Superconducting Tape Leads To A Smaller Tokamak

Attempts to make a viable nuclear fusion reactor have on the whole been the domain of megabucks projects supported by countries or groups of countries, such as the European JET or newer ITER projects. This is not to say that smaller efforts aren’t capable of making their own advances, operations in both the USA and the UK are working on new reactors that use a novel superconducting tape to achieve a much smaller device.

The reactors in the works from both Oxfordshire-based Tokamak Energy and Massachusetts-based Commonwealth Fusion Systems, or CFS, are tokamaks, a Russian acronym describing a toroidal chamber in which a ring of high-temperature plasma is contained within a spiral magnetic field. Reactors such as JET or ITER are also tokamaks, and among the many challenges facing a tokamak designer is the stable creation and maintenance of that field. In this, the new tokamaks have an ace up their sleeve, in the form of a high-temperature superconducting tape from which those super-powerful magnets can be constructed. This makes the magnets easier to make, cheaper to maintain at their required temperature, and smaller than the low-temperature superconductors found in previous designs.

The world of nuclear fusion is a particularly exciting one to follow in these times of climate crisis, with competing approaches from laser-based devices racing with the tokamak projects to produce the research which will eventually lead to safer carbon-free power. If the CFS or Tokamak Energy reactors lead eventually to a fusion power station on the edge of our cities then it may just be some of the most important work we’ve ever reported.

80 thoughts on “Superconducting Tape Leads To A Smaller Tokamak

  1. Fusion won’t “solve” the climate crisis. Not in the naive way media like to depict, at least.

    Don’t get me wrong — I like cheap energy as the next gal or guy. But if we don’t get our act together *right now*, perhaps we won’t have enough resources left to pursue fusion research to its happy end.

    For this, we have three sources at our disposal:

    1 don’t waste
    2 wind
    3 solar

    (3 might overtake 2).

    So,by all means, keep doing research. Keep writing about it. But mentioning fusion in the context of climate crisis is giving hope to all those still thinking they can keep their way of living because Tech Fairy is coming to save their buts.

    There’s no Tech Fairy. There is “just” tech.

    1. Wind power is horribly polluting. Even with the nuclear waste fusion produces (neutron activation), it’s still eclipsed by the unrecyclable composite waste that the equivalent number of short lived turbines create. The trials on reusing this waste are even further from environmental and economic viability than fusion.

      The real solution until we get fusion going is fission.

      1. I think the real solution is to limit air and vehicle travel, eliminate the everyday habit of replacing useful, functioning electrical goods just because we want the newer version, cut our meat intake and opt for local produce.

        The more people who push that message, the more normalized it becomes.

        1. I see these comments a lot but they never specify who needs limits. The reality is that the US for example is a minority in global pollution. The ones that top that list are china and India and both have outright said their priority is growth, with pollution a distant second. They both top the charts on coal usage and are building *more* coal plants.

          The reality is the planet can easily support a couple billion people living in comfort in an advanced society. What it can’t support is 10+ billion all living like that.

          So what’s the plan? Make everyone go back to the the stone age in some attempt to support 10s of billions of humans at the minimum level for survival? Because the reality is that once we stop all those advanced (and polluting) techniques for growing crops the population will decrease all on its own.

      2. Until wind and solar have a practical storage energy storage method, they require full load capacity conventional power plants as backups. Make as great an effort as possible to develop and replace current, Cro-Magnon technolgy reactors with:

        Generation IV fission reactors

        Relative to Gen II-III, advantages of Gen IV reactors include:

        Nuclear waste that remains radioactive for a few centuries instead of millennia
        100–300x energy yield from the same amount of nuclear fuel
        Broader range of fuels, including unencapsulated raw fuels (non-pebble MSR, LFTR).
        Potential to burn existing nuclear waste and produce electricity: a closed fuel cycle.
        Improved safety via features such as ambient pressure operation, automatic passive reactor shutdown, and alternate coolants.

        1. if aviation was treated in the same way as nuclear power, you would travel slowly on tail dragging prop jobs in unpressurized cabins. and they would crash a lot, as any advancement to make them safer would be considered not worth the risk. hipsters would just insist everyone take the train.

