Latest International Tokamak Project Plans Plasma Net Gain Goals in 2039

The latest (sept 2018) ITER Research Plan within the Staged Approach (Level III – Provisional Version) plans for plasma net gain goals to be achieved in 2039.

What is Q?

What then is the meaning of Q?

Quantitatively, Q is the out-versus-in power amplification ratio of the fusion reaction: the ratio of the amount of thermal power produced by hydrogen fusion compared to the amount of thermal power injected to superheat the plasma and initiate the reaction. ITER is designed to produce plasmas having Q over 10: meaning that injecting 50 megawatts of heating power into the plasma will produce a fusion output of at least 500 megawatts.

New Energy Times indicates that ITER will need 300 megawatts to operate. 500 megawatts might come out as heat.

Plasma energy breakeven, or Q=1, has never been achieved in a fusion device: the current record is held by the European tokamak JET (UK), which succeeded in generating a Q of 0.67. ITER’s Q value of over 10 makes it a first-of-kind machine
How did ITER’s designers choose the specific Q value? Accounting for the size of ITER’s vacuum vessel (830 cubic metres) and the strength of the confining magnetic field (5.3 Tesla), the ITER plasma can carry a current of up to 15 megaamperes. Under these conditions, an input thermal power of 50 megawatts is needed to bring the hydrogen plasma in the vessel to about 150 million degrees Celsius. This temperature in turn translates to a high enough velocity, among a sufficient population of hydrogen nuclei, to induce fusion at a rate that will produce at least 500 megawatts of thermal power output.

Why stop at a Q of 10? Why not design ITER for a Q of 30, or 50? The answer is clear: expense. For tokamaks, size and magnetic field strength matter. In simple terms, increasing Q would require an increase in the major radius or in the magnetic field strength. Either approach would have increased the cost of the device unnecessarily, whereas the achievement of Q ≥ 10 is sufficient to allow the primary scientific and technology goals of the project to be satisfied.

And a related question: Why not design ITER to produce electricity? This would also have required an increase in cost with no great benefit to the goals of the project. ITER is an experimental device designed to operate with a wide range of plasma conditions in order to develop a deeper understanding of the physics of burning plasmas, and to allow the exploration of optimum parameters for plasma operation in a power plant. The addition of the systems required to convert fusion power to high temperature steam to drive an electricity generator would not have been cost-effective, since the pattern of experimental operation of a tokamak such as ITER will allow for very limited generation of electricity.

Commercial fusion plants will be designed based on a power balance that accounts for the entire facility: the electricity output, sent to the industrial grid, compared to the electricity consumed by the facility itself—not only in tokamak heating, but also in secondary systems such as the electricity used to power the electromagnets, cool the cryogenics plant, and run diagnostics and control systems.

There are many possible risks at every step as they try to start experiments and then scale up. Risk to the optimization of fusion power in DT plasma scenarios towards 15 MA/5.3 Tesla Q = 10 (~ 50 s) demonstration

By this stage of the operational plan many of the general risks to the achievement of the ITER Q = 10 goal may materialize. These are general to the project goals and are discussed in Appendix J. Below we discuss the specific risks that can affect the operational plan in this phase:
* H-mode confinement insufficient when integrated with ELM control by 3-D fields with invessel coils (plus pellet pacing) to achieve Q = 10 or ELM control capability is insufficient for 15 MA due to hardware limitations. This would require a reformulation of the research program above the plasma current level on which either of these two issues is identified.

Possible mitigation strategies would consist of:
a) switching to the hybrid/advanced scenario development at this stage and proceed to its optimization for Q over 5 and/or
b) to proceed to develop other high confinement regimes ELM-less regimes such as QH-mode or I-mode at this stage.

