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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

#171

Post by VLM »

dekhn wrote: post #48

A good place to start if you want to understand the purported rationale for the NIF (stockpile stewardship), I suggest reading and understanding this light introduction to modern nuclear weapons. http://en.wikipedia.org/wiki/Thermonuclear_weapon (the rhodes books, Making of the Atomic Bomb is required background reading, as is Dark Sun, if you want to get into the backstore). In particular: The NIH experiment recapit…

"stop investing in ... smaller plants."

Thought experiment... begin the experiment with the assumption that the "system" can produce and sustain 2000 brains capable of safely operating a nuke plant. You can build 1000 slightly less safe but bigger plants, or 10000 smaller slightly safer small plants, but you've still only got 2000 usable nuke level brains to staff them. Either half the big brains are going to be unemployed, or 80% of the only very slightly safer plants are going to be run by morons. Don't amuse me with deus ex machina about automation; I'll counter by changing my thought experiment to only 2000 nuke-capable sysadmins are available or whatever.

Re: Nuclear fusion milestone passed at US lab

#172

Post by tezza »

XorNot wrote: post #167
tezza wrote: post #163

Earlier quoted context omitted.

> 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.…

The point is that governments have this type of money. In spades. Pretending we're not properly prioritizing one type of research or another is a farce - if you can convince anyone to invest in nuclear fission reactors, whether they do that won't really be affected by how much fusion research is happening. That's not why we don't have nuclear fission right now, but shutting down nuclear fusion might just ensure we ne…

The government guaranteed AIG's losses. They opened themselves up to earth shaking liabilities.

But very little was actually required in the end ( their hope / educated guess at the time it was entered into ).

If the losses had been spectacular, the situation would have been desparate and the US would've had to take further evasive action.

This is a far cry from stumping up that amount of actual cash required for research.

Re: Nuclear fusion milestone passed at US lab

#173

Post by jameshart »

XorNot wrote: post #155
anirul wrote: post #147

Earlier quoted context omitted.

I can answer to one of your question, there is forty more world class fusion scientists (especially young one with new ideas). They usually are kicked out of research because of no money and send into the job market into financial and other jobs. So this could help everyone if these more qualified people could stay in research and not take a spot in a job that can be filled by a less skilled person.

Also, high-level research projects push the state-of-the-art in the private sector. When CERN order up a new type of magnet, that contract goes to a company who does magnet winding who in turn usually revamp their entire process as part of the collaboration to achieve the desired field strength, homogeneity and size. Suddenly, there's now a company which can do that - and is eager to sell the service on since they no…

I'm not arguing against investment in big science and R&D, I'm arguing against it as a form of stimulus spending.

Re: Nuclear fusion milestone passed at US lab

#174

Post by sam »

mrterry wrote: post #95
acadien wrote: post #70

Earlier quoted context omitted.

Finally someone that's actually in the fusion field. Could you say whether or not the NIF research represents a practical path towards a fusion based power source? My understanding is that it would at least be capable of capturing some much needed high pressure empirical data necessary for validating theory. On a side note concerning the NIF funding, the US gov will spend huge sums of money studying Nuclear weapons (…

I've worked in ICF for a nearly a decade. I think NIF research is a necessary step to a ICF based power source. If NIF demonstrates ignition, it can be used to validate our physics models of ICF (turbulence, fusion product transport, thermal conduction, etc). These physics questions are shared by all ICF approaches. However, a fusion power plant will use entirely different laser technology [1], and most likely a diff…

Good to see a commenter with an ICF background (most of what I know of ICF was only from water cooler chit-chat).

I didn't manage to get a thesis out. I left the PhD program before the funding was cut, but the writing was on the wall.

Yes, it is short sighted to cut funding of small scale plasma confinement concepts. They are high risk / high reward projects which are not expensive ~$1M. And even if they don't pan out as viable confinement schemes, they make for great training platforms for graduate students.

Re: Nuclear fusion milestone passed at US lab

#176

Post by drjesusphd »

_b8r0 wrote: post #165
ballard wrote: post #138

Earlier quoted context omitted.