        2. One example of a GenIV design:

          At least one calculation had the IFR able to meet 100% of the United States’ energy needs for a century, using only existing LWR waste stockpiles as their input. That study was over a decade ago – now we have even more LWR waste!

          Even Gen3 reactors with reprocessing would be a major improvement over the status quo of SLEXing old dangerous clunkers because people are afraid of nuclear. (Definitely a law of unintended consequences here – block construction of new plants with modernized safety systems, the end result is old clunkers like Fukushima get SLEXed and have an accident when they should have been decommissioned due to their age.)

      3. Wind turbine waste is currently slightly less than how much coal ash is generated annually. Also if you consider the tons of CO2 generated those blades that make for wonderful photo-ops are a drop in the bucket. People seem to work on the basis of “can’t see, don’t care” when trying to draw criticisms.

      4. Nuclear fusion produces NO radiation on par wit fission & unlike fission which carries the risk of meltdown plus AMPLE amounts of space needed to store the radiation which will last thousands of years and needs to be safely stored for the entire time or else the surrounding area will get contaminated… Fusion doesn’t and if the fuel supply needed for fusion runs out… It’ll just shut down…. Whereas if the power supply for fission jus suddenly runs out then we have meltdown…. Fission is dangerous & unreliably unsafe..

    2. This.

      Fusion, if we get it working, will permit next advances of humanity, just like fossil fuels accelerated industrial revolution. But it won’t happen in the next two decades, while hopefully a lot of other carbon reductions will.

          1. A few things: I’m a former particle physicist, I worked on muon catalysis for a while, and explored a lot of other approaches to controlled fusion. I don’t really see how to make controlled, net-positive fusion practical without finding some new, yet unknown physics – hope you can imagine how highly improbable such a scenario is.

            Yet, I value all the fusion research, ITER included – not for the stated end goal (trust me, most people working in those projects do not believe it’ll ever be achieved), but for all the insane side effects of such research. Just think of how massively superconductivity research was advanced as just a side stream of fusion research.

          1. This is exactly why fusion research is important – it’s producing tons of advancements in related (and unrelated) domains. But fusion itself is not going to become practical unless we find some new physics that breaks everything we know so far.

            If we assume that plasma confinement problem is solvable (which is a huge “if”), there are more pressing issues: very quick degradation of all the materials used in the build, thanks to alpha particles produced in the process. No solution so far, and unlikely no solution with the known material science. Either your reactor does not live long and therefore is not practical in any way, or you have no way to extract the produced energy, which is also not really practical.

      1. There’s nuclear fission that works and works well. Also funding research on fission will make more economical reactors that could use other fissile materials, like thorium. It’s dangerous? Yes, but all industrial activities and energy production are dangerous. Even renewables have destroyed houses and killed thousands of people and the deaths caused by burning coal, petroleum, and natural gas are a lot. But of course when someone got killed due a methane leak in the house, it’s going to be a 1 minute on a local news channel.

        1. How is it dangerous?
          Here’s the list of deaths from nuclear power (not including “power plants” producing nuclear weapons, like WIndscale in the UK).
          Fukushima: 1 death from cancer.
          Chernobyl: 31 exploded, 28 radiation exposure, 19 cancer from being downwind.
          Cigar lake, Canada: 1 eaten by wolves while mining uranium.

          Fission is the safest power source we have. You could dispose of the radioactive waste as a powder in the wind and still have less deaths than by generating the same amount of power with coal.
          I’m confident more people die from cancer caused by installing solar panels without sun screen.

          1. I’m afraid Russia and Japan (and 3mi) have triggered the Hindenburg effect in the eyes of the general public. Even considering how Germany are at the heart of the all-knowledgeable and enviro righteous EU, even they’ve kicked fission power to the kerb. France seem the only real winners. Worldwide fission power generation, instead of increasing, has merely leveled off in the last 20 years (

    3. > all those still thinking they can keep their way of living because Tech Fairy is coming to save their buts.

      Given that individuals are essentially powerless in fighting climate change – because the options given are basically to stop consuming (food, energy, materials, land…) while other people keep multiplying and taking up those resources instead (Malthusian trap: you can’t feed the world and reduce consumption at the same time) – the only solutions that can help are necessarily going to be some sort of “tech fairy” solution or a breakthrough at the supply side.

