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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

#391

Post by pfdietz »

ivix wrote: post #297
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…

The cost of a fusion plant will be a small fraction of the cost of a fission plant, where the extreme safety requirements makes it expensive. People are now testing fusion in small regular industrial facilities.

Engineering studies over the years have come to the opposite conclusion. Fusion reactors will be much larger than and much more complex than fission reactors, and hence much more expensive.

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

#392

Post by pfdietz »

cbtacy wrote: post #383
mraison wrote: post #241

Earlier quoted context omitted.

It's hard to compare a fusion plant and a geothermal plant if we don't know how much energy a single fusion plant could produce. Are there any estimates on that?

https://www.lockheedmartin.com/en-us/products/compact-fusion... "A reactor small enough to fit on a truck could provide enough power for a small city of up to 100,000 people."

After 2014 they expanded the volume of that putative reactor by a factor of 100. Also, fitting on a truck was always assuming no neutron absorbing blankets (which have to be ~1 meter thick.)

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

#393

Post by freeopinion »

Mewit wrote: post #326
humaniania wrote: post #213

Earlier quoted context omitted.

"impermeable" until there's an earthquake caused by fracking and things shift deep underground where nobody can monitor or track what is happening? Seems exceptionally short sighted to me. https://www.usgs.gov/faqs/does-fracking-cause-earthquakes

I think it's best to look at the options through a risk matrix. Is it possible that an earthquake is generated by fracking that is big enough to geologically connect a hydrocarbon formation with a surface aquifer thousands of feet above it? I suppose, but I think it is very unlikely. I don't think there are any cases of that on record, and wells have been fracked in the US for many decades (although not as frequently…

You left out the matrix on the other side of the equation.

What is the cost of not fracking? Very, very debatable.

On a case by case evaluation, the risk from any single fracking well seems much higher than the risk of not using that well. On the aggregate, the calculation may be different. But again, it is all very arguable.

In an argument of this consequence, the side that says, "That's secret information" should lose.

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

#394

Post by harles »

ClumsyPilot wrote: post #371
Robotbeat wrote: post #218

Earlier quoted context omitted.

Internal combustion piston engines also do intermittent combustion. If you were to make a power plant based off of this, you would need dozens of these per second (and much more efficient lasers and a tritium breeding liquid lithium metal jacket and… a lot of other stuff).

The capsules are tiny and do not generate usefull amount of energy. ITER is planned to generate 500,000,000W. Thats actually usefull

500MW of heat from 620MW of electricity seems far from useful. Interesting, but not useful.

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

#395

Post by jboy55 »

Animats wrote: post #133

Oh, this is just laser fusion. One pulse of power. That's not a power source, even potentially. It's a lab-sized H-bomb experiment. This isn't one of the magnetic containment systems achieving ignition and sustaining the reaction. Now that would be an achievement.

The laser produced 1.3 MJ from fusion in an instant using only around 250 KJ of laser energy. We have already created machines that fuse hydrogen and from only 3 KJ of electricity, produce 10^10 MJs of energy out of it in an instant.

I never got the appeal of the laser experiments, they must be covers for weapon research.

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

#396

Post by ClumsyPilot »

xondono wrote: post #236
humaniania wrote: post #221

Earlier quoted context omitted.

Energy subsidies for vulnerable people are an option that negates your only argument against the most sane option of switching to renewable and nuclear ASAP, at least in extremely wealthy countries like the USA.

My argument doesn’t care who’s pocket is funding the renewables. As a society, every extra dollar spent on pricier energy is an extra dollar that can’t go to social programs, or to new start up, or anywhere.

"As a society, every extra dollar spent on pricier energy is an extra dollar that can’t go to social programs, or to new start up, or anywhere."

I am not buying it, energy is cheap, so we waste it by shipping a pair of jeans three times across the world, to deliver fast fashion the consumer needs, so that on average they can wear some low quality bullshit made woth slave labour 7 times and then throw it away, to be shipped into some poor country for 'recycling' and have it end up in the ocean.

Or catch shrimp near our shores, ship it to philipines to be peeled, and then shipping it back.