* Predictive and interpretative modeling of particle and thermal transport through the core to the edge, and of alpha-particle behavior required to develop the scenarios and burn control within them are not mature enough. This will require the progress of the experimental program to be based mostly on an empirical basis and, thus, slower progress of the research as the steps in Ip/Bt
, additional heating level, T-fraction, etc., may have to be smaller than strictly required in order to ensure that the plasma in the scenarios remain integrated with the operational/hardware constraints and MHD stable to ensure low disruptivity.

* Tritium throughput provided by the T-Plant not sufficient at the beginning of the experimental phase. Although it is expected that the T plant will be able to provide the required throughput to sustain Q = 10, ~50 s operation by the end of this operational phase, it may not be able to provide the required throughput at the beginning when 9.5 MA and 12.5 MA DT plasmas with high T-fraction are foreseen to be explored.

* Nuclear heating and/or AC losses of the superconducting coils are found to be much larger than expectations.

* Flux swing provided by the CS/PF system marginal for H-mode operation at 15 MA.

Research Program Accompanying Construction
5.1 H-mode issues

The research in present and near future tokamak experiments (ASDEX-Upgrade, DIII-D, EAST, JET, JT-60SA, KSTAR, WEST, etc.) should be focussed towards H-mode research in plasmas with the specific features of the ITER H-mode plasmas, in order to understand and develop validated models that can be used to predict plasma behaviour in H-mode scenarios in ITER. This involves not only the study of stationary conditions but also of the access/exit phases to/from H-modes, where plasma behaviour is already more difficult to control in present experiments, particularly with W PFCs. In ITER this is further complicated by the relatively low margin of Psep/PL-H and the need to maintain ELM control in these transient phases.

5.4.5 Impact of scenario development issues on operation page 300

Scenario development traces the progression of the ITER Research Plan. It is important that at each stage, the new scenarios that need to be explored can make use of the development and understanding gained in previous ITER operational phases. PFPO-1 will dedicate a significant fraction of experimental time to the assessment and optimization of control schemes that will be the basis of operation in PFPO-2 and later phases. For example, plasma initiation and start-up in the hydrogen phase will address several fundamental issues for all future operating scenarios and control schemes. Plasma breakdown, possibly assisted with ECRH, and early divertor formation will be tested. Model validation to enhance the confidence in predictive simulation of the next operational phase scenarios will accompany the execution of the ITER Research Plan.

The development of the ITER Research Plan will also benefit from validation of plasma scenario modelling tools on present tokamaks, including models for plasma initiation, control schemes, and models to describe the evolution of the temperature, density and current profiles. In particular, radial transport models for electron and ion energy and particles in Ohmic and L-mode plasmas that
were developed many years ago should be re-examined using the more extensive diagnostic capabilities of present devices so that they can be used to plan more optimal ITER ramp-up scenarios that maintain the internal inductance, li , within an acceptable range for control.

The basis for establishing ITER baseline Q = 10 DT operation, the initial major goal of the ITER Research Plan, is reasonably well established. But the experimental development of advanced (i.e. hybrid and steady-state) scenarios is more challenging, as they require operation at the limits of the hardware capabilities of any given tokamak where they are explored (i.e. operation at high power for a maximum time duration, close to plasma stability limits, etc.). With regards to operation of
ITER in regimes with enhanced core confinement, such as hybrid scenarios, but especially those that feature ITBs, none of the predictive models for such regimes are as yet in a position to make reliable projections. For the global scaling approach, the limitation may be intrinsic, in that the development and sustainment of ITBs depends on local plasma parameters (i.e. on detailed plasma profiles), which are not captured in scalar databases. For the transport models, while progress has been made in replicating ITB formation and sustainment, further work is required before projections can be made with confidence of such regimes to ITER.

34 thoughts on “Latest International Tokamak Project Plans Plasma Net Gain Goals in 2039”

  1. Why’ll the earth slowly burns up thousands of scientists & Engineers waste their time whilst draining tens of billions every year to try to achieve what that yellow spot in the sky does every day. This is madness, the money and skills could be used in the fight to lower the coming heat on earth.