      It’s the “not living their way” that is the impossible demand – because people can’t just drop what they’re doing and start living in a barrel, and even if they do it doesn’t help. If the economy stalls because people stop buying consumables, the whole system goes down and the solutions become impossible to maintain. Furthermore, we don’t have the technology to scale up wind and solar, so if you’re in a hurry, go out on the streets and demand nuclear power back.

      1. Although individuals have very little power, they are not completely powerless. Voting actually works. And it works both ways.
        For one, Amsterdam is a city of a million people and one of the biggest car arteries has been closed off, reducing local pollution considerably and working on getting rid of one of the structural causes of our problems: driving cars, whether they’re electric or not. This is a direct result of voting for the Green Party.
        Aside from that, ‘stop consuming’ is not just about food. It’s also about things that aren’t necessary to buy. The western world eats way too much meat – go back to the consumption of pre-WW2 and fill the resulting hole with vegetarian stuff. The world can be fed with much less pollution. There’s also too much unrepairable stuff. We can have nice things that are less polluting over their life span, if we demand them to be repairable and demand the software to not bloat with update after update.
        The annoying and sad thing is that many parties who actually have the desire to do something about pollution and climate change, are also tricked into believing nuclear power is dangerous and dirty, while i agree that for the next 50ish years, it’s the only way to guarantee a stable supply of energy, on the inevitable days that there’s too little wind and solar.

        1. >Voting actually works. And it works both ways.

          People vote without long term consideration, which causes the votes to swing backwards and forwards: when the economic and social consequences become apparent, the voters turn their backs and go the other way.

          In the case of Amsterdam, the voters will literally go the other way, as they can no longer drive down roads that don’t exist. It may well be that the decision will backfire on itself by promoting more field-side supermarkets and services outside the city and a dispersed population, which promotes more driving and more pollution – just elsewhere.

        2. > ‘stop consuming’ is not just about food. It’s also about things that aren’t necessary to buy.

          We’re living in a services economy that is based on continuous consumption. It is necessary to buy. If you stop, people won’t get your money, which means you won’t get their money in return, which means the economy starts to stall. The continuous circulation of money in exchange is what keeps the goods moving, but that requires someone else to consume goods so you can sell them the goods to have the money to buy goods yourself, and vice versa: everyone has to consume in order to be able to consume.

          The more you can make someone else consume, the more you can consume yourself since you’re effectively taking a “cut” of whatever they’re consuming, and they’re taking a “cut” out of whatever you’re consuming. If you should stop for any reason, the other guy would get less, which means you’d have even less – a market collapse.

          1. This is of course in contrast with the “old” system, where every consumer was met with a person who produced stuff and things were generally made according to need.

            Since this system has been made obsolete with automation and outsourcing, people have to consume in order to earn money to consume. Whether you need something in particular is irrelevant – you must convince people to want it even if they don’t need it, and by proxy you will convince yourself to want things you don’t need.

        1. It won’t change arbitrarily.

          The reason the ants are powerful in groups comes from the hive that they’re building – the system that gives them the power to maintain the system. Outside of that, they’re just single ants. Likewise for humans: we’re parts of a huge economic system which empowers us to maintain the system – if we go against the flow, we’re downright helpless.

    4. There is for example the Sun Cell from
      BrilliantLightPowerInc or there is the this
      Energy from Atmosphere (water wapor) thing
      and many more which are more promissing than fussin, fission, solor or wind.

    5. Nothing goes to waste, actually. Except helium and hydrogen gas, and the stuff that we use to build rockets of, which we shoot outside of Earth’s gravity well.

      The problem is not ‘waste’. There is no ‘waste’, ‘waste’ doesn’t exist.

      The problem is simply that the materials that we produce is too concentrated to be harmless, but at the same time not concentrated enough to be recyclable, and that we just leave a trail of it everywhere all over Earth.

      Once you realise that, you will see that it’s all about making materials recyclable and not littering it everywhere we go.

      It’s really quite simple.

    6. > There’s no Tech Fairy. There is “just” tech.

