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Fusion energy breakthrough by Livermore Lab

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Re: Fusion energy breakthrough by Livermore Lab

#641

Post by liketochill »

moloch-hai wrote: post #599
donquixote25 wrote: post #535

Earlier quoted context omitted.

Yea, the whole target bay is in vacuum which helps with the arcing.

Vacuum is supposed to increase arcing. People who want to prevent arcing flood the cavity with sulfur hexafluoride. Fun fact, it has 25,000 times the "greenhouse potential" of CO2. Dunno if that includes lifetime in the atmosphere, or just instantaneous opacity to IR. All the wind turbines are pumped full of it. There is an effort on to switch to something else of proprietary composition.

A breaker can use sf6 gas but usually that is at 60 kV and above. For 35 kV and below vacuum bottle breakers are much cheaper than sf6.

individual wind turbines are not generating at more than 13.8kV so I would be surprised if they had any sf6 in them.

Re: Fusion energy breakthrough by Livermore Lab

#642

Post by dmix »

leephillips wrote: post #559
teilo wrote: post #518

Earlier quoted context omitted.

Early reports are are not good. For every joule delivered to the chamber, it takes 100 joules of electrical power. Heat to electricity is 50% efficient at best. Reports are that with 2.1mj of input, they generated 2.5 mj of output. Taking inputs and electrical production into account, this means 0.6% is all they are getting out vs. what they put in. These over-unity reports are meaningless, because every damn one of…

NIF people like to call this the “target gain”, but someone there has been whispering “net gain” to the journalists, in their ongoing campaign of deliberately deceptive hype. But “target gain” isn’t even (pellet output)/(laser output). The denominator is laser energy deposited in the hohlraum; the rest of it doesn’t count. And this deposited laser energy is estimated based on a model of laser deposition—it’s not meas…

> The modeling codes are classified

What is the justification for keeping it classified?

Re: Fusion energy breakthrough by Livermore Lab

#643

Post by simne »

zaking17 wrote: post #244

Would anyone knowledgeable about the field update their priors about whether we’ll see commercial fusion in the next 30 years, after seeing these results? If not, is there a big milestone we’re waiting for? Or will fusion advancement be a slow grind with many small improvements over decades?

Big milestone is construction materials, could long enough withstand neutron stream, which is about two magnitudes more, than in fission reactors.

This is last unknown in this equation. All others are already known, from achievements of last few years.

Materials research is one of primary targets of ITER.

If good enough materials will not being found fast enough, will need to use clear reactions like boron-carbon fusion, in which need magnitude higher temperature, so practical device will be few times larger (because x-ray losses, proportional to surface square of plasma configuration).

Re: Fusion energy breakthrough by Livermore Lab

#644

Post by TaylorAlexander »

pontifier wrote: post #584

I see I'm a little late to the discussion, but this is very similar to the patented Fusion device I've been proposing for several years here. http://www.DDproFusion.com The main idea behind my reactor is to contain NIF like explosions in magnetic fields. I've been trying to get a test reactor built for a long time, and my plans have been hampered by a theft earlier this year. A huge difference between the current NIF…

I thought I would let you know that you misspell "inertial" on your website as "innertial". Normally I don't point out spelling mistakes, but I think it may be more noticeable when pitching a nuclear fusion reactor.

https://en.wikipedia.org/wiki/Inertial_confinement_fusion

Re: Fusion energy breakthrough by Livermore Lab

#645

Post by simne »

dghughes wrote: post #571

What I found impressive was the failure or rather why it couldn't keep going wasn't due to the fusion process it was due to overheated magnets. Generating 59 MJ (11MW) in five seconds was impressive too although I didn't see what the amount of energy that was input. I'm also curious how are they going to heat water for the steam generators? Water can't be heated to 150 million degrees C something has to moderate it d…

With D-He3 process, most energy generates as neutrons (about two magnitudes more than in fission reactors) and as break x-ray.

Each will be converted to heat in walls and in shielding blanket, which cooled by water.

Re: Fusion energy breakthrough by Livermore Lab

#646

Post by TaylorAlexander »

rawgabbit wrote: post #367
steve_avery wrote: post #255

I have personally taken a tour of the NIF at Livermore. The guide was an old hand, who constantly remarked about the efforts of NIF towards "stockpile stewardship," ie the maintenance of the US arsenal of nuclear weapons. It seemed like NIF was all about the stockpile stewardship first, and fusion research was a secondary consideration. The capability of the NIF to get positive energy from the energy that they impart…

What is your opinion of ITER? https://edition.cnn.com/interactive/2022/05/world/iter-nucle...

