Wendelstein 7-X Fusion Reactor Produces Its First Flash of Hydrogen Plasma (gizmag.com) 98
Zothecula writes: Experimentation with Germany's newest fusion reactor is beginning to heat up, to temperatures of around 80 million degrees Celsius, to be precise. Having fired up the Wendelstein 7-X to produce helium plasma late last year, researchers have built on their early success to generate its first hydrogen plasma, an event they say begins the true scientific operation of the world's largest fusion stellarator.
This is completely awesome (Score:5, Insightful)
Re:This is completely awesome (Score:4, Insightful)
Now all they need to do is put out more energy than they are putting in and we can call it generation.
Re:This is completely awesome (Score:5, Informative)
They aren't intending to generate energy with this reactor; the goal is to sustain plasma at temperatures high enough to eventually get to fusion. The article says they are at 80 million deg C, which is about 7 keV. They need to get to 14 keV for a D-T reaction (look at the minimum for the Lawson Criterion [wikipedia.org]) . That's excellent work, and if they can sustain it for thirty minutes, even better. When they are done, the design will be proven and then they can do the harder problem of building a reactor that can withstand the neutrons and recover the heat for a secondary cycle.
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couldn't have said it better, just to imagine an energy independent world boggles the mind.
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So it should. How could that ever happen?
Re:This is completely awesome (Score:4, Insightful)
There will never be an "energy independent world". But what one can accomplish is of course highly dependent on how much energy can be provided for a given amount of money (where the concept of "money" is basically an IOU for human labour... all costs, eventually, trace back to human labour)
Of course, cheap energy costs can have disadvantages... it all depends on how we choose to use it. For example, with our greater ability to "make things", it would be quite possible that mining would dramatically increase. On the other hand, we could take a more modest quality of living improvement and dedicate more resources toward recycling and living with lower environmental footprints - even using the energy to drastically reduce our footprint (such as intensive light-driven grow ops, freeing up farmland). It all depends on the choices we make as a society.
All of that said... this is way premature. We don't even know that this sort of technology will - anytime in the remotely near future - prove to even beat current sources of electricity on price, let alone dramatically outcompete them. One can hope, however.
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"Make things" is the limit, not energy. There are limits to resources, energy is just one component of the resource tree.
Recycling becomes key. And with nearly endless energy, recycling becomes a non-issue, allowing for re-purposing of "used" resources.
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Please, you won't get an energy independent world. You'll have patent holders demanding $1 trillion dollars to power your country. And the distribution companies. And of course the competing distribution companies people will open up to allow for false competition and preventing a natural monopoly.
It's a nice idea, but if you think the world is suddenly going to become a place with unlimited free power, you're sorely missing how badly the corporations will fight to stop that from ever happening.
I mean, t
Re:This is completely awesome (Score:4, Insightful)
One problem for the "evil cartel" Patents are only good for 20 years and even if the energy itself is free maintenance of the power lines and distribution equipment costs money.
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Nothing a Sonny Bono act for certain energy patents can't fix...
Re:This is completely awesome (Score:5, Insightful)
* Virtually free & unlimited fuel.
Now we count some of the impediments:
* The machine to create fusion needs to be meticulously manufactured.
* Infrastructure to distribute the power needs to be built and maintained.
* The very best fusion reaction we currently know about ( p + B ) still generates side-reactions that produce Neutrons. There will be radioactive waste to deal with.
* Neutron flux means that the difficult to manufacture machine will need ongoing maintenance.
* The lack of a viable mass-scale superconductor means that many such fusion plants will be needed.
Neither of these lists are complete, obviously. But I feel that they do an OK job to demonstrate the point.
