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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

#51

Post by nebopolis »

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 thing you are missing is that in addition to fusion power research (which is valuable and NIF has made major contributions to) there is also fusion weapons research. Inertal confinement is (kinda) close to the conditions inside a fusion bomb, and NIF also has a mandate to research those conditions. For that kind of research, a single pulse of fusion ignition is exactly the kind of data they need. Since we have a nuclear weapon test ban, and computer simulations need some kind of ground truth to be calibrated against, achieving fusion ignition in a lab is valuable to NIF for that reason alone.

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

#52

Post by HPsquared »

ph4 wrote: post #46

So is the goal just to fuel our current patterns of consumption and development with fusion, or nuclear, or whatever?

Would more cheap (in all ways) energy be a bad thing? I don't think so, people pay money for that sort of thing.

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

#53

Post by birdman3131 »

jacquesm wrote: post #7
tantony wrote: post #2

Is this "plasma breakeven" or overall break-even?

From TFA: "The pace of improvement in energy output has been rapid, suggesting we may soon reach more energy milestones, such as exceeding the energy input from the lasers used to kick-start the process."

These people grew up on Wow and are familiar with Soon™.

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

#55

Post by [deleted] »

xxpor wrote: post #43
ruste wrote: post #41

Earlier quoted context omitted.

When thinking of this amount of energy in kWh it seems small, but if this is deposited by lasers in a small fraction of a second it seems like a huge amount of power delivery.

Yeah, the time scale and volume of where it's happening matters a lot. It's like in fission when you read about reactions giving net energy of X MeV. If you convert that to even Wh, let alone kWh, it's an incredibly small number. But when you start multiplying by the number of atoms in a fuel source, it starts adding up VERY quickly.

[deleted]

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

#56

Post by dcow »

mlindner wrote: post #30
lisper wrote: post #13

Earlier quoted context omitted.

Neither. From TFA: "While the latest experiment still required more energy in than it got out, it is the first suspected to reach the crucial stage of ‘ignition’, which allowed considerably more energy to be produced than ever before, and paves the way for ‘break even’, where the energy in is matched by the energy out." Here [1] is an excellent video by Sabine Hossenfelder about why you should not get too excited abo…

It's neither, agreed. However, Sabine misconstrues things in the opposite direction and lies through omission to the audience. For example including startup energy and not ammortizing it over runtime, or not assuming that the energy consumption of the experiments is part of the required energy consumption of the fusion reactor, or trying to construe that once you have a fusion power reaction that is burning it is sti…

Where are you getting this impression? Her video pretty clearly focuses on the confusion between the Qs. Where does she get the napkin math wrong? She uses a published figure for total energy required during the operation of ITER when it’s up and running not a one time startup cost figure. Id she misrepresented that number, what would be a more honest total power consumption figure? As far as construing the output, she uses existing loss ratio for heat to electrical energy conversion which really does not seem to work to construe the problem as “especially difficult”, it’s “normally difficult” is how I interpreted. Are there impending advancements in energy conversion that makes 50% too liberal?

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

#57

Post by groby_b »

ph4 wrote: post #46

So is the goal just to fuel our current patterns of consumption and development with fusion, or nuclear, or whatever?

Assuming anything else would happen is ignoring human nature.

The only way to get significant reduction of consumption is via catastrophe. There's a good chance that'll happen, but there's no feasible different way that I can see. Take away large levels of comfort from large amounts of people, and you will inevitably see bloodshed. (Yes, I know that unsustainable consumption will also lead to catastrophe. Welcome to the 21st century, where the path forward is narrow and uncertain, while the stakes are higher than ever)

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

#59

Post by f00zz »

ph4 wrote: post #46

So is the goal just to fuel our current patterns of consumption and development with fusion, or nuclear, or whatever?

A lot of stuff becomes feasible with free unlimited energy. For instance, carbon air capture (could even become a protein source) and green hydrogen (for applications like production of iron via direct reduction, so we can finally get rid of blast furnaces).
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