  2. So by “Panama Scandal” you mean “a few newpaper headlines for a week then everyone forgets about it”?

  3. ? Carbon Engineering, according to their website, is all about making synthetic fuels – the power source to do it is optional.

  4. John Bucknell (former SpaceX engineer) reckons you could produce methanol at USD 1.23 per “gallon of gasoline equivalent energy” if you had Thorcon’s molten salt reactors:

    Some gasoline would still get pumped (e.g. the stuff just below the surface in Saudi) but most of today’s reserves would be uneconomic to extract.

  5. Iter can be beaten on arrival by the breakthroughs of US private companies (US Nuclear, Lockheed-Martin). In such a case, there would only remain huge debts to the states involved. They do not need that. Mega-international financial scandal in sight …

  6. True, but it would still be cheaper to pump oil out of the ground.*

    If you’re worried about GHG, the energy and capital cost to suck it out of the air e.g. Carbon Engineering and capture it is still less than synthesizing the fuel.

    *for any reasonable cost of cheap electricity

  7. Oil, coal, gas, wind could become obsolete with cheap working fusion reactors.

    Oil is still safe unless someone makes a reactor (including all shielding) that will fit under the bonnet of a car.

  8. 1 nuclear reactor costs 5000 – 10000 million dollars and they are spending what like couple of 100 millions per year in private fusion? It is a f****** joke. JOKE JOKE.
    I would expect 10s biilons of dollars or even couple 100 billions of dollars in private fusion, since the rationale and benefits are so big.

    Iter is massive, based on old designs, partly build, fixed, not agile, they probably can’t just replace the magnets. MIT Sparc seems great, better magnets, much less cost, could be build faster, they managed to get some money but still too slow and not enough agile in my opinion.

    Magnets are one of the key technologies and are they spending billions of dollars for them? Doubt it, some small teams working on it. At least there were some recent magnets discoveries and they look so promising. Skunk works were also complaning that they could build small reactor but the limiting factor are magnets, better magnets and they could do it.
    But magnets are getting really, really good. 200 % increase in magnet strength and you could build 16 times smaller fusion reactor for same output, until you hit some structure integrity boundaries.

    Lasers are getting really, really good and pretty fast. They are almost there and still lack of some serious funding, some small teams studying it, NIF is pretty old, and I can’t reacall one larger private team working on geting fusion done with lasers.

  9. Two things. First off, I think they should redesign ITER for higher magnetic fields. It would take switching to high Tc-superconducting tapes and making the structure stronger.

    Second, I am much more curious of the MIT approach with high magnetic field. How are they doing? Are they funded? Have they started building their prototypes yet? To me, it seems like a vastly better approach than ITER…

  10. How about bringing some natural uranium and breed it, or breed thorium? I know we have plenty of both, and we will be able to ferry it from earth to orbit fairly cheaply once the Space X-fleet is up an working, right?

  11. Energy production is 1,4 trillion dollar market. Oil, coal, gas, wind could become obsolete with cheap working fusion reactors. They don’t want to loose their sources of income.
    They look after their own asses and not for the benefit of humankind.

    So many scientists working on ITER, all those different countries, so old designs, so much paper work, so much studying and pork doesn’t produce good, fast results.

    Private corporations usually lead to good results, competition(Usa-USSR space race, Intel vs AMD) produces good results.
    Capitalism with private corporations seems to work better than other obsolete systems.
    Scientist in private sector are not there just to observe, study but to work and make it happen, get it done or get fired, it is very competitive field, you need to achive goal fast, find a way to do it.

    Samsung, Apple, AMD, Intel, Tesla, Spacex they manufactured modern phones, notebooks, processors, electric cars, rockets not some international mega project.

    Fusion is close, I can almost smell it, so little money in private fusion sector and still good progress. So much better magnets, better lasers, better computer algoritms, lots of different ways to do it, but serious lack of invested money.