Re:This is completely awesome (Score:5, Informative)
Interestingly enough, for d-t fusion, the neutrons are not an unwanted waste product, but actually essential. Tritium doesn't grow on trees, you have to make it. And more importantly, d-t fusion only gives off one neutron, and it takes one neutron captured by 6Li to breed 1 tritium (you can also make tritium from 7Li bombardment and not consume the neutron, but due to the cross sections and energies involved its usually not as interesting). So if you use one neutron to make the fuel that produces one neutron, and you can't capture 100% of the neutrons, you're in trouble! You get around this by using a lithium-beryllium blanket, as beryllium is a good neutron "multiplier" (capturing one high energy neutron and yielding two lower energy neutrons). It's also rare, expensive as heck and its dusts are highly toxic, but it's consumed at a tiny rate, so it's mainly just an initial cost (heavy elements like lead can also be used as multipliers but they're not very effective in this context, their cross sections don't extend down as far as beryllium and their (n, Xn) reactions where X>2 don't make up for it). So basically, while you lose some neutrons to unwanted reactions, you overall end up producing enough to produce enough tritium for your reactor to consume. The key point is, you want the neutrons to be hitting your reactor, they're doing you a service ;)
There will of course be unwanted neutron captures, but when you engineer it you're choosing specifically what materials are going to be bombarded, so you can pick materials with low neutron capture cross sections and which capture to isotopes that are either stable or have short half lives. Concrete is great for how cheap it is (light elements in general are, and concrete is mostly made of light stuff). As far as metals go, aluminum is great where heat loads or mechanical stresses aren't excessive. Beryllium is even better, as well as stronger and lighter... but see the aforementioned issues with it. Steel is "okay", usually fine if you're careful about what you alloy it with. You generally want to avoid titanium. Graphite is superb if you run it hot enough (otherwise you risk Wigner energy problems). Composites likewise, although they're more temperature limited. Most common ceramics are made of light elements, which makes them very good to use, although those with heavy elements (like tungsten carbide) should be avoided. Tungsten in general should be avoided unless necessary. Some ceramics like boron carbide/nitride are highly heat and corrosion tolerant, high compressive strength, huge neutron absorbers and don't yield dangerous byproducts, which lets them fit multiple roles at once - so long as there's little tensile or shear stresses. In some cases you may want more of a neutron "window", wherein things like zirconium or lead would be good - particularly specific isotopes of them if you're willing to pay for enrichment. It all depends on the operating environment and geometry.
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Fusion is clean energy, not necessarily cheap. It is a replacement for shortage and (nowadays) pollution of fossil fuels, not anything else.
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At this rate, I wonder if fusion will be able to compete with renewables by the time it's made practical.
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The theoretical limits how much wind/solar we can produce are way higher than we need. They either don't need any special supplies to manufacture, or these special supplies can be substituted by other wide-spread supplies without significant cost increase. E.g. many wind turbines use neodymium but newer giant wind turbines don't use permanent magnets and don't need neodymium. You can scale it as much as you want.
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Give it time.
The world of unicorns and rainbows is thousands, perhaps tens of thousands, years of human cultural and physical evolution away. But I believe if we don't poison or otherwise kill ourselves, we have a shot at it.
It took 250,000 years (an eye-blink in evolutionary* time) to develop the forebrain. We've only been using it for about 40K years, and only really beginning to understand it in the last maybe 200 years.
* just don't fucking start with the "no evolution" horseshit, OK? Go back to Prairie
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A trillion dollars to power the US for patents until they run out is cheap. But stuff doesn't magically appear. Either government pays for research or private people do, and the lion's share of invention is the latter.
So better to have new stuff even if costly for a bit, than have it years later, or never.
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Don't worry patents only last for 20 years, and hydrogen fusion has been 30 years away for the last 50! Now I'm off to download the designs for one of those 200MPG carburetors that the oil companies bought up 20 years ago.
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I wish them good luck but they are a long way (and several difficult problems) from generating energy.
Reminds me of the early hype for fission reactors... "Too cheap to meter" which turns out to mean "Too expensive to matter"
Meanwhile, in New Jersey... (Score:1)
https://m.youtube.com/watch?v=R0PYe-4090g
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https://m.youtube.com/watch?v=R0PYe-4090g
Hmm...what is that?
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Presumably they are implying that nuclear fusion is a fraud based on pseudoscience?
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LOL ... wait ... but ... but ... the Sun. For the love of god, man ... The Sun.
Now, something we can build and control and get perpetual free energy? Well, I'm less convinced of that.
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sunfire / in my stellerator / makes me... happy? (Score:4, Interesting)
So I've read the Wikipedia articles on the 7-X and on stellarators in general, but I'm not a physicist.
Can someone knowledgeable tell me how to feel about this? Does this represent meaningful progress toward fusion power? If so, how meaningful? Is fusion still 50 years away, or are we down to 49 now?
Re:sunfire / in my stellerator / makes me... happy (Score:4, Informative)
You should feel whatever you feel, unless you're a robot, in which case: /apply feeling hopeful.
