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Nuclear fusion milestone passed at US lab

bbc.co.uk

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Re: Nuclear fusion milestone passed at US lab

#201

Post by shabble »

drjesusphd wrote: post #176
_b8r0 wrote: post #165

Earlier quoted context omitted.

Are you sure you're not thinking of JET[1]? ITER's not scheduled to be operational until 2020 AFAICR. Incidentally when I went to see JET (it's up the road from me, not that far from Oxford) the scale of the thing was enormous. They mentioned that they'd had been able to sustain plasma for 600 seconds. I've got some pictures up[2] on flickr. [1] - http://www.i15.p.lodz.pl/strony/EIC/ne/future_2_1.html [2] - http://ww…

I'm jealous you got to see JET. One of my favorite stories is the disruption. This happens when things don't go just right, and all the plasma with its energy squirts onto one spot. This typically puts the equipment in jeopardy. People try to prevent it, but as they push the boundaries of what's been done, it's going to happen. Keep in mind that there's only about as much mass in the entire chamber as in a few cubic…

The LHC beam-dumps[1] at CERN are also at that holy-shit-physics scale. A more explanatory article[2] also covers the superconducting magnet quenches, in which up to 10GJ of stored energy suddenly decides it really ought to be following Ohm's law again.

Any good refs for this disruption situation?

[1] http://lhc-machine-outreach.web.cern.ch/lhc-machine-outreach...

[2] http://www.symmetrymagazine.org/article/december-2007/protec...

Re: Nuclear fusion milestone passed at US lab

#202

Post by dekhn »

tezza wrote: post #163
XorNot wrote: post #152

Earlier quoted context omitted.

The ITER project's lifetime cost is currently less then the California rail system or a British rail extension. When people start talking about cost, let's put those numbers in perspective. The AIG bailout alone would've bought 6-7 ITERs.

> AIG bailout alone would've bought 6-7 ITERs. I agree with your other points. But the AIG bailout not only saved filthy rich bankers, but saved the entire world economy. Private pensions would have been wiped out, who own 95% of the stockmarket. The pensions were chasing gains and were quite happy while the returns were fat. The government cannot afford its own pension promises anyway and would have been wiped out.…

actually, big projects often have to be maintained because otherwise, huge numbers of highly paid scientists are let go. It's easier to shut down short-term, small-employee projects (like annually funded grants).

Re: Nuclear fusion milestone passed at US lab

#203

Post by crystaln »

Robin_Message wrote: post #162
crystaln wrote: post #137

Earlier quoted context omitted.

"commissioned by Greenpeace International" who I'm sure would back the position that nuclear fission plants are safer than coal. Of course, nuclear power plants are safe short term. Their threat is catastrophe, which given time, is inevitable.

Because of Greenpeace's history (the death of an anti-nuclear testing activist and the destruction of one of their ships at the hands of French special forces in 1985 [1]), and their current anti-nuclear stance [2], I don't think they would back that position. They would back the position that wind turbines are safer than coal, so you're not wrong that they might be biased to imply coal is more dangerous than it is.…

I was being sarcastic to point out the irony of referencing a Greenpeace study to support nuclear power over coal.

Re: Nuclear fusion milestone passed at US lab

#204

Post by crystaln »

ars wrote: post #157
crystaln wrote: post #137

Earlier quoted context omitted.

"commissioned by Greenpeace International" who I'm sure would back the position that nuclear fission plants are safer than coal. Of course, nuclear power plants are safe short term. Their threat is catastrophe, which given time, is inevitable.

Even with a catastrophe every 50 to 100 years nuclear kills far far less people than coal.

This is not really calculable, nor is the number of people killed by coal calculable in any reasonable manner. However the impact of nuclear catastrophe is far far more insidious and lasting, particularly when caused by a global calamity that causes meltdown in many plants.

Re: Nuclear fusion milestone passed at US lab

#205

Post by crystaln »

regularfry wrote: post #145
crystaln wrote: post #137

Earlier quoted context omitted.

"commissioned by Greenpeace International" who I'm sure would back the position that nuclear fission plants are safer than coal. Of course, nuclear power plants are safe short term. Their threat is catastrophe, which given time, is inevitable.

Greenpeace are not pro-nuclear.

I was being sarcastic to point out the irony of referencing a Greenpeace study to support nuclear power over coal.

Re: Nuclear fusion milestone passed at US lab

#206

Post by drjesusphd »

dekhn wrote: post #200
drjesusphd wrote: post #194

Earlier quoted context omitted.

