New 'Stellarator' Design for Fusion Reactors 171
eldavojohn writes "The holy grail of fusion reactors has always seemed 'just a few years off' for many decades. But a recent design enhancement termed a 'Stellarator' may change all that. The point at which a fusion reactor crashes is when particles begin escaping due to disruptions in the plasma. A NYU team has discovered that coiling specific wires to form a magnetic field may contain the plasma. This may be a a viable way to create a plasma body with axial symmetry, and a far better chance of remaining stable. Like other forms of containment this does require energy itself, but could bring us closer to a stable fusion reactor. It may not be cold fusion or 'table top' fusion but it certainly is a step forward. The paper is up for peer review in the Proceedings of the National Academy of Sciences."
Thorium reactors (Score:5, Interesting)
Does anyone know any more about this?
Why reinvent the wheel? (Score:5, Interesting)
1. Contain a plasma ball with high density for fusion reaction. Ball is much better than doughnut if you just can figure out a way to keep the plasma together.
2. Make a wall that is far enough away to not melt from this plasma ball to absorb heat/radiation to make power, and keep it close enough to get high enough energy density on its face.
3. Make the wall 1 ton/m^2 to protect the people outside
4. Use magnetic field outside plasma ball to contain radiation.
This seems like a tall order, and it is, but consider the sun/earth:
1. Gravity works great compared to magnetism.
2. Well, here on the earth, it is 1kW/m^2. That is much higher than the energy consumption in most cities. Should be good.
3. Our atmosphere stupid.
4. The earth again has a great magnetic field that protects us pretty well.
Bottom line: Why reinvent the wheel?
Re:input-output (Score:2, Interesting)
It could also be that it's a brute force attempt to force cohesion, and since force must be met with equal force it's very difficult. That also assumes it could concentrate the exact amount of energy at exactly the right point. Just imagine trying to not only stop a terrorist attack, but subdue them without lethal force. They need one leak to win. You need a perfect record.
Nice News for Nerds but... (Score:2, Interesting)
Unless I'm wrong, the production of non-military nuclear reactor designs in the US for the last 30 years have been... zero. Unless you count the Galileo, Ulysses, and Cassini space probes. Call me when we upgrade all of our reactors from 1973 designs [wikipedia.org] to a much safer and cleaner Gen IV [wikipedia.org] design -- like this bad boy [ga.com] (now with free hydrogen!) instead of taking high-level radioactives --potential fuel-- driving them recklessly around the country in truck, and shoving it into a salt mine, or some similar brilliant idea.
Besides, though I lust for the sheer coolness of magnetically confined plasma as much as any proper geek, the the simple fact is we have had the technology to use fusion for power [wikipedia.org] for quite some time now [sandia.gov](press release from 1998, although building the X-1 was promptly cancelled without reason) with Z-pinch inertial confinement on the insanely cool Z machine [sandia.gov] at Sandia.
Yawn. Wake me went the politics of our time aren't ruled by Luddites with pitchforks and torches...
Re:Thorium reactors (Score:4, Interesting)
It's important to define 'better' here. Cost would seem to be an important consideration, for example. I don't know what the price tag of fusion is so far, but it's awfully, awfully high already and without a great deal to show for it. If we've already got a pretty good thing in thorium, and we already have the reactors, and there's enough thorium and uranium to keep us in electricity at present consumption rates for thousands of years, and it's non-polluting and all the rest, then how is fusion - a hugely expensive, so far unproductive technology - 'even better'. I'm not quibbling or trying to be antagonistic here - it's a serious question, and it needs a serious answer considering what's at stake: we need clean, non-polluting power that doesn't ultimately come from politically volatile parts of the world.
Re:If they used... (Score:3, Interesting)
Still concave toward the plasma. (Score:3, Interesting)
(My take on that has been that even if passive geometries are unstable, if you can get it stable enough that instability growth occurs at no more than an HF rate you might be able to use an active system to finish the job of stabilizing the confinement. But that's a separate issue.)
Re:Thorium reactors (Score:3, Interesting)
I don't know if that will ever happen. With most sources of energy, the fuel is unevenly spread around the globe. And being some small country that has a huge reserve of some kind of fuel will tend to mess your country up in the same way that people who inherit a lot of money (and never have to work a day in their lives) get messed up.
Trade doesn't always have to create political instability, but it certainly doesn't help when you have a country that controls some resource that society must have in order to keep functioning. If someone must have something, they're willing to take it. And conversely if you have something that someone else needs, you tend to behave however you damn well please.