      You seem to not grasp the concept of ‘setting goals and working towards it’.

      That ‘tech fairy’ that you are mentioning, is the goal. And if we all work towards it, the tech fairy will come to life.

      It’s really only a matter of mindset. Our current mindset is the root of all problems. For 100 years, we in the ‘West’ have been gaining wealth in a destructive way. Now we know better. But we forget that we have given a bad example to the whole world, who now believes that that destructive way of gaining wealth is the only way to go.

      And maybe it’s actually true. Look at how China gained its power by acting at least as destructive as we did during the industrial revolution.

    7. thermal pollution will be the big problem in a post-fusion world. when energy becomes cheap demand for energy will rise. the thermodynamic cycle puts out considerable waste heat which needs to be dumped into the environment. higher energy demand means more thermal pollution which will continue to drive climate change. at least until we get direct conversion aneutronic reactors (and those are still going to have waste heat), which is gonna be a 3rd or 4th gen thing. first gen fusion powerplants need to use the fuels with the biggest cross section and those do not produce charged particles.

    8. So almost entire EU, USA and a few other places are eco-friendly, make plenty of wind and solar power. Still, places like Africa and everything south of USA, most of China, Russia, Belarus and Poland don’t care or can’t afford to be eco-friendly. In Poland there was law passed some years ago that makes it basically illegal to build any wind turbines. Instead Poland spent quite a bit of money to expand probably the biggest coal power plant, to demolish that expansion for some reason, while arguing witch Czech Republic because of coal mine that causes a rather big ecological problems on their side of the border.

      When developed countries are run by greedy corporations and governments full of idiots, and developing countries are constantly screwed economically, politically and socially, no amount of clean energy or better technology will save planet Earth.

      So we get this fusion thing working. Who would get it? African countries? South America? Poor regions of Asia? Nope. USA, China and some countries in EU. Those who can pay for it…

  2. Agreed, I work in this industry and everyone from c-suite down knows that this resolves a lot of problems, but has the potential to create new ones.

    Cheap energy leads to “Why bother making new toasters efficient?”, Which then leads to “oh crap, all 9 billion of us ohmic-ly heating bread is heating up the atmosphere!”..

    All to say, we all need to reduce energy consumption, regardless of the source.

    1. So we solve the new problems too.

      If energy can be harnessed pollution-free then greenhouse gases are reduced, and the heating effect of 9 billion toasters can be ignored.

      1. Not really. Current global warming is fuelled primarily from greenhouse gases, but there’s also a small contribution of heat from energy consumption itself. Sure, it’s a negligible amount, but not so far off, maybe 2 orders of magnitude, which could become a problem if we were to find a really cheap source of energy, even if it’s “clean”.

        1. Humans add 0.04 W/m2 while the sun adds 340 W/m2 on average. According to the definition of an “order of magnitude”, that would be a ratio of 0.85 x 10^4 which says the difference is four orders of magnitude.

          The order of magnitude for a number N = a10^b where “a” must be between 0.3…3 and “b” is the order of magnitude you’ll find in result. However, it would be much easier to just note that people put out 8500 times less heat than the sun onto the earth.

          1. What matters is not the total amount dumped, but the difference between the heat in (from the sun, the earth’s internal heat and humanity) and the heat out (radiated out to space). If the planet doesn’t heat up or cool down, this difference is zero. Greenhouse gases are breaking this balance by a relatively small amount, I don’t remember by how much, but maybe something like 1 part in a thousand. My “two orders of magnitude” figure were compared to that difference.

          2. You have to remember that much of human “waste heat” is actually just recycling latent heat that was already in the system, such as potential energy in a river or sunlight embedded in a tree, or heat pumped out of the environment itself through a literal heat pump (refrigeration), etc.

          3. Yes, much of it is, but most of it is rapidly liberating trapped energy condensed eons ago, i.e. fossil fuels and nuclear energy. Refrigeration also produces heat, a 1 kw AC unit pumps whatever amount of heat it pumps and produces, well, 1 kw of heat in the process.

      2. How long it would take to replace power plants all over the world, including all the poor countries -that can’t afford it? How long for all cargo ships to be upgraded or replaced with fusion-based propulsion? And are we going to make all the airliners carry fusion reactors?

