Of Particular Significance

Fusion Confusion

POSTED BY Matt Strassler

POSTED BY Matt Strassler

ON 12/15/2022

By now the word is widely out that Tuesday’s fusion announcement was less of a news flash (as I initially suggested) and more of a overheated news flicker. The politician-scientists who made the announcement that they’d put 2 Megajoules of energy into a pellet of nuclear kindling, and gotten 3 Megajoules out from nuclear fusion, neglected to mention that it took them about 300 Megajoules — about 100 times as much energy from the electrical grid — to run the experiment in the first place. In other words, they said

  • -2 + 3 = +1 !!! Breakthrough!!!!!!!!!

whereas anyone who knew the details would have said

  • -300 – 2 + 3 = -299 ? Cool bro, but…

In other words, it was a good day for fusion, but not nearly good enough.

To be fair to everyone, the scientists involved have made tremendous progress in the last few years; they weren’t even close to getting this much energy out until 2021. They’re 10 times ahead of where they were in 2019 and over 100 times ahead of where they were in 2010. If they can continue this progress and figure out how to get another 100 times as much fusion energy out without requiring vastly more electricity, then this all might start to be somewhat interesting.

But even then, it seems it’s going to be very tough to get anything resembling a power plant out of this fusion strategy. Experts seem to think the engineering challenges are immense. (Have any readers heard someone say otherwise?) Perhaps Tokomaks are still the way to go.

I’m annoyed, as I’m sure many of you are. I was myself too trusting, assuming that the politician-scientists who made the claims would be smart enough not to over-hype something that would get so much scrutiny. It’s the 21st century; you can’t come out and say something so undeservedly dramatic without the backlash being loud and swift. Instead they played the political spin game as though it was still the 1970s. I think they were hoping to convince Congress to keep their funding going (and because of an application of their work to nuclear weapons, they may succeed.) But when it comes to nuclear fusion as a solution to our energy/climate crisis — did they really think people wouldn’t quickly figure out they’d been duped? Seriously?

To quote one of the comments on my last post, from Blackstone, “It seems to me that this whole civilization desperately needs a reality check.” I completely agree. We’re so driven now by hype and click-bait that it’s almost impossible to separate the wheat from the chaff. Maybe at some point the people driving this international daily drama show will realize they’re doing serious harm. Clearly we’re not there yet.

But that’s what this blog is for, as are some others in a similar vein. Hopefully I won’t make too many mistakes like the one I made Tuesday, and when I make them, I’ll always fix them. Thank you to the many commenters who raised valid concerns; I know you’ll always keep me honest if I take a false step.

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30 Responses

  1. I have to admit that I was taken aback by your positive spin on fusion, having watched Sabine Hossenfelder’s video on the hype surrounding fusion generally a year ago. Although your mistake was with the details rather than the physics, even Feynman can sometimes goof in basic physics in his area of expertise such as Gauss’s law: https://www.wm.edu/news/stories/2020/feynmans-advice-to-wm-student-resonates-45-years-later.php

    Feynman: “I probably was thinking of a grounded conducting sphere, or else of the fact that moving the charges around in different places inside does not affect things on the outside. I am not sure how I did it, but I goofed. And you goofed, too, for believing me.”

    Is it possible that Lenny Susskind may have make a mistake in his video “Demystifying the Higgs Boson with Leonard Susskind” that was mentioned in the comments under your article “Why Current Wormhole Research is So Important”?

    I know this is very unlikely, but at 35:03 in the video he says that a water molecule isn’t deflected by an electric field because the net force on it is zero because of its overall electrical neutrality. I disagree. A +q charge placed outside a hollow spherical conductor say, will polarize the charge; attracting electrons to the nearest surface, leaving positive metal ions at the furthest surface giving a net attractive force on the +q and vice versa. So likewise with a water molecule I’d expect it to be deflected by an electric field because of it being similarly polarized. I’ve found this paper: The electric polarizability of the neutron by Jörg Schmied, mayerHelmut, RauchPeterRiehs, so perhaps the effect is so small compared to the effect upon its mass, which is why Lenny didn’t mention it?

    1. I agree with you, and it is an easy experiment to, even at home. Open a water tap. Let flow a little water, approach an electrized plastic stick, and you will see the flow of water deflected, due to the polarization effect you mention. Water molecule is a polarized molecule.
      For the NIF, the officiel communication was misleading. It was the initial aim of NIF (National Ignition Facility), to get ignition (ie auto sustained fusion reaction), they finally obtained it, twenty years after, but it is to test thermonuclear bombs in the laboratory, not to get electricity, as real nuclear tests are forbidden since 1996..