Part of the fusion problem is keeping the hydrogen confined in the plasma. A stellator does this by shaping the magnetic field in such a way that the plasma twists and constricts itself. So instead of constraining a moving plasma, the moving plasma constrains itself.
This requires a precise shaping of the magnetic field via superconducting magnets, and the design of these has only recently become possible with advanced calculations on supercomputers.
So this is a test run of a new kind of fusion reactor. If it works, it will change the world. And so far so good, but we won't know until it works until all following tests succeed.
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Re:sunfire / in my stellerator / makes me... happy (Score:5, Interesting)
The "50 years away" stuff is a really unfair criticism. The amount of progress that's occurred in the past several decades is many orders of magnitude - JT-60 has even gotten to Q=1.25, which means they were getting 25% more power out than they were putting in to maintain the reactor in steady-state operation.
Part of the reason that this concept got started was because of a big mistake early on with the ZETA program. Unbeknownst to them, A) heavy electron bombardment of their detectors was leading to false spectral shift readings, making them think that the temperature was much hotter than it was, and B) there was a possible method to create neutrons that they were unaware could be significant - heavy localized acceleration of ions causing spallation impacts. The unfortunate part was, by coincidence, (B) happened to produce roughly the amount of neutrons that would be expected by (A). So they thought that they were just a short step away from a viable fusion reactor, when in reality they weren't even close. Due to the more primitive technology at the time, not only did they not have detailed computer models that could have warned them to expect the neutrons, but they also didn't have a convenient way to measure neutron energies (it was this that later proved their early conclusions wrong). Their lack of computer models also meant that they were unaware of how much of a problem drift would be.
It's a very different situation today. There's really no question that we can viably produce fusion power today. The real question hanging over our heads is, what is it going to cost? How can we engineer a system to produce power affordably? And that's the real question that's going to take a lot of work to figure out. One thing is for sure, though: the higher the magnetic fields you can get for a given cost, the vastly easier it becomes. And these new high temperature superconductor tapes could push us leaps and bounds even beyond ITER, whether you go with a stellerator, a more traditional tokamak, or really anything else that employs magnetic fields. It's very encouraging for the field to see a route that already looked to be on a positive path get such a "bonus".
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Re:sunfire / in my stellerator / makes me... happy (Score:4, Informative)
Re:sunfire / in my stellerator / makes me... happy (Score:5, Informative)
As an engineer working in the fusion field, I would not agree it's quite so rosy a picture. *Lots* of issues need to be solved technologically, although I agree with you the physics side of Tokamaks is relatively understood. I.e. it would be a huge shocker if ITER didn't produce the power expected. Tokamaks are however very unreliable with stability, and whether or not these can be controlled and mitigated enough for reliable power production remains to be seen. Further, going from ITER to DEMO is like launching a rocket to space vs. going to the moon; the high energy neutron flux from a fusion reactor will centimeters of the first wall to powder. Getting enough lithium around the wall for tritium breeding and heat removal for a steam cycle is very difficult.
In the end, it's all economics as you say. I can't imagine with the present state of technology a viable commercial fusion reactor online until past 2100. ITER will be ~2030, DEMO ~2070 if ITER cost/is any clue. Say you're making a decision for a company - would you rather spend $20 billion dollars on a very finicky tokamak fusion reactor with tremendous maintenance costs (tritium recycling, lithium management, disruption and instability mitigation systems, etc.), or a gen III or IV nuclear reactor - perhaps a thorium molten salt reactor - that produces the same power reliably for a small fraction of the cost?
Commercial fusion will happen eventually, but in my opinion not without tremendous advances in materials science and superconducting magnets. One can imagine with clever first wall materials and >20 T fields using advanced BSCCO superconducting materials (or other) a reactor might become as affordable as a fission reactor of the same power output. Contrary to what fusion researchers will have you believe, fusion will always be in economic competition with fission.
This PDF sums it up pretty nicely: http://www.askmar.com/Robert%20Bussard/The%20Trouble%20With%20Fusion.pdf
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WTF is this? A knowledgeable reply containing a citation to a scholarly article?
Has Slashdot come to THIS?
I'm taking my sockpuppet and going home.
