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[dupe] Germany is turning on its monster stellarator (businessinsider.my)
258 points by radiorental on Nov 2, 2015 | hide | past | favorite | 129 comments

I find watching the assembly of these ultra-high tech machines to be super inspiring. It gives me all kinds of warm fuzzies to see what we're able to do if we put our mind to it.

Mostly it's inspiring because most people sit back and say "It can't be done, it's impossible" or "wow, they must have had a shit ton of luck to get this out of the door" instead of looking for solutions or ways to circumvent or exploit the million little problems along the way that seek to obstruct the endgame.

Kudos to these guys for sticking at it long enough and persevering to achieve their vision.

I guess different people see different things in such projects. What I see:

  - *massive* success of coordination and cooperation
  - illustration of potential humanity has
  - that careful and methodical approach can make even such monsters of recursive complexity work
Luck does not enter the picture. Will and determination do though.

You'd be surprised how often will and determination is more of a factor of success than luck.

[Your level of surprise may vary]

My inspiration from massive science projects is more like: "With that in mind, debugging this 1500-line function is nothing!"

Dude... refactor that shit. There is no place in today's development world that a 1500 line function is okay :P

Not all functions are refactorable. A 'purely hypothetical' scenario: a numeric routine of several klocs on length, that takes in 20 parameters with 1-3 letter obscure variable names, was written 30 years ago in fortran, was f2c:d 20 years ago into c and has been doing it's 'stuff' correctly ever since somewhere in the bottom of mission critical code in a codebase of millions of lines. Commercial codebase. Only a handful of developers. Management expect new features and expedient, safe bugfixes that do not change end user functionality.

The scenario you describe is a disaster waiting to happen.

Refactor it, preferably yesterday - but make a "shadow deploy". For each set of input / output parameters run both functions and compare them. If they differ, use the old one and go back to figuring out where it went wrong. After some time you can be quite sure that the new clean function works as it should - then you just switch.

I am not sure the above idea is mentioned by Michael Feathers in his amaze book "Working Effectively with Legacy Code" but it is a great idea, and combined with the things that Michael does cover will do you a lot of good!


That's actually simple. All you need is to npm yeoman to generate a proper skeleton for grunt and gulp to work using Mockito.js, C2F.js and Fortran.js, then you can auto-generate unit tests that will be paralelly distributed over AWS.

More seriously though, the kind of code you described will be what I imagine the first subject of study of the software archeology field in the future.


Indeed. It will save you from needing inspiration to debug it as well. It's much less cognitive load when you break those crazy things into understandable parts.

The potential speedup on those old F2C routines is amazing. The ability to use much more memory, understand cache levels, etc. have a huge impact.

When was the last time you've seen pure Assembly? Also, JavaScript namespacing shenanigans & stuff... :P.

I make 3rd party/unsanctioned mods for video games in my free time, which involves plenty of Assembly :)

It's a legacy system developed by someone who is lucky he lives 4300 miles away!

I've been working at the system to free it from that subsystem with an eventual replacement. There are all kinds of single-letter variables and Russian words, refactoring wouldn't be economical or sane.

the first video claims a magnetic field strength of 2.5 Tesla(o) roughly that of an MRI(i)

can anyone speak to sort of considerations that lead to this value? 2.5T seems insignificant considering the events it will be confining

how sensitive is the field to magnetic interactions outside of the device?

(o) https://youtu.be/lyqt6u5_sHA?t=301 (i) https://en.wikipedia.org/wiki/Tesla_(unit)#Examples

Steady magnets can't get much stronger than that. The very strongest steady magnets, purpose built, are in the 40-70 tesla range. I believe the limit is set by the break down of normal matter. Higher field strengths can be achieved, but only for fractions of a second and are general destructive.

Imploding coils. This stuff gets me every time I see it - chills down the spine. You can induce a field in the MEGAtesla range for an infintesimal amount of time. Take a copper (or superconductor, if you're feeling ballsy) coil, run a huge current through it from your enormous capacitor bank, set off a wad of high explosive surrounding the apparatus - the near-instantaneous collapse of the conductor causes the field within to become absolutely enormous - and equally importantly the Ts-1 - i.e. the rate of change of the field - again, you can induce enormous currents outside of the apparatus through induction.