> we have only ever invested money in fusion (risk) and have never received any useful power for it (payoff) Now you're just being silly. You can say this about ANY research project. Better scrap the Manhattan Project before it finishes, we haven't seen any results. You're saying it's impossible to build a fusion power plant because we don't have one now? Nevermind the fact that magnetic fusion research has been gros…

By the time the Manhattan Project started, we had already made signficant progress. Such as Fermi's pile. We knew how to seperate uranium. The math was all there; it was mostly a matter of decision-making and execution. I never said anything was impossible. But fusion is still solidly an unknown unknown: we have no credible path at this time to even plan a workable test reactor. I'm saying, for the amount invested, t…

That's just not true, and skirts the line of the being a deliberate lie. Fusion has occured in tokamaks, at an efficiency of 65%. ITER, as currently designed and being built, is expected to make a 10-fold return on energy input.

We are precisely at the position of "the math is all there" with regard to magnetic confinement. And so is the engineering and the funding (barely). It's going to happen, hopefully not before it's too late.

Re: Nuclear fusion milestone passed at US lab

#207

Post by ars »

crystaln wrote: post #204
ars wrote: post #157

Earlier quoted context omitted.

Even with a catastrophe every 50 to 100 years nuclear kills far far less people than coal.

This is not really calculable, nor is the number of people killed by coal calculable in any reasonable manner. However the impact of nuclear catastrophe is far far more insidious and lasting, particularly when caused by a global calamity that causes meltdown in many plants.

> This is not really calculable, nor is the number of people killed by coal calculable in any reasonable manner.

Of course it is. 161 people are killed for each THw of coal energy. And 0.04 people for each THw of nuclear power and this INCLUDES Chernobyl!

http://nextbigfuture.com/2011/03/deaths-per-twh-by-energy-so...

http://www-958.ibm.com/software/data/cognos/manyeyes/dataset...

> However the impact of nuclear catastrophe is far far more insidious and lasting

Clearly you've never seen https://en.wikipedia.org/wiki/Kingston_Fossil_Plant_coal_fly... the radiation and heavy metals released from that can never be cleaned (just diluted).

> particularly when caused by a global calamity that causes meltdown in many plants.

A what?? And how do you manage that? If you have unreasonable fears then there is no point in talking to you. Reason will not remove an unreasonable fear.

Re: Nuclear fusion milestone passed at US lab

#208

Post by chris_mahan »

dekhn wrote: post #199
chris_mahan wrote: post #193

Earlier quoted context omitted.

Also, see http://xkcd.com/980/ for the scale of money, where you realize a trillion is not a lot of money either.

A trillion is a lot of money. No single corporation controls that much capital; even the largest are just half-way there. Very few organizations can organize and control that amount of money. I agree that compared to the total circulation of virtual money, $1T is small compared to the total.

So, then, 100 billion dollars would not be considered a lot of money either.

Although, to put things in perspective, the FBI budget it 8 billion per year.

Re: Nuclear fusion milestone passed at US lab

#209

Post by nikatwork »

dekhn wrote: post #188
nikatwork wrote: post #122

Earlier quoted context omitted.

> That appears to be an accident handling the output of an isotope manufacturing reactor, not anything involving a power reactor. That is irrelevant to my point, which is that the biggest risk to reactor safety with current fission tech is human error and negligence. > compare almost any form of mining The only form of mining comparable in terms of potential environmental damage is ocean oil drilling[1], which I also…

If your technology has reached the point where human error and negligence is the primary source of risk, you've succeeded. That is the goal of producing all reliable technologies. Of course, at that point, your system design primarily exists to prevent human errors from causing harm (for example, yesterday there was a news report that a Fukushima cleanup worker managed to engage a pump that would dump a bunch of radi…

> If your technology has reached the point where human error and negligence is the primary source of risk, you've succeeded.

If all it takes is one earthquake or distracted technician to potentially vaporize a suburb, then your tech has not yet succeeded.

Safety regimes to minimize human error are great, but time and time again they are bypassed due to greed, negligence and idiocy. The Fukushima backup system you mention is exactly the kind of thing I'm talking about - but they need to be comprehensive, redundant, and responsibly audited (the part that scares me the most).

Re: Nuclear fusion milestone passed at US lab

#210

Post by eru »

waps wrote: post #181
eru wrote: post #143

Earlier quoted context omitted.

You are forgetting about opportunity costs. People could have done those things without a war or weapons research.

They would never have gotten funding for it. No way in hell. Plus, war made sure that they put getting working reactors first. Not interesting science. A critique in fusion research is that nice, flexible and very accurate/complex apparatus is given preference over quick-iteration and fast experimentation. War made sure that the researchers went straight for the goal (and there is the fact that the Germans and the Am…

Yes. But in peace time we do not lose more than half the countries manhours blowing other countries up.
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