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The plasma facing material faces a flux of 1 neutron per 17,6Mev. By contrast, nuclear fuel cladding faces a flux of ~2,5 neutrons per 202,5 Mev, or 1 per 81 MeV. It's certainly higher, but it's not a whole different ballpark. And yes, you're dealing with higher energy neutrons but in a way that can help you - you've often got lower cross sections (for example [bnl.gov]), and in most cases you want the first wall to just let neutrons past.
There's a number of materials with acceptable properties. Graphite is fine
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Hmm, thought... and honestly, I haven't kept up on fusion designs as much as I should have... but has there been any look into ionic liquids as a liquid diverter concept? In particular I'm thinking lithium or beryllium salts. They're vacuum-compatible, they should resist sputtering, they're basically part of your breeding blanket that you need already... just large amounts, flowing, and exposed. Do you know if there's been any work on this?
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The plasma facing material faces a flux of 1 neutron per 17,6Mev. By contrast, nuclear fuel cladding faces a flux of ~2,5 neutrons per 202,5 Mev, or 1 per 81 MeV. It's certainly higher, but it's not a whole different ballpark.
The fusion situation is worse, because the total neutron flux is still much higher for a given unit of area and volume. Higher neutron energy doesn't mean messier collisions for the most part, and that energy just gets spread out over a larger volume.
Regardless, the total neutron flux is higher in a fusion reactor. A fission reactor might see on the order of 10^23 neutrons per square meter over the entire 40-50 year lifespan. Fusion reactors are estimated to be on the order of 10^26 per square meter per
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How can you make generalized statements like that? Cross sections vary by many orders of magnitude Fission reactors are generally made of steel, which is hardly setting any records in terms of low cross sections. The smaller the reactor, the less material you have to replace, and the more expensiv
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How can you make generalized statements like that? Cross sections vary by many orders of magnitude
Fast neutron cross scattering sections in the couple MeV range barely vary over more than the range of 1-10 barns. Fe56 is about 4 barn over this range. C12 drops off from about 3 barns to 2 barn, hydrogen from 4 to 1 barns, Be9 from 7 to 2, but mostly around 3 to 2.
And being "displaced" is not a fundamental universal material property effect, it depends on how the material responds to radiation damage, which varies greatly.
It is a measure of the environment, and illustrates that fusion reactor walls are in a different ball park than fission reactors. You can't look at fission reactors and say those materials will be fine under a couple orders of magnitude more
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1-10 barns is, of course, by definition, an order of magnitude. There is a massive difference between 10 barns and 1 barn. Tenfold, to be precise. ;)
More to the point, you can't just combine all cross sections like that. The energy imparted from an elastic collision isn't the same as from an inelastic collsiion, which isn't the same as an (n, gamma), and so forth. Elastic collisions are parti
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How can we engineer a system to produce power affordably?
Ask Elon to do it!
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It's still more like 50 years towards fusion. The Wendelstein was only built to investigate how well stellarators can confine plasma over a long period of time. No fusion will actually happen in this facility.
A stellarator is one of the three most promising plasma confinement methods:
* Magnetic confinement by means of the Lorentz force. There are actually two ways to achieve this:
- Confinement with toroidal/poloidal coils and injection of an electrical current into the plasma. This is
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The Wendelstein was only built to investigate how well stellarators can confine plasma over a long period of time. No fusion will actually happen in this facility.
Incorrect. The Wendelstein will reach pressures and temperatures necessary for fusion. Fusion will occur in it unless something seriously goes wrong. What won't happen is electricity generation.
You are correct on the 50 years though - the director of the Wendelstein mentioned that there will need to be another generation of test systems before power generation will be able to be seriously considered.
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Stellarator? Sounds like something Dr. Doofenschmirtz [wikia.com] would build.
"Behold, Perry the Platypus! My Stellarator! It will make anyone it zaps think they are Marlon Brando in 'A Streetcar Named Desire'! [youtube.com]"
Precise? (Score:3)
Sorry, what definition of precise are we using here?
I'll be glad when we get through this shakedown period of falling editorial quality by ... well, by timothy, actually.
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It is a funny sequence of words, but in context it doesn't seem wrong. It says at first 'heating up', then '80 million degrees' which is more precise than 'hot'. It sounds a tad cheesy to me doing the rather uninspired play of words, but not incorrect usage.
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No, "more accurate" would be correct ... an exact temperature would be "precise".