    I see much more rationale in investing money in nuclear fusion than building all that trillion dollar solar, wind or just old school coal, gas plants.
    Seems much more rational long term decision to invest money in fusion than building all that solar, wind.

  12. I do tend to agree with that; On Earth, or Mars, or several other locations in the Solar system, hydrothermal ore bodies have concentrated fissile or fertile elements to useful concentrations, and in those places fission is a perfectly practical source of power, and enormously easier to pull off than fusion.

    But, as we get out into the solar system, we will frequently be going places where you can’t just dig up Uranium or Thorium. But hydrogen is practically everywhere.

    So, yes, long term and off Earth, fusion would be extremely useful. I still tend to doubt it will be steady state fusion, though.

  13. That is probably part of the reason people are so obsessed with it, the sheer challenge.

    Fission is great, but it is dying in the west. Propaganda poisoning people against it.

  14. they been saying they are 10-20 years ways from net energy gain every year for the 50 years for every fusion related research project…

  15. To get it running steady state, you need to maintain crazy high temperatures, in a plasma that doesn’t want to remain together, it’s busy trying to explode. And because it’s HOT, and radiation is the 4th power of temperature, it’s radiating away the heat energy like mad, cooling down. To minimize this, because lighter elements radiate less, you have to keep the fuel really pure, even a little bit of contamination and the heat you need to get the reaction going radiates away.

    So you’ve got this squirming mass of plasma that’s desperately trying to expand and cool, and you need to get it hot enough and dense enough to react at a decent rate, while keeping it remarkably pure, and you can’t touch it directly, you have to manipulate it with magnetic fields. And nobody has gotten this to work yet, in a human lifetime.

    Because it’s HARD. Enormously harder than fission.

  16. No, it IS nature. Fission is just easier than fusion. At one time, millions of years ago, when the percentage of U235 in ore bodies was higher, they would sometimes go critical on their own, and run as nuclear fission reactors. Without the slightest human intervention.

    Well, now, because the ratios of the isotopes have shifted, (Because U235 has a shorter half life.) you can’t do fission with natural isotopic ratios. You have to enrich something, the fuel, or maybe the hydrogen. But fission is still just crazy easy to pull off once you do that. Which is why it was just a few years from the realization that it could be done, to power going out into the grid. It was just that easy. All the complexity is in managing the radiation and byproducts, since humans don’t do so well in really high radiation environments.

    Fusion is hard. It requires crazy high temperatures to pull off. To the point where the first fusion bombs needed fission bombs just to compress and heat the fuel, no conventional process was energetic enough.

    And the bombs only fuse for microseconds, and then the reaction cuts off, because the heat and pressure disassemble the bomb.


  17. All the money the US could put into molten salt reactors just 10 years ago instead of this white elephant and we could have multiple competing designs ready for full scale production. This is a dead end that is meant to show that ‘something” is being done so that the use of oil can continue until as much profit as possible can be pumped out of the ground. Congress is controlled by oil/pharma/financial. In the meant time Indonesia will have the first molten salt reactors up and running unless seal team 6 is sent in to sabotage it.

  18. Why governements are willing to fund this, but won’t put any real money into non sodium cooled fourth generation fission plant research is beyond me.

  19. Flying car has been around since Vietnam war. A chain of reasons, starting with its inability to pilot itself, caused its limited production, high capital and operating costs, limited use and stagnation of development. Now that is changing.
    Fusion was never really funded, hence no fusion. Google pictures “fusion never”.

  20. Putting this in context: The first thermonuclear bomb successfully exploded 7 years before I was born. I might still be alive in 2039, but the actuarial tables are not promising.

    A plasma physicist could have been born after fusion had successfully been accomplished in bombs, grow up, live a full, productive life, and die at advanced age surrounded by his grand children, never to see a working fusion reactor. Isn’t that depressing?

    By contrast, a physicist could have been born on the day of the first fission bomb test, and would have still been in middle school when the first fission power plant went online.

    Nature is trying to tell us something, and, BOY, are we refusing to listen.

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