Personally my money is on SPARC as a demo plant and its planned successor ARC as a commercial power plant prototype. Unlike ITER these systems use high field strength superconducting magnets, which directly translates to a much smaller machine for the same energy gain. Because of the smaller machine size, it can be built much faster than ITER. The company building SPARC plans to achieve first fusion around the same time as ITER, and since their machines are smaller, they should be able to move faster. That said ITER will be fantastically useful for proving a lot of science, and I am happy we have so many viable fusion projects in the works.

https://cfs.energy/news-and-media/new-scientific-papers-pred...

Re: Fusion energy breakthrough by Livermore Lab

#647

Post by Schroedingersat »

dmix wrote: post #642
leephillips wrote: post #559

Earlier quoted context omitted.

NIF people like to call this the “target gain”, but someone there has been whispering “net gain” to the journalists, in their ongoing campaign of deliberately deceptive hype. But “target gain” isn’t even (pellet output)/(laser output). The denominator is laser energy deposited in the hohlraum; the rest of it doesn’t count. And this deposited laser energy is estimated based on a model of laser deposition—it’s not meas…

> The modeling codes are classified What is the justification for keeping it classified?

Because it's a weapons program that is entirely unrelated to power generation.

Re: Fusion energy breakthrough by Livermore Lab

#648

Post by subradios »

crote wrote: post #525
belorn wrote: post #510

Earlier quoted context omitted.

> You see a lot of handwaving such as that very close to 0 statement with nuclear but someone’s got to be on the hook. Yes, and that one is society. It what we do with any risk that is so great that if any company would have to carry it then the company would fold and society would still have to carry it. Hydro power is one prime example. If a dam would break the damage downstream would be too high for any power comp…

Unfortunately your examples have been litigated in practice already, and reality does not agree with you. See for example [0], which is a nice writeup on the liability for dam failure. As it turns out, there are very few cases in which the operator would not be liable. Similarly, Pacific Power has been sued for wildfires in Colorado, and PG&E even plead guilty to manslaughter in the Paradise fire - and had to file fo…

That is not what is being said. What is being said is that there are two factors to nuclear accidents: 1. The actual costs of containment, cleanup, repair. 2. The arbitrarily imposed costs to satisfy a terrified public.

For power generation, humans just need electricity. This requires large networks of high voltage lines crisscrossing the country. Those lines will start wildfires at some rate X. A utility cannot survive being liable for all damages by that wildfire.

So what you do - is everyone buys insurance and the government sets "best practice" regulations designed to reduce X to a number considered reasonable. Investigations that result in litigation are usually what happens when the company has clearly violated best practice.

The problem with all things nuclear is that our vision of acceptable number and severity of nuclear incidents is that it needs to be negative.

Re: Fusion energy breakthrough by Livermore Lab

#649

Post by Schroedingersat »

uplifter wrote: post #570
DennisP wrote: post #302

Earlier quoted context omitted.

Seems like energy extraction would be similar to other D-T designs: surround the reaction chamber with molten FLiBe or lead-lithium and run some coolant pipes through it.

> surround the reaction chamber with molten FLiBe or lead-lithium So manufacturing fusion reactors would use a lot of lithium, which is already in short supply. That would be an interesting complication with the demand of lithium for electric vehicle batteries. Maybe the Li supply situation will be eased by then.

The quantity of lithium required is miniscule, but would require a fair bit of enrichment to eliminate the Li-6. The limiting resource is the inner wall for which no known material other than double the annual world production beryllium is even close to sufficient

Re: Fusion energy breakthrough by Livermore Lab

#650

Post by Schroedingersat »

rawgabbit wrote: post #367
steve_avery wrote: post #255

I have personally taken a tour of the NIF at Livermore. The guide was an old hand, who constantly remarked about the efforts of NIF towards "stockpile stewardship," ie the maintenance of the US arsenal of nuclear weapons. It seemed like NIF was all about the stockpile stewardship first, and fusion research was a secondary consideration. The capability of the NIF to get positive energy from the energy that they impart…

What is your opinion of ITER? https://edition.cnn.com/interactive/2022/05/world/iter-nucle...

Tokamaks are science projects and confusing them with electricity generators benefits no-one.
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