      1. Thinking further about this last night, an electric dipole experiences a net force only in a non uniform electric field, no net force for a uniform electric field as in Lenny’s example, and tending to align with the applied electric field in both cases.

  2. Hello Matt. I want to follow up on your story with a related one. There is a man named Steven Krivit. He became known as the publisher of New Energy Times, which 10+ years ago covered cold fusion and LENR. After interest in the “phenomena” waned in the mid-teens, he began investigating the power gain claims made by ITER, the international collaboration responsible for the large Tokamak reactor in southern France. Between 2017 and 2022, Krivit has, I think almost single-handedly, been responsible for an enormous walk-back of false claims about the ITER Tokamak that were made by … well, almost everyone, and for decades. In short, almost nobody paid attention to the subtleties of scientific versus engineering break-even, and numerous parties played fast and loose with the truth (that the demonstration plant will have a significant negative power balance even when optimistically considering only its thermal output, not even considering the Carnot efficiency of [hypothetical] conversion of thermal output to electrical output). You can read about the false claims and their years of collateral damage here: https://news.newenergytimes.net/iter-fusion-power-output-consumption-facts-and-falsehoods/ Thanks.

  3. > But that’s what this blog is for, as are some others in a similar vein. Hopefully I won’t make too many mistakes like the one I made Tuesday, and when I make them, I’ll always fix them. Thank you to the many commenters who raised valid concerns; I know you’ll always keep me honest if I take a false step.

    Ok, I think this is a model of intellectual honesty, and surely it is one of the reasons I follow this blog and consider it the best physics blog among those I’m aware of — another reason being prof. Strassler’s ability to ‘translate’ concepts and maths for the rest of us without naive and potentially misleading analogies (see e.g. his explanations of virtual particles and of the Higgs field).

  4. A joke I just saw on the internet: how did scientists discover that they spending exceeds almost 100 times the energy gain in this fuse? With quantic calculations? Nuclear? Relativism? gravitational? No, is that the light invoice arrived ….

  5. It’s not the first that such overstated claims are made, to have break the lawson criterium. Sabine Hossenfelder made a video about that one year or two about that. They are only speaking about the energy used and received from the core of the esperiment, but are hidding all apparatus around needed for the experiment, and the energy they use.

  6. In the excitement of the announcement, everyone seemed to forget that NIF is NOT an energy program, but a nuclear security program that does a lot of science related to ignition, high-density physics, and nuclear weapon physics (see their website: https://lasers.llnl.gov/science).

    Yes, this was a huge technical and scientific milestone. No, this type of laser-driven fusion is unlikely to become a reactor that will power society. Reactor development is not in NIF’s roadmap.

    1. Which would mean that Tuesday’s announcement was probably just smoke and mirrors to justify funding with public opinion?

  7. Thannk you for this post.
    Actually this subject turned into a media show about how we humans found the magic solution against climate change, not really about the technological accomplishment. And to make things more dramatic, the input of energy was moved afrer the lasers, as if those lasers worked without any energy supply.
    Well, this necessary input of energy must be clean ad green in order to ecologically make sense. So, what do we really got?
    Well, at this stage, we need more green energy so we can produce less green energy by this method.
    Bad deal so far.

  8. The two orders of magnitude, that’s just on the electricity to laser power input side. Then there would be another order of magnitude or so discrepancy on the output side: radiation to heating steam to turbine generation to electricity. Then there is the duty cycle problem. They can get in perhaps 10 shots a week given the multi-hour cooldown time, whereas a commercial fusion reactor might need about that many per second, so there’s another almost 6 orders of magnitude. Looks like we are short by a factor of a billion for intertial confinement method to be commercially viable.

    But we do congratulate the scientific achievement!

  9. I don’t think it was coincidence that they scheduled the experiment, Dec 5th, to coincide with the heated debate on the budget on Capitol Hill. This is how white-collar welfare projects beg for more of that Uncle Sam’s “infinite pool of money”.

    Folks, that’s not a joke, I worked on the human spaceflight program for 30+ and I heard the term “infinite pool of money” by more than one NASA managers.

    Sadly, it’s all about “empire building”.

  10. This is a Wright brothers moment: laser fusion is probably not very practical but now the $$$ will flow in now someone has shown what is possible.

