicized accidents, caused by what? Corner cutting and corruption. Nuclear can be very safe and secure.

    --
    “He’s not deformed, he’s just drunk!”
  6. Re:Fission is Dead by TheRealHocusLocus · · Score: 4, Insightful

    So far every "inherently impossible" to meltdown design has been proven to be susceptible.

    Liquid fuels are already 'melted' while in operation, but I do catch your drift, as in runaway catastrophe.

    Meltdown with atmospheric release of radioactivity is possible where decay heat comes into contact with water (hydrogen, Fukushima) or graphite (Chernobyl). While the danger of graphite ignition pebble reactors has been posed and disputed, they punt by saying, we'll keep a runaway pebbl;e reactor it contained and starved of oxygen (via inert gas) and it won't be a problem.

    My worst case scenario is worse than theirs. My LFTR-killer event involves an explosion powerful enough to destroy the containment vessel and building, in the rain. It would be an awful mess. But the salts would merely solidify and remain bound to the heavy elements mixed in, and aside from some steam which would be barely radioactive (because they only react with water slowly) there would be no need to evacuate the day care center over the ridge as the cleanup begins.

    So a LFTR 'disaster' is merely a local mishap. To solve the world's energy problems one could not hope for better.The Thorium video describes the failures at Chernobyl and especially Fukushima in greater detail.

    --
    <blink>down the rabbit hole</blink>
  7. There is no such thing as a "safe" fission reactor by Required+Snark · · Score: 4, Insightful
    Safety is not about technology, it's about human error. As long as people do dumb things, no design will prevent a catastrophe.

    Look at the three big reactor failures: Chernobyl, Three Mile Island, and Fukushima. All three were caused by human error. For Chernobyl, it was a dangerous design and running dangerous tests. For TMI, it was a less dangerous design, and they still screwed it up with bad procedures. For Fukushima, they made a series of globally bad design choices because they refused to consider realistic worst case external events. Plus they uncovered a flaw in the containment structure design that lead to the hydrogen explosions.

    All of these are human error.

    And it's not just reactors. The British Petroleum oil platform blowout in the Gulf of Mexico was human error. The sinking of the ferry Sewol in Korea was human error, as was the sinking of the Concordia off of Italy. BP also had a refinery blow up in Texas because of bad operations and ignoring a known problem with volatile fume leakage.

    So no matter how secure a technology looks, it will still suffer a complete worst case failure. Assuming anything else is wishful thinking.

    What's the worst case for LFTR? No one seems willing to even talk about it. It's remarkably like the head in the sand attitude that lead to the Fukshima disaster.

    So here's a question: what happens when a molten salt containing fluorine, uranium, thorium and other miscellaneous radioactive elements comes in contact with water? Does it explode? Does it burn in air? How toxic are the substances entering the environment? (Trick question: both uranium and fluorine are very toxic elements. Fluorine forms many toxic compounds with carbon.) What is the equivilant explosive energy of tons of molten uranium salts?

    If it is burning, how do you put it out? (Note: with fluorine compounds water is a bad idea. It's explosive.) How do you build a containment vessel that will withstand all of that? How will the cost of proper containment and emergency planning and equipment impact the economics of power generation?

    A burning LFTR makes a burning graphite reactor seem like a campfire for a marshmallow roast. Good luck with that.

    --
    Why is Snark Required?