That's kinda-precise-ish in a vague hand-wavy kind of way. Kind of the opposite of "precise".
"around 80 million degrees Celsius, to be precise" is sure as hell NOT precise.
That could be +- 5 million degrees and still be "around".
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'more precise' would have been better, but 'precise' by itself is a very relative term. There's no set number of significant figures that can be considered 'precise' versus 'not precise' in absolute terms. Having 3 significant figures may be precise in some context, even though in another you could have 6.
In this case, the starting point is no significant figures, increasing to 1 significant figure is precise (by comparison).
Both values may be considered 'accurate'. Hot and 80 million degrees are both ac
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Precisely.
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Hallelujah! (Score:2)
Fusion energy is impractical (Score:4, Informative)
As a former program officer for the Office of Fusion Energy, US Department of Energy I can assure you even if the Stellarator "works", it will not be a practical source of power. The complex engineering and cost make harvesting energy from fusion impractical.
I could fill a page on enumerating them. For one -- fast neutrons can destroy any material known. No one has come up with a design for the the first wall that captures the neutrons and energy.
The old quip is "Fusion has been 25 years in the future for the last 50 years.
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You don't need to be a program officer to know that, they staff of the 7-X say that themselves, there is no expectation it will be used for power generation. The 7-X is a machine for science.
Re:Fusion energy is impractical (Score:5, Interesting)
Fast neutrons can impact any isotope and destroy it in that regard, but that says nothing about the long-term structural stability of the bulk material. Different materials have different annealing properties. More to the point, slow neutrons can do the same thing, just in a different manner (that is, (n, gamma), instead of (n, random-ions-and-neutrons)). Fast neutrons are overall more damaging (and of course more penetrating... although we're not talking about spallation neutrons here with energies up into the GeVs, we're only talking 14,1 MeV) - but they're not some sort of whole different ball game. I am, of course, assuming you're talking about structural issues. If you're talking about from the perspective of how radioactive it will become, tell me, how hot does beryllium get under heavy bombardment? Boron carbide? Graphite? I could keep going. In fact, I did, further up the thread.
There are many reasons to complain about various designs, but your over-generalized statement is anything but some kind of universal rule. And really, the sort of flexibility of materials that fusion allows versus fission more than compensates for having to deal with higher neutron energies.
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You can't control where the neutrons go since they aren't contained by the magnetic fields the way the plasma is. Some of the neutrons will stay within the reactor and propagate the reaction and others will exit the containment vessel. And my understanding is that the neutrons leaving containment are necessary too, since they contain energy which can be collected and turned into electricity.
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The same applies to slow neutrons, so....? Your average 14,1 MeV neutron is most likely to inelastic scatter down to the point where more exotic reactions than (n, gamma) are basically impossible (excepting a few specific cases, like 6Li(n,t)4He - again, not dangerous). Only a small percentage of your 14,1MeV neutrons (depending on the material they're passing through) have a chance
familiar (Score:4, Funny)
Germany's newest fusion reactor is beginning to heat up, to temperatures of around 80 million degrees Celsius
80 million Celsius? That's on par with a Hot Pocket that's been microwaved too long. I wonder if they are using Hot Pocket technology. ;)
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Well, it's the more generalized problem of Melted Pizza Cheese.
That freshly delivered pie will strip all the flesh from the roof of your mouth, and you should probably leave it to sit for a few minutes. You won't, but you should.
Cheese forms a super-heated semi-fluid capable of delivering FAR more heat than its thermal mass should allow.
You could cauterize wounds with fresh melted cheese from pizza.
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I think he's recommending military applications of pizza technology. It's a workable idea. Leave serverely overheated hot pockets on the enemy battlefield, enemy soldiers can't resist picking them up and biting into them once the outer crust cools (while the interior is still as hot as the inside of an operating fusion reactor), and then this happens. [giphy.com]
It'll work until new treaties outlaw the use of hot pocket weapons as a war crime.
Even then, the technology could help medics cauterize wounds on the field. Du
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Thank You (Score:1)
That made me laugh.
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Germany migrates away from nuclear fission power, yes. But Germany is still funding science, and that not only if there is "return on investment" to be expected before the next elections.
Might be that fusion power won't be required right when it becomes feasible. But humankind might be happy to have it at hand during the next ice age.
So close. (Score:2)