IIRC from a recent HN discussion, ITER has attained Q of 0.65 and NIF is nowhere close to that.

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 centimeters of air; it's basically a vacuum. But what little there is is so hot, and there's so much energy wound up in the fields. When JET had a disruption, the entire machine, the largest tokamak in the world, LIFTED ITSELF OFF THE GROUND AND JUMPED A FEW FEET OVER.

Re: Nuclear fusion milestone passed at US lab

#177

Post by bandy »

tanzam75 wrote: post #112
cyanoacry wrote: post #92

Earlier quoted context omitted.

This is definitely true, and the BBC totally omitted these facts. The official NIF announcement[1] tried a little bit to cover their tracks. They posted some flashy numbers about the total energy output from neutrons, but nestled in the bottom of the page is the total energy dumped into the entire system: 1.7 megajoules. In comparison, the fusion power produced was a paltry 8 kilojoules, which they compare to the "en…

> total energy dumped into the entire system: 1.7 megajoules. In comparison, the fusion power produced was a paltry 8 kilojoules In other words, the National Ignition Facility hasn't achieved ignition yet. If you can actually achieve ignition, then nobody will care about the megajoules needed to get it ignited. Because once you've got ignition, you can get an arbitrary amount of energy out. But if you can't get ignit…

While they have had problems in the recent past: https://www.sciencenews.org/article/ignition-failed

~~ They've since had ignition: http://www.independentnews.com/news/article_792110c0-2c5b-11... ~~

[I'm positive that the ICF's predecessors also achieved ~~ignition~~ fusion on smaller scales.]

The real trick is that [0] you need to get out more than you put in (exceed break-even) [1] you need to be able to harness the energy produced by the ignition and [2] be able to do it over and over again, producing reliable power.

Re: Nuclear fusion milestone passed at US lab

#178

Post by dekhn »

XorNot wrote: post #152
drjesusphd wrote: post #133

Earlier quoted context omitted.

> What I am saying, is that relative to other potential investments, fusion does not seem to be a worthwhile investment, as the risk/payoff ratio is worse. I disagree. There exists MILLIONS of years worth of fuel on earth, compared to a few decades of oil and gas, and a few hundred years worth old coal or fissionable uranium. That's quite a huge payoff for relatively little risk (compare fusion research funding with…

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.

yes. I think the california rail system is also an overpriced underperforming system. It will never be finished (it will never make it all the way to SF), so it will never be completely useful, and the history of all large projects like this show huge cost overruns. Do you really want to allocate capital like that for something that's unlikely to be finished, nor likely to achieve its actual goal? When we could spend money to make cars more efficient (electric batteries with central generation) and reduce our total energy consumption, fairly cheaply?

Re: Nuclear fusion milestone passed at US lab

#179

Post by dekhn »

XorNot wrote: post #167
tezza wrote: post #163

Earlier quoted context omitted.

> 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.…

The point is that governments have this type of money. In spades. Pretending we're not properly prioritizing one type of research or another is a farce - if you can convince anyone to invest in nuclear fission reactors, whether they do that won't really be affected by how much fusion research is happening. That's not why we don't have nuclear fission right now, but shutting down nuclear fusion might just ensure we ne…

You think governments have this type of money in spades?

The US does not. We're in a major debt crises and have issues funding our fundamental operations; beyond the immediate government funding, we have severe problems with spending (IE, we can't pay the interest on our spending with our tax revenues).

Re: Nuclear fusion milestone passed at US lab

#180

Post by pdonis »

rdl wrote: post #161
andygates wrote: post #153

Earlier quoted context omitted.

But the backup generators could be moved (and were in similar US installations). Raising the backup generators to protect them against inundation was recommended, but the delay there is pure sclerotic TEPCO.

I still don't understand why Chinooks weren't in the air toward Fukushima within 30 minutes of the tsunami with some generators sling-loaded under them (and refueling, etc.). Either from the JSDF or US Military.

As I understand it, the issue was that not just the generators but the switchgear connecting them to the plant's power grid was behind the seawall that was overcome by the tsunami. So bringing in other generators wouldn't have helped, because there was no way to plug them into the grid.
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