    As I said solar is the main competition and it is also fusion 🙂

  11. Professor, it was what I imagined when asking you how to measure such energy gain. Miracle does not exist and neither in the Sun. I am not from this area of high energies, but I believe that is impossible to imitate or simulate what the Sun does, even more in a ultra-smaller levels, neither in the incredible Tokomaks. Even more in only 0.03% of energy obtaining against 99.97% of electrical spending. Perhaps it is achieved as Assimov’s stories of level IV – Galactic Population, in stars dominated, and only out there, very far, never here on Earth. I like follow you because you are a very realistic. This is my humble opinion

    1. Well, there are many things in modern technology which would have seemed impossible a hundred years ago, or even fifty. Sometimes things take much more time than expected, sometimes much less. It’s very hard to guess how optimistic to be. Would you have guessed that fairly reliable speech recognition, and translation on demand, would be so easy, fast and cheap that they are essentially free? You can’t know how hard a problem really is until you try your best to solve it; and sometimes a new idea comes along and moves a problem from impractical to possible.

    2. “I believe that is impossible to imitate or simulate what the Sun does.”
      Unfortunately, the military can do it.

  12. Matt Strassler, thank you! While I explicitly support fusion research and have provided help to venture capital firms on this topic, I have been especially unhappy about the game playing surrounding this otherwise genuinely exciting result. My wife was curious why I was so unimpressed, and I explained those same numbers to her. I think her reaction was best described not as a scientific concern, but something simpler: “Why are they lying?”

    That reaction shows a problem that has plagued fusion research for, um… yes, about 70 years now, since the muon work in the late 50s counts (so hopeful, for good reasons at the time). One can present a precise, scientifically accurate set of facts, but spin them not with the intent to enlighten but to suppress annoying questions that might end up getting you defunded.

    My favorite example of tricky fusion wording, though I’ve not heard it lately, is “infinite power from the hydrogen in water.” Well, yeah, the deuterium comes from water, but that tritium is bred using nastily radioactive processes from lithium, and lithium most certain does not come from water.

    1. Lithium is one of the two rarest elements in the universe. Four billion years of rock weathering by the hydrosphere has leached it into the world’s evaporite basins and intermontane plains in the form of salt flats. Slightly pink crystals of lithium carbonate are common. Current annual production is ca. 150,000 tonnes. Inorder to meet demand for car batteries, mining needs to increase to 1 million tonnes by 2030 and then a 3 fold increase again by 2050.
      If there’s a morale to this then my Motorola smart phone is worth twice what I paid for it 2 years ago. Don’t discard any Li battery.

    2. There actually is a huge tritium crisis looming – that will potentially become a bigger flashpoint than the economic and military conflict for oil.

      [I have references for most of the claims below, if there is interested I can dig out the URLs] …

      Most tritium-breeder production plants have been decommissioned – the global reserves have been decaying with half life of around 12 years for at least a decade. And I suspect most of these reserves are held in nuclear weapon stockpiles.

      It is unbelievable that the ITER design does not include a Lithium breeder blanket.

      It seems to me that chasing the holy grail of positive energy balance is a smokescreen for the fact that there will not be wine to fill the chalice with.

    3. And thre is very few tritium, because if was a sub-product from nuclear bombs charge. So it would be more interesting, but difficult, to use only deuterium.

  13. Thanks, Matt. Your perspectives are always spot on – about the true significance of the fusion achievement, and about the hype and hyperbole endemic in the media and society. But, let’s forge ahead. We have important work to do…

  14. It is a breakthrough – in the science, if not the total power budget. They showed inertial confinement can generate significant amounts of fusion. That shows they have a design that works, and it’s far easier to scale and model from a working one than a non working.
    True break even, I agree, needs to be the total budget.

    And please correct me if I am wrong, but I would expect scaling to be between 1 and r – the energy required for the pressure is related to surface area, but the fusion potential is the volume that reaches the pressure, countered by more complex shock propagation effects

  15. I did harbour a degree of doubt. I recall recall reading in a 1961 issue of the New Scientist here in the UK that commercial nuclear fusion reactors were expected within 30 years
    It happens naturally in the Solar core, although this reactor is one million fold greater than the Earth’s mass. It takes about 18000 years for the radiant energy to make it to the surface to provide a black body photon spectrum at 5700 Kelvin.. Even there are explosive occasional coronal mass ejections. That can cause havoc on Earth.

  16. No worries, Matt! That was an honest mistake on your side. The news was so appealing… and it is depressing that scientists would stoop so low in hanging such bait.

    1. One of the most important things I learned as a young scientist is that the greatest scientists always admit errors. First, you’re never going to be right 100% of the time. Second, you need people to trust you. Science is not like politics; mistakes are easily discovered and they are usually unambiguous. Reputation matters.

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