This technique is mostly used in solid state and, surprise surprise, fusion experiments. Oh, and you can make an EM bomb if you make a big enough one, and wipe out a city's electronic infrastructure in a microsecond. https://en.wikipedia.org/wiki/Explosively_pumped_flux_compre...

That's part of the beauty of the stellarator design - you need a comparatively weak (2.5T is still an unholy field) field to maintain containment.

Probably for each magnet, of which there are fifty.

And considering these devices are heavily shielded, I would doubt there would be much interaction outside.

I'm glad that Germany now has the option of stellarating the monsters they capture.

EDIT: On reading further, it turns out I may have misinterpreted the article.

Even better if they make a portable version and call it Mr. Fusion

I once did an internship at the MPI in Garching and had the opportunity to visit the Stellarator. Although it looks much less spectacular with all the coils hidden in their housing it is still an incredibly impressive machine with an audacious design.

Today the numerical effort required for realizing it might seem not very impressive given the technological capabilities that we have, but you have to take into account that the first version (Wendelstein 7-AS) was built in the 1980s already.

That said I really hope that the experiment confirms the viability of this design and its (potential) superiority compared to the classical Tokamak fusion chamber.

I have no doubt that a design that goes with the physics (instead of going against it like Tokamaks do) is going to yield great results, however I hope something comes out if it that will also allow for viable Tokamaks. Stellarators are hellishly complex and expensive.

> Stellarators are hellishly complex and expensive.

True but that is largely true of the first of anything complex and expensive since it's Development Costs + Construction costs / 1 until they build another.

Can you explain what you mean by tokamaks "going against the physics"?

Tokamaks need, to contain the plasma, a continuously changing magnetic field. To create a continuously changing magnetic field, you need to continuously increase or decrease the current.

The issue is that you can not turn up the current more than a maximum level, and you have to keep the direction the same (so you can’t switch between turning off and on).

Stellerators instead solve this with complex geometry and the plasma creating its own continously changing magnetic field.

> Tokamaks need, to contain the plasma, a continuously changing magnetic field

Do you have a citation for this claim?

I could source one from German Wikipedia, but english wikipedia does not seem to have that information.

You might be able to find some sources when you search for the reasons of Tokamaks pulsed usage.

A tokamak is basically an AC transformer, with the plasma acting as one of the windings.

So far as I understand it (arm chair physicist), Stellerators "shape" the plasma in a "natural" way, Tokamaks force it into a more "unnatural" shape - like trying to put a beach ball [plasma] into a box [torus].

If I misunderstand it disregard my comment entirely, although I'd like to know why.

Here's how I understand it:

- The simplest closed magnetic configuration is a torus. You can't smoothly "comb a hairy ball", but you can comb a hairy torus.

- For a toroidal plasma to be stable, it needs magnetic field components both the "long way" around (toroidal), and the "short way" around (poloidal).

- The tokamak generates the poloidal field from a current within the plasma, whereas the stellerator imposes that component with external magnets.

So you could make a "natural" argument either way, and I was asking the grandparent in what sense the stellerator is more "natural".

Well, if this one works, they just need to copy, it, right? I mean in the end, you really only need one viable design.

This is likely to be more important, for much less expenditure, than ITER.

Edit: to add some additional context, the main problem with fusion reactors is confinement time and plasma stability. The general idea of a fusion power plant using magnetic confinement is that a gas is turned into plasma, confined magnetically, and heated until it can undergo significant fusion reactions. There are two core problems to creating fusion plasmas that could potentially produce power. One is pumping the plasma up to conditions that enable self-sustaining fusion by maintaining a high enough temperature from balancing the heat losses in the plasma against the heat gains from fusion reactions. The other is producing more energy from fusion reactions than was put into heating and containing the plasma. The longer the fusion plasma is contained the longer it has to continue fusion reactions and producing energy.

Tokamaks are easy to build but have a fatal flaw in that they have high plasma current, which makes them difficult to control with very unstable plasmas. Stellarators are vastly more difficult to build but they don't rely on currents in the plasma itself, which offers the potential for vastly longer confinement times.

