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Wendelstein 7-X Fusion Reactor Produces Its First Flash of Hydrogen Plasma (gizmag.com)
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.
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?
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, that would be communism, and communism would be evil.
Don't get me wrong, this is completely awesome. I just don't think it would ever be allowed to undercut a model in which a series of middlemen charge you their cut to deliver something which they get for free.
You don't maintain shareholder value giving stuff away for free, and it's ALL about shareholder value.
And there's way too many entities who will want to get their beak wet to think you'll see much different than you see now.
Lost at C:>. Found at C.
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".
It's times like this I wish I had a friend named 'The Professor'.
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.
It's times like this I wish I had a friend named 'The Professor'.