Passivehaus standard was developed decades ago, it is several times better than the maximim energy efficiency rating in UK of 'A+'. The number of houses that meet either of these standard is a fucking 0%. Check newbuilds in Uk, half of then can't manage energy rating of C, its, disgracefull! Almost none of them have a heat recovery ventilation system or a heat pump. We waste 20-30% of energy we generate on heating leaky homes.

My parents used to buy groceries at the market by weight, today a 300 g steak comes with 200g plastic packaging. 70% of my trash is plapackaging. The recycling rate is 9%. Efficient free market my ass.

The only place I know that sells food without plastic us an hour travel away, it's a hipster place with organic-artisian authentic beans at 1,000% markup. There is nobody who sells milk in a container I could return to them when it's empty, mo matter how much I pay.

What bancrupts an average consumer? Unaffordable housing, education and healthcare. None of these things are dictated by energy price.

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

#397

Post by pvg »

jboy55 wrote: post #395
Animats wrote: post #133

Oh, this is just laser fusion. One pulse of power. That's not a power source, even potentially. It's a lab-sized H-bomb experiment. This isn't one of the magnetic containment systems achieving ignition and sustaining the reaction. Now that would be an achievement.

The laser produced 1.3 MJ from fusion in an instant using only around 250 KJ of laser energy. We have already created machines that fuse hydrogen and from only 3 KJ of electricity, produce 10^10 MJs of energy out of it in an instant. I never got the appeal of the laser experiments, they must be covers for weapon research.

It's not a cover, it's an explicit purpose of the facility:

NIF uses lasers to heat and compress a small amount of hydrogen fuel with the goal of inducing nuclear fusion reactions. NIF's mission is to achieve fusion ignition with high energy gain, and to support nuclear weapon maintenance and design by studying the behavior of matter under the conditions found within nuclear weapons

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

#398

Post by [deleted] »

Animats wrote: post #133

Oh, this is just laser fusion. One pulse of power. That's not a power source, even potentially. It's a lab-sized H-bomb experiment. This isn't one of the magnetic containment systems achieving ignition and sustaining the reaction. Now that would be an achievement.

[deleted]

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

#399

Post by omgJustTest »

PhD nuclear engineer here:

The National Ignition Facility (NIF) is a fusion facility that seeks to study fusion (ie, meet the Lawson[1] criteria) through compression of a tiny spec of tritium or deuterium-tritium ice inside of a cylindrical tube called a Hohlraum[2]. Achieving fusion in this case can be assessed by a simple energy balance, canonically referred to as the "Q" factor[3]. Q=1 implies the fusion process released the same amount of energy the input-laser put in to the reactor. Q=2 is largely accepted as the minimum viable criteria for a fusion-power reactor (one unit of Q to return to the reactor, one unit of Q to be exported to the grid, power conversion unit etc for actual use).

1.3MJ is the claimed number by the article, while impressive for inertial confinement fusion (ICF), it lacks the context that the laser-input-power is ~2-4MJ (ie a Q~0.5).

A bit more context: the best-of-the-best shots at NIF produce an idealistic energy balance that cannot sustain a reaction. There are a lot of other practical considerations such as how you would provide continuous power from the NIF Holhraums, what materials would stand up-to 100 DPA [4] damage from radiation bombardments, and a host of others.

An open secret is that NIF's purpose is not exclusively fusion.

Additionally JET appears to have a Q~0.67 according to wikipedia [3].

[1] https://en.wikipedia.org/wiki/Lawson_criterion [2] https://en.wikipedia.org/wiki/Hohlraum [3] https://en.wikipedia.org/wiki/Fusion_energy_gain_factor [4] https://gcep.stanford.edu/pdfs/UVaodfDrAb3BdgeRCpoy-w/10-Zin... slide 11.

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

#400

Post by neltnerb »

truculent wrote: post #359
jhgb wrote: post #237

Earlier quoted context omitted.

When I was younger (like three decades ago), the number I was taught was something like two million years (if I remember it correctly; I might still be able to find that book if I'm lucky).

To add to the confusion, I vaguely recall a number of around 125,000 years. I think it was either from "A Brief History of Time" or Jeff Forshaw's "Why Does E=mc2?".

carbon dating is really unreliable on photons.
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