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Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

imperial.ac.uk

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Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#121

Post by Scarblac »

rfrey wrote: post #61

Meta-question about fusion energy -something I don't understand about the movement. I spent a few years as CTO of a company providing heat-to-electricity plants. We financed and built them off high-heat plants like natural gas turbines. The "fuel" was heat going up the stack - so it was essentially free. We still couldn't compete with conventional electricity plants, even with a $30/tonne price on carbon in Canada. G…

Natural gas costs don't include the external costs like climate change, so it looks better than it is. We have to stop using fossil fuel soon to prevent really catastrophic changes, so then other sources are needed.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#123

Post by Krasnol »

vfclists wrote: post #19

Funny how this story gets posted after soon after Dr Sabine Hossenfelder's debunking and deflate the fusion power hype - https://www.youtube.com/watch?v=LJ4W1g-6JiY with a genuine Hans Gruber accent :)

It's even funnier how fast you got downvoted.

The nuclear band wagon is strong here.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#124

Post by 420official »

BizarroLand wrote: post #109
orangepurple wrote: post #66

Earlier quoted context omitted.

You can't put a price on energy independence in a free market economy. Energy independence is a military objective and a matter of national security. The costs are difficult to put in perspective.

Oil companies are subsidized to the tune of Billions of dollars an hour. Subsidizing fusion energy would merely be redirecting that money to the greater payoff.

This is not true.. 1 billion an hour is 8.76 trillion a year yet you say "billions" an hour which would make it at least 17.52 trillion a year which is basically the entire GDP of the us.

Certainly oil companies are subsidized but not "to the tune of" the entire US GDP.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#125

Post by hinkley »

woah wrote: post #75
hinkley wrote: post #62

Earlier quoted context omitted.

Heat pollution. Green house gasses are not the only way to cook ourselves. Though there are some people working on beaming heat into space, I suspect they haven’t fully accounted for heat absorption by atmospheric dust.

I'm guessing any possible energy generated by manmade fusion plants would be miniscule compared to that hitting the earth from the sun every day.

That's not how homeostasis works.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#126

Post by jjk166 »

hangonhn wrote: post #39
gene-h wrote: post #20

Earlier quoted context omitted.

What's important here is that they may have achieved ignition, that is making the fusion reaction self sustaining[0]. Once it becomes self sustaining one should be able to add more fuel to the pellet to get more energy out for the same input energy. It's worth noting that NIF was not intended to generate power and is not representative of a potential power plant. The lasers on NIF are old and were chosen to have a lo…

What is the goal of NIF? I've read repeatedly that fusion power isn't their end goal but rather to study inertial confinement. That's fine but why study inertial confinement if not to generate power? I've always been very confused about their goal. I'm a total layman when it comes to this stuff so there's some nuance I'm not understanding. Appreciate any clarification anyone can give.

The NIF is a facility for conducting experiments. The goal for the field is fusion power, and these experiments may wind up contributing toward it, but it will never be anything more than a stepping stone. The primary purpose of the NIF is validating computer models for simulating nuclear reactions. These models are used both for the design of nuclear weapons and nuclear reactors. They also develop technologies to support their activities, such as new sensors and laser control methods. Compare this program to say a mars rover where we don't expect the rover itself to do anything of great practical utility, but the lessons learned along the way have many potential applications both directly for future missions, and indirectly for spinoff technologies.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#127

Post by kragen »

tsimionescu wrote: post #120
kragen wrote: post #54

Does this mean you can now build a hydrogen bomb without uranium or plutonium? If not, why not?

Because to achieve 1MW of energy from fusion, you put 200MW of power into the lasers. And, you have to fire these lasers with unfathomable precision at a tiny piece of gold, in order to heat up an even tinier pellet of hydrogen, which then heats up enormously for a few milliseconds before fizzing out. ICF is a good way of studying what happens inside a hydrogen bomb, but it is in no way imaginable how you could use i…

What stops you from using the "even tinier piece pellet of hydrogen"[sic] from initiating fusion in a slightly less tiny pellet of hydrogen that it's sitting on top of, which initiates fusion in a slightly less tiny pellet of hydrogen, and so on? Aside from concern for your own survival, of course.

Maybe if you can't fathom the precision required to irradiate the NIF hohlraum sufficiently isotropically to achieve ignition in the first place, you shouldn't be trying to answer this question.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#128

Post by pstrateman »

BizarroLand wrote: post #109
orangepurple wrote: post #66

Earlier quoted context omitted.

You can't put a price on energy independence in a free market economy. Energy independence is a military objective and a matter of national security. The costs are difficult to put in perspective.

Oil companies are subsidized to the tune of Billions of dollars an hour. Subsidizing fusion energy would merely be redirecting that money to the greater payoff.

The hyperbole isn't needed.

Billions of dollars an hour is 17 Trillion dollars a year.

They're not being subsidized by that much

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#129

Post by floatingatoll »

wolf550e wrote: post #78

@dang This was reported and discussed 12 days ago: https://news.ycombinator.com/item?id=28704298 The important thing to know is that the NIF is about nuclear weapons design (verification of modeling software used for nuclear weapons design), not about developing fusion power plants.

Note that @dang doesn't actually notify dang, unless he happens to open this article and see it out of the corner of his eye or something. If you want to report a frontpage dupe, emailing the mods using the footer Contact link is an efficient method (or you can just flag it as I did, which has relatively the same effect if enough people do).

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#130

Post by tsimionescu »

kragen wrote: post #119
coolspot wrote: post #96

Earlier quoted context omitted.

Man-made nuclear fusion is not self-sustaining, requires massive infrastructure to ignite very little of material. Nuclear fission of unstable isotopes is self-sustaining chain reaction that converts a lot of matter into energy without much of hardware - just put some sub-critical mass of Plutonium into a sphere lined with conventional explosives. See also: https://en.wikipedia.org/wiki/Pure_fusion_weapon

Well, of course that's always been true in the past, but isn't "ignition" precisely the point at which it becomes self-sustaining? Isn't that the distinction between "ignition" and not "ignition"? I mean, you're not the right person to ask (you apparently think plutonium is a brand name), but maybe somebody reading this understands the issues. You don't even need explosives to get a self-sustaining nuclear fission ch…

Ignition in the case of ICF means that, for the brief time while the shockwave from the initial laser burst is still keeping the plasma together, you get to fuse all of the D+T in your pellet. Once the initial velocity is lost, the high-temperature He dissipates away.

Not ahcieving ignition means that the plasma cools too rapidly and the fusion reaction stops even before the brief microseconds of inertial confinement are lost.

Perhaps if you could deliver enough energy to a large enough pellet, you could use this to build a bomb, but today it is far too small for that, and the reaction wouldn't work with a larger fuel pellet (the geometry that allows the extreme pressures needed for fusion would not be easily achieved with a larger pellet, since even the wave-length of the laser is relevant at this level).

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