This is wrong comparison.

Wendelstein 7-X is small early experimental reactor for testing stellator geometry for reactor. Research questions are similar to where JET (the largest working tokamak today) was 30 years ago. Stellator is more complex design but promises inherently stable containment.

ITER is solving different questions. ITER solves engineering problems for full-scale electricity-producing reactor that would be practical to build and operate. JET studied containment in Tokamaks. ITER is the last step before first industrial fusion reactor design DEMO (Demonstration Power Plant).

There is also lots of technical overlap of course. Vacuum vessels, cooling, magnets, breeder blankets, etc. ITER is developing these for industrial-scale reactor, even for stellator.

This is exactly right. Regardless of which technology proves viable first, the reactors will have their parts built in the same factories.

the key difference is ITER is designed to be net-energy-positive, while this will generate precisely 0 W of energy, if it works (which I hope it does!)

It's more appropriate I think to compare W7X to JET, not ITER. They're not trying to break even on fusion with W7X.

> The key to a successful nuclear reactor of any kind is to generate, confine, and control a blob of super-heated matter, called a plasma — a gas that has reached temperatures of more than 180 million degrees Fahrenheit.

Um, what? I'm about to pass a nuclear fission plant on my way to work, and I surely hope there are no plasmas in that.

AKA, they mean fusion reactor.

Nucleons are reacting. It's most definitely a nuclear reactor of some type.

nuclear reactor of any kind

They're not disputing the nuclear term, but fission vs. fusion.

Ding ding ding.

Also, hello from Indian Point, Buchanan, NY! I can see a containment dome as I write this.

Next up on my Snake Plisskin-esque commute is literally going through Sing Sing prison: https://www.google.com/maps/@41.1506265,-73.8700067,613m/dat... (those train tracks are the Metro North Hudson line, among other things)

"Designed in Hell" - really? Goddamn, I hate modern media outlets...

They meant to say north east Germany, it's a minor typo.

Hell, CA; Hell, MI; Hell, AZ; Hell, Norway; or Hell, Netherlands?

Hell, the Devil's playground... because it looks strange.

What kind of association does that make in people's minds, they already think nuclear = death...

Worth pointing out that this phrase was the title of a linked 3rd party YouTube video, not from Business Insider Malaysia who did a reasonably decent job on the article.

Yeah, nothing against the article, actually, but the video is from Science Mag - you'd think they'd be more professional...

Assuming these experiments work as desired and this reactor can produce more energy than it takes in, how long will it be (roughly) until a power plant becomes operational (i.e. connected to the grid) that uses this technology? Years, a decade, many decades?

It's not yet designed to produce net energy – it can't handle the necessary (radioactive) tritium fuel.

Assuming it works as intended, the next step would be a research reactor that can, that would be a pilot project to generate net energy which could be connected to the grid (probably more for symbolic reasons at that point…) and breed tritium for further reactors.

Then we can start to plan building actual power plants. So, few decades, as always.

I guess we can still say it will be the most important energy source over the next millennium...

If the only reason they won't be net positive is that they're not using tritium, that would be a huge win.

Here's a comment on that by Prof. Dr. Sibylle Günter, Max-Plank-Institut für Plasmaphysik (In German): https://www.youtube.com/watch?v=sweAVoaVB34

The current schedule is to have an operational power plant in 2050.

For those who don't speak German, that's the schedule for 2050: ITER is supposed to show by 2027 a successful result to produce more energy than put in. Then they want to rework the design and start building an actual power plant around 2035, allow 10 years of construction, with being connected to the grid around 2050.

5-10 years is the classic naive/huckster estimate.

30-50 years is the respectable man's "I have no idea" estimate for anything.

We used to build cathedrals that took 3 generations of masons. Imagine working on a design that your granddaughter would see the launch of...

Look at the Sagrada Familia in Barcelona. They started building in the 1880s, and it's still going on.

Considering that this is 9 years late on the build phase... I have no idea. By that fact alone I'd guess decades. But who knows where resources will flow, and what genius lies around the corner!

Personally, I'd bet on other technologies being more cost effective for power generation in the next 20 years.

