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Biggest Obstacle of Nuclear Fusion Overcome?
Yetihehe writes "Nuclear fusion could become a more viable energy solution with the discovery of way to prevent super-hot gases from causing damage within reactors. The potential solution, tested at an experimental reactor in San Diego, US, could make the next generation of fusion reactors more efficient, saving hundreds of millions of euros a year."
but I guess it makes me wonder if such a thing would ever be possible? Can a car run purely off of garbage? Or does the fusion process require a more specific substance to begin with, like water or carbon or something?
The first post related to fusion on /. without declaring that cold fusion is only a few months away!
http://religiousfreaks.com/Are that many foriegners being killed annually by fusion? I knew stuff was bad out there, but this is amazin
So, nuclear fusion has finally got serious backing from politicians and the R&D budget to go along with it?
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Hemos, Where did you get this "Biggest Obstacle" from? The researcher didn't claim it in the article, and it isn't true. IANANP, but from what I've heard, the biggest obstacle to nuclear fusion is maintaining the reaction for long periods of time, and doing so with relativly low energy input.
This is a cool development, but unless I read incorrectly it doesn't solve those problems.
Actually, it is about causing damage. The mag field does not 'leak' (implying that the magnetic field becomes somehow compromised); instead, it's overcome. The technique doesn't incerease the mag field's strength, but draws off the cause of the 'bursts'. The end result is that the fusion reactor is damaged less, loses less heat/plasma density, gets better efficiencies, and has to be shut down less often.
Thus saving millions of dollarpounds each year.
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I think maybe you're confused between fusion and fission. Environmentalists generally don't mind fusion, as it is a safe, and very eco-friendly way of producing energy. Which is, you know, what they like.
;-) ) being the second biggest.
Fission, on the other hand.. is problematic. It might be the only viable alternative at the moment (well actually I'm just saying that to not get flamed) but nobody can say it doesn't have its share of problems. Waste being the biggest, safety (yeah yeah I know, pebble reactors, yada yada
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huh... I always thought the biggest obstacle to overcome would be... you know... getting a positive energy return from the damn thing!
-ubuntu others as you would have others ubuntu you.
No, "vaporwear" would mean you're shrouded in smoke. This here is not smoke but plasma, and it's not doing the shrouding, it is itself shrouded in a magnetic field ("fluxwear", if you will), which following this discovery can be made more hardwearing than before, which will in turn protect from damage the hardware, which encloses the whole system and as such might be referred to as "hardwear" for the contents. It is important to be wary of the difference lest the reader grow weary. It's not really all that hard.
sudo ergo sum
Technically you can fuse iron - ask an astrophysicist for the gory details.
But it takes more energy to fuse than is released. So iron fusion is pretty much the last fusion reaction to be expected from an end-of-life reactor (of the thermostellar variety)
You either believe in rational thought or you don't
I'm not a scientist but is testing Nuclear Fusion in a very populated area a good idea?
I'm not a scientist either, but I have read a little on the subject....And from what I understand, the reaction would peter out and die very quickly - very little fuel is used in comparison to a fisson reactor, and the reaction itself requires very precise control to happen at all.
Comments like yours are part of the reason there's so much nonsensical backlash against this sort of technology - "I have no idea what i'm talking about, but it must be bad just because! Nuclear bombs are evil, so this must be the same!".
Couldn't they have done this in some place a little less populated? Like North Dakota or in the area near Area 51?
I would have one of these reactors in my backyard (well, if I wasn't in an apartment right now, anyway) with no reservation whatsoever.
The euro started trading at an artifically specified U$1.18, dropped quickly to just over $0.82 in actual markets, and has climbed from that natural valuation to $1.27. That's an over 54% increase. The euro's superiority is clear, defining supremacy over the formerly supreme dollar.
You can't be "sarcastic" simultaneously about both a false euro introduction rate of $2.00, and predicting the imminent supremacy of the euro. Especially when getting the intro rate wrong isn't sarcasm.
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make install -not war
Fission also produces neutrons.
Fusion produces orders of magnitude more neutrons.
In a fission plant, excess neutrons are bad. You want the pile to be barely critical, a stable, but not runaway, chain reaction. So you actually don't have a lot of neutrons flying out of the pile. You moderate the ones you do produce, and use them to fission additional fuel atoms.
But in a D-T fusion scheme, the bulk of the liberated energy is produced in the form of a very energetic 14 megaelectron-volt neutron. And this neutron doesn't participate in additional reactions, DT fusion isn't a chain-reaction process like fission is. The neutron will leave the plasma. Heck, ideally, that's how you get energy out of the reactor, by trapping that neutron in a surrounding blanket, causing that blanket to heat up so you can use that heat to boil water. Every single D-T fusion generates one of these neutrons, so the neutron flux will be many many times that of a fission plant.
But that's not an issue because of "radioactive waste." The wastes we're concerned about from fission aren't neutrons, they're from fission fragments and decay daughters. Some of those might emit neutrons themselves, but really, that's not the primary concern; neutron-induced radioactivity is actually pretty short-lived.
The reasons neutrons are a concern in a fusion plant is that continuous high-energy neutron bombardment does very bad things to all known materials that you might want to build a reactor vessel out of. When a neutron strikes an atom, it displaces it within the crystal lattice. If that happens once, no big deal, but in a commercial fusion reactor, the reactor vessel will experience 300 to 500 displacements per atom over the lifetime of the device. That means that, right now, we don't even know what to build one of these things out of. Austinitic steels start to swell, crack, and degrade after only about 30dpa, and the very best candidate materials we know of can only handle about 150; those might be acceptable, if the cost of changing the inner wall out isn't too high, but we just don't know.
And ITER won't even begin to explore those issues. ITER's flux will only generate 3 displacements per atom.
Fusion is very very hard. My money says that we'll never use commercial fusion power.
This is too far down for anyone to really see...pity.
Disclaimer: I am a fusion scientist.
The result mentioned in the article has been around for about a year in the fusion community. It is very good work, and opens up further areas of study. However, it is specific to a single Tokamak, and so far has not yet been repeated. Furthermore, the result has not yet been fully understood. (This is linked to it not being repeated.)
This may be sensational news, but it shouldn't be, due to claiming to solve a problem, which so far they haven't fully done. Don't take anything away from the guys who did this. Like I said, excellent work. But until the result is confirmed and understood it should stay out of mainstream media.
There are many big problems for fusion, like plasma instabilites, neo-classical tearing modes, ELMs (as mentioned), ohmic heating in transformer coils. The list goes on, it's a complex subject. Thankfully with all countries signed up, and more than enough money for ITER's budget (even if America pulls out again), the politics can be minimised and the physics can continue.