    2. In current understanding of physics , if kinetic energy is pulled e.g out of the water, and use that kinetic energy to heat up a toaster. Would that heat release be more than the heat released if the water slows down naturally and almost comes to a standstill in the sea. Should be the same though.
      There problem is more the artificial redestribution of the heat. Wich will result in a natrual backdistribuition (extreme weather)
      Although fission seems interesting in that reagard since fission would naturally take much longer to release that amount of heat. So conentrating it and speeding up this release on a big scale seems problematic.

      1. Your toaster would make less heat, because there are efficiency losses along the power grid and in the generator itself.

        But if you count all the losses and the amount you use to toast your bread, it would equal exactly the amount of heat you release by allowing the water to flow into the sea.

        1. There are complications. Waterfalls, lakes (artificial and natural), etc. cause evaporation which cools the air. OTOH the added moisture in the air is alleged to be a very potent greenhouse gas. I doubt that these things will be honestly modeled by either side.

    3. The “carbon footprint” meme was crafted by BP’s public relations team after deepwater horizon. Using your toaster isn’t heating up the atmosphere. Globalism is.
      Less than a dozen container ships equal the output of every land vehicle on earth combined. Private little reductions and masochistic austerity won’t do squat.

      We have to stop exploiting this global economic zone thing and start being self-sufficient nations again. Which is exactly why you see the globos pushing greenwashing so hard, and all the stuff they suggest is a joke.

      1. >Less than a dozen container ships equal the output of every land vehicle on earth combined

        Output of what?

        A container ship equals about 2,000-3,000 average cars in terms of fuel consumption, and there are more than a billion cars and other vehicles on the roads globally. If you’re talking about carbon emissions from fuel, vehicles on land generate about 50,000 times more emissions than a dozen container ships would.

        1. [citation needed]

          A May 2018 study from concluded that CO2 emissions from the global road-vehicle fleet are 2 to 4 times the CO2 emissions of the global maritime fleet. The NOx emissions are about equal. The SOx emissions of the maritme fleet probably exceed the SOx emissions of the road-vehicle fleet.

          The maritime SOx emissions could be reduced by using lower-sulfur fuel.

  3. fusion has been 10 years away for as long as I’ve been reading about it (1970 or so).. I suspect it will be 10 years away when my grandchildren (who I don’ have yet) are my age…

  4. For all the tax money spend on fusion, we could have build multiple solar-panel-and-all-the-other-stuff-that-it-needs factories to produce cost free panels for every roof all around the world.

    1. For all the money that we gave to Bill Gates for his overpriced Operating Systems and Office suites, we could have built multiple solar-panel-and-all-the-other-stuff-that-it-needs factories to produce cost free panels for every roof all around the world.

        1. There are better and less expensive operating systems superior to Windows. There are free office suites as good as Office. Taken in the full context of available alternatives, microsoft has been a net burden on the world.

  5. I think that a lot of the people saying that we should invest more in nucleair fission instead of fusion, is overlooking another promise of nucleair fusion: small fusion reactors that can be safely operated by Joe Public to power their house and car.

    Try that with a fission reactor…

    Of course, we need to make a bunch of breakthroughs still. We can’t even make a big fusion reactor right now. But once we do, I’m sure we’ll get into an accelerated flow of innovations.

    1. You’ve seen too much Iron Man. Fusion requires giant reactors and I don’t see the average person safely operating a device that creates temperatures hotter than the sun with supercooled magnets in their garage.

    2. Huh? Joe Schmoe can, theoretically, operate an RTG. And probably there’s quite a few Schmoes doing just this right now, with the RTGs that went missing from the old Soviet lighthouses.

      As for fusion, there won’t be any fusion reactors, no matter large or small. Unless there’s some new physics discovered (which is unlikely), with our current understanding of what the world is made of, we won’t build a net positive fusion reactor.