Good to see that there is enough money to pursue stellarators while simultaneously working on tokamak designs like ITER.

Well, whichever nation builds the first working Fusion power plant wont know where to put all the money.

How long until NSA and China steal those designs, though? Two...maybe three months? I guess whoever builds it will also have the expertise advantage in dealing with those designs, though, which should give them at least a few years of competitive advantage.

Also, my guess is neither of these "traditional" approaches will work to create actual fusion power. My guess is someone else's out of left field approach that will totally shock the scientific community will be the winner.

To realize a complex design like a Stellator they actually also needed to develop a lot of manufacturing expertise, had to build custom machines for making tools and components etc., I doubt anyone would be able to copy that without significant effort.

It's not like stealing a cookie recipe. Pretty much anything that has even a little bit of complexity can't be "stolen" just by having a blueprint.

I was chatting about this with a friend and there are something like 5 different in production technologies which produce or cause nuclear fusion. Only three I think are aimed at sustainable power generation, but it's still pretty cool.

I hadn't heard of this one before, always interested in fusion news. 3 others I know about are


http://lawrencevilleplasmaphysics.com/ (Focus fusion)


Tri-Alpha is the biggest private effort...about $200 million invested, 30 Ph.Ds, 150 employees. They recently announced they'd achieved stable plasma, the only major milestone left is scaling up the temperature. They think the plasma will get more stable at higher temperatures. Like focus fusion, they're attempting boron fusion.

Helion is similar to Tri-Alpha but with a pulsed design instead of steady state. They have funding from YCombinator. Instead of boron they're shooting for a hybrid D-D/D-He3 fuel cycle (the D-D reaction produces He3). They say only 6% of the energy released would be as neutron radiation.

Sandia's MagLIF project is interesting. According to their computer simulations they can get 100x to 1000x energy gain by preheating a fuel capsule and crushing it in an upgraded Z-Machine. Things are looking good so far.

UW has the Dynomak project, which is fairly similar to tokamak but a lot smaller and cheaper. They need $10 million to test the concept.

Just saw this: "New advances in magnet technology have enabled researchers at MIT to propose a new design for a practical compact tokamak fusion reactor". Plus the usual "10 years away!"...


Thanks! The diagram at the top of that one made more sense than the entire OP article.

Wow - it looks like very Steampunk with all those valves and ports.

Looks more like modern art to me.

This is one of the greatest events in the history of energy research. Really, really hoping that the upcoming results of the machine will at least meet expectations.

A naive question - if this kind of reactors start producing more energy than consuming, what kind of fuel would they need? AFAIK the Sun slowly burns hydrogen into helium. Does it mean that stellarators would only need hydrogen to operate? That would be basically free energy.

Fusion reactors can use different fuels based on how good they are at containing plasma.

Right now, almost all research is directed towards the easiest possible fuel that requires least powerful containment, that is, Tritium (H3) and Deuterium (H2). Deuterium can be separated from water, and Tritium can be bred from Lithium using waste neutrons.

T+D is inexhaustible, but also quite expensive as both separation and neutron breeding are relatively expensive. However, as a fusion reactor consumes tiny amounts of fuel per unit of energy, a T+D reactor could potentially still run profitably.

If we get better at containing plasma, other fuel choices become available. Most important being Boron + Hydrogen, which would be inexhaustible, cheap, and produces minimal neutrons during fusion, making it easier on the equipment.

However, free fuel doesn't mean free energy. The cost of all nuclear power, including current fission power, is utterly dominated by the capital cost of equipment.

Fusion reactors typically use some combination of Deuterium (heavy Hydrogen) and Tritium (super heavy Hydrogen), though sometimes also use Helium-3, Lithium or Boron.

It doesn't say how many watts of power this machine would produce and what is the cost to produce per watt? It would be interesting to compare numbers and see if this machine would ever see mass production in next few decades.

My understanding is that this reactor is just a test to see if this can contain plasma for longer periods of time (from the current 6.5 minutes to a potential 30 minutes). It will not show a net-gain in energy, as it is not designed to produce energy, just a proof of concept.