    3. i saw sometime ago a solution of instead of trying to go into fussion we should go to 1 home small fission reactors.
      Looked like a great ideia.
      But with all the fear that the public have of nuclear (fission) reactors i dont think that would be ever adopted

  6. Anybody read Tom Murphy of lately? In his book on p.258 he writes:

    “If we tried to get all 18 TW from this uranium supply, it would last less than 4 years! This does not sound like a salvation. Proven uranium reserves would last 90 years at the current rate of use (~1 TW out of 18 TW), so really it is in a category fairly similar to that of fossil fuels in terms of finite supply. To be fair, proven reserves are always a conservative lower limit on estimated total resource availability. And since fuel cost is not the limiting factor for nuclear plants, higher uranium prices can make more available, from more difficult deposits. Still, even a factor of two more does not transform the story into one of an ample, worry-free resource.”

    18 TW is the current yearly power usage of the world.

    You can get the book here:

    1. Uranium makes up 2.8 parts per million of the Earth’s crust. It’s a bi-product of digging up and refining pretty much anything. The is especially true of coal and rare earth elements used to make wind turbines.
      It we ran an 18Tw/year breeder reactor, we could generate a years worth of fuel in the first four months of the year just from fissile materials appearing as waste.
      If we dug up everything fissile we could get out bucket exicators on, that power plant would still be running after solar and wind stops working – because the Sun stops in four or five billion years.

      1. That 2.8ppm is for U-238 which has to be enriched first. The directly useable U-235 is rather scarce with only 0.02ppm.
        The stuff out of breeder reactors can be used for dirty bombs as well and should be pretty hard to regulate, which is why we’re not using it already by now.

        1. I’ve never understood the dirty bombs argument. The countries that can make breeder reactors already have access to H-bombs, why are we worrying about dirty bombs?

        2. Uranium 238 that makes up 99% of Uranium in the Earth crust is stable though it is also fissile. By that I mean we know how to bulk transmute it into Plutonium 239, we can use this for power generation.
          If 2.8ppm of the whole planet Earth is too small an amount for you, there’s also Thorium that is also fissile.
          As for dirty bombs, can you describe any hypothetical attack that could possibly cause more harm than an equivalent MW/h coal power station, being placed upwind of a city?

          I’m sure that the lazy arguments against nuclear power are coming from the natural gas industry, e.g: Takes too long to build, we can’t possible store a few contains of waste for 300 year, it produces expensive power, the fuel all comes from warlords, we’re about to invent batteries and cheap solar panels any minute now, it’s racists, humans can’t be trusted to run a nuclear plant, nuclear power is the same thing as nuclear weapons.

          I truly believe that if any of you want to do something good for society, there’s nothing that would give you a better return on your efforts than promoting nuclear power. Just imagine every 3rd world country having cheap energy without adding to the atmospheric CO2.

          1. I have never seen an atomic bomb do anything good, really.
            And you may need the fission reactors anyhow to produce enough tritium, which you will need for the fusion with deuterium.
            So, I will neither promote nuclear fission, nor nuclear fusion.

  7. There something I don’t understand about how this is supposed to work.
    We already have fission power which we don’t use, if we get fusion power won’t we just have a second (more expensive) transmutation based energy source that we also won’t use? It’s not like the people who complain about the radioactivity from fission are going to not complain about waste generated by H + H => He + neutrino, turning the surrounding equipment into an assortment of lethal isotopes.

  8. Now, back to the original post without discussing the pros and cons of power plant technology (we’ve had that at length, and there’s no new information apart from not everyone’s opinion was mentioned).

    As fas as I understood the TOKAMAK size is determined by plasma “bleeding” – The plasma just won’t stay where you’d need it. Smaller magnets would not solve this as long as the enclosure diameter stays the same. And you need an amount of enclosure to reach minimum fusion state.

    It’s probably good to reduce the magnet size, but isn’t the bleeding rather solvable by the stellarator configuration than with TOKAMAK?

    And even the stellarator calculations had to be adapted due to the bleeding effect. Early calculations projected a much smaller reactor core.

    Usually math can calculate anything and physics has to perform, but sometimes physics just ignores this and comes up with different ideas.

  9. What I’m getting from the article that nobody mentioned in all the comments so far is the switch to high-temp superconductors instead of low-temp. That reduces the cooling requirements by something like an order of magnitude. (~5 K vs up to 70 K)

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