Zero watt. It's a research reactor. And they don't want to use tritium (which is apparently needed for power generation) because it would cause radiation. And radiation is bad when you want to do research on the reactor. Source: German wikipedia

> And radiation is bad when you want to do research on the reactor.

As in, you want to partially disassemble and tweak the reactor regularly. Neutron activated metals will be radioactive enough after a while, no need to make things worse by adding tritium to the mix.

Probably because it's not a power plant but a research reactor and is not producing electricity.

According to wikipedia :

"The purpose of Wendelstein 7-X is to evaluate the main components of a future fusion reactor built using stellarator technology"

So I'm guessing it can't produce power as it is.

It's a research reactor, it doesn't have power extraction systems, it's all about studying burning plasmas as well as plasma confinement.

That machine looks absolutely beautiful to me, I love the design. It would also be perfect for in movies and computer games :)

When exactly is it turned on?

That was not reported. This is what was reported on Oct. 23rd by sciencemag.org:

"Approval to go ahead is expected from Germany's nuclear regulators by the end of this month"

Tell me that doesn't look like it came straight out of Akira... :)

"Designed in hell" low class.

I'm still waiting on LFTR.

Uranium-fueled molten salt reactors will probably happen first; they'd have the same safety advantages but without the huge extension of fuel supply that you'd get from thorium breeding. Some designs would be more proliferation-resistant than LFTRs. Startups attempting it include Terrestrial Energy, Transatomic, ThorCon, Moltex, and Seaborg.

That's how Germans do it - they keep quiet and just do it. Respect!

You're probably mostly reading English language media, which reports a lot less on German stuff than American and British. Probably if one read Frankfurter Allgemeine, Spiegel and Focus, this would have been popping up there a lot.

Or sometimes they don't do it at all. Just look at Berlin's new airport. Still not open.

Sometimes they keep it very quiet: https://en.wikipedia.org/wiki/Volkswagen_emissions_scandal

No, seriously. All these statements about German character or German mentality should stop. If the last few months haven't taught us anything else, at least it should have taught us that. First, Germans and the German government were praised as reliable in connection with the Grexit (as opposed to the Greeks), then a few months later, a German government owned car producers is caught in what might be the biggest corporate fraud ever.

I wonder if mentality and national traits even exist.

And how did VW handle it?

CEO resigned, 10 board members suspended, all non-management employees (engineers, programmers, etc) have full immunity, even if they worked on the defeat device.

That’s the most honorable reaction one could expect, and it allows to get rid of the issue.

> all non-board employees have full immunity, even if they worked on the defeat device

I'm not trying to pick a fight, but how is that in any way honorable?

Because this defeat device is nothing you should blame on a single engineer, it is clearly a systematic issue, and normal engineers should not be held accountable for actions that the CEO and board forced them to do.

On the other hand it teaches those on the ground that obeying illegal orders is perfectly fine, because, hey, you won't get punished.

It is also the only way you get people ever providing evidence against their boss, as otherwise they'd risk incriminating themselves.

You can support that goal by offering immunity to whistleblowers.

Well, offering immunity to everyone who just followed orders is an important part of doing so. And it makes in this case everything a lot easier.

Offering immunity to everyone who just followed orders is far more drastic than offering immunity specifically only to those who actually takes the step of whistleblowing before the issue becomes known.

The former creates no incentive to be a whistleblower - it just takes away one of the risks of doing so. The latter creates a strong incentive to be the first to report something.

Disobeying those orders would just get you quietly fired.

and yet the "I was only following orders" line of defense should not be very popular anymore, especially in a german context.

It's not a defense. It encourages lower-level employees to come forward with incriminating information about higher-ups, even if if would also incriminate themselves. It's the best way to get them to roll over on their bosses.

The same logic applies to management, wouldn't it? So a middle manager should not be punished, if he incriminates a higher level manager. Until what level is it ok to get a free pass incriminating your boss?

People should be encouraged to come forward _before_ they do something illegal.

If you reward lower level employees for doing it after the fact, the rational thing for them to do is to continue acting illegally, as if the thing blows up they will be bailed out, and if they don't they might still suffer the consequences of it (i.e. get in bad relations with their boss).

I am not saying there is the same level of responsibility, but there should be _some_.

That’s what the CEO of the US branch said.

Those "engineers" were the leading engineer of R&D and the leading engineer of Engine Design. Both board members.

Befehl ist Befehl ;-)

Not to absolve the Germans in any way, but the French, Swedish and US automobile industry was caught with this kind of cheating software 15 years before the Germans. It doesn't seem to be a nationality thing. http://www.transportenvironment.org/publications/cycle-beati...

They do, but they're merely tendencies: You get a wide range of things in any country, unfortunately the world isn't black and white.

>I wonder if mentality and national traits even exist.

Sometimes, but more often they're more propaganda than truth.

And oftentimes the ones rallying other behind said traits are the first ones to ditch them in private. As seen in history again and again. For example during the fall of the roman empire. Except maybe for Cato the younger[0].

[0]: https://en.wikipedia.org/wiki/Cato_the_Younger

Every week I learn something new to admire about Germany.

Or at least its responsible investment behavior by its government.

USA would not build such a thing in today's political climate of nonsense unless it had weapons research possibilities.

Actually, the US invested in both the National Ignition Facility for H-Bomb and Fusion research, and in ITER.

Just because the US invests rarely in civilian research doesn’t mean they never do (compared to military research; compared to other countries they still invest a lot in civilian research)

NIF is weapons research, hence my point.

Congress won't fund a civilian space shuttle anymore but we spend billions for the military to have their own.

Like I said, if it's not about killing people, destroying things and spying on the world (including our own people) we pretty much won't spend money on it anymore here.

Germany did the investment beyond war.


Is that supposed to be a joke?

Besides betraying a rather shallow understanding of history (e.g. implying that "round 1" had the same causes as "round 2"), I do think at this point an American accusing Germans of fascist tendencies and war-mongering is pretty rich, what with the drone wars and the global surveillance and all.

Pretty strange line of reasoning. I'd guess a clean and healthy economy are not exactly typical preconditions for "a round three".

[ED: this was in response to a deleted comment about world war 3 coming...]

I can assure you Germany is not out of trash.

Germany is still years away from 100% renewable. But is actually making progress to there. There's a lot of coal still dug up and burnt for example.

Germany has had lots of immigrants for decades, and things have been mostly peaceful.

The current leader (Angela Merkel) is considered to be from the right, leading a conservative party.

The democracy is one of the most stable around, and many people are anti war.

There are serious issues with the German economy, and the state of the country in general. It's not highly ranked internationally for things like GDP or internet speed.

Whats wrong with its GDP? The PPP per capita is right around Sweden, a little above average for a first world country. Why should it be higher?

I agree that internet should be much better than it currently is though, yet still far from bad. Australias internet made me really sad when lived there... maybe everything feels good in comparison to that.

Actually, the "someone comes in from the right" is already there, the right-national has almost 14% of the population behind it now, with more people being able to "imagine voting for them".

And with them saying things like "Yes, there is a problem with the refugees from Syria, sadly, the concentration camps are currently closed" it’s getting a bit scary.

The AfD [0] has gotten votes mostly from the CDU. But they're still below 7.5% in latest polls from about 3.8% in 2014. The green party even has more than them.

It does seem much of that is a protest against the policies of CDU. These people would rather immigrants freeze it seems.

If an election was called now, then a left coalition would probably get in, since CDU and AfD are unlikely to team up.

[0] http://pollytix.eu/pollytix-german-election-trend

Seriously? One guy (who is not even affiliated with a political party nor has a political office) makes a tasteless comment and suddenly the whole of Germany is supposed to be on the verge of turning fascist again? And even if 25% percent were going far right - there would still be 75% holding other political views. Trust me, Germany is far from going extremist any time soon.

I am not saying we are turning into a fascist country again. Definitely not.

But the right wing terror is getting scary, with dozens of asylum homes being burnt down just this year.

But think of the proportion of wealth / GDP that isn't leaving the country to import oil and natural gas. It makes sense that producing the vast majority of your energy needs yourself would have a significant positive impact on your economy.

Not that the single trite explanation could address the whole of their success, but certainly could account for a 'bump'

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