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Major breakthrough on nuclear fusion energy

bbc.co.uk

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Re: Major breakthrough on nuclear fusion energy

#251

Post by treis »

m_fayer wrote: post #104
twobitshifter wrote: post #91

Earlier quoted context omitted.

Even if it takes 200 years it is likely still worthwhile. Unfortunately we, as a culture, have a problem seeing and planning across generations. https://longnow.org/

I'm happy to hear someone make this point. Rather than sneering "vaporware" when decades fail to crack a problem, I would prefer us to keep in mind that if we never try multi-generational projects, we will never taste the fruit of multi-generational projects, and those are some sweet fruit indeed.

It runs into the spaceship problem where later iterations of a spaceship reach the destination first because new technology allows them to fly faster. At some point (maybe) materials and other technology will develop enough so that fusion becomes feasible on a decades or so timeline. Or solar & battery technology will develop to the point where fusion isn't really needed.

Re: Major breakthrough on nuclear fusion energy

#254

Post by andrepd »

Wiseacre wrote: post #226
khafra wrote: post #182

Earlier quoted context omitted.

"Fusion is always 30 years away" is a heuristic that almost always works. https://astralcodexten.substack.com/p/heuristics-that-almost...

We haven't even been splitting atoms for a full century yet. Give science some goddamn time to work.

Not to mention we haven't invested a fiftieth of what we should have into fusion research.

Re: Major breakthrough on nuclear fusion energy

#255

Post by robbomacrae »

lisper wrote: post #199
robbomacrae wrote: post #187

Earlier quoted context omitted.

Your description made me wonder if it would be possible to make an ICE to extract the power. I then found a paper called Fusion Internal Combustion Engine from 2010 [0]. Does anyone know if there was any merit to this idea and if anything else has come of it since? 0: https://www.researchgate.net/publication/215544178_Fusion_In...

A few elementary calculations reveal how feasible this might be. A typical ICE produces a few hundred horsepower using 4-8 cylinders rotating at a few thousand RPM. 1 HP = 745 watts. Figure out how much energy is released per cylinder on each cycle, and compare that to the energy released in a typical fusion ignition. Also note the cycle time of an ICE rotating at a few thousand RPMs, and compare that to the cycle ti…

I'm a layman and so its possible I am missing some limiting factors but I do feel as though this rebuttal does not take into account the possible ranges of values that can be configured when tweaking things like scale and operating speed. For example the Wärtsilä-Sulzer RTA96-C operates at 15-102 RPM generating 100,000 HP (or 74.5 megawatts for your comparison) [0].

Nor does it take into account the difference between a prototype investigation being constantly modified for experimentation and analysis and a production system built to purpose.

0: https://en.wikipedia.org/wiki/W%C3%A4rtsil%C3%A4-Sulzer_RTA9...

Re: Major breakthrough on nuclear fusion energy

#257

Post by regularfry »

reacharavindh wrote: post #107

As an uneducated observer to nuclear physics, I could not tell the significance of this achievement. Did we finally learn how to extract more energy from a fusion rector than we supplied to operate it? Could anyone more in the know here explain in simpler and more practical terms please?

The energy generated is a small red herring here.

For a long time one of the hardest problems in fusion reactor design is what the hell you make it out of. The big win here is that they replaced the walls of the reactor with a new alloy, and it worked according to what theory predicted, which gives them the green light for using that material in ITER.

To simplify a little (ok, a lot) there are two big materials problems inside the reactor. The first is the walls: you need something that's going to survive the temperatures, not disturb the reaction, and not get too radioactive in the process. They previously used carbon, which isn't great: it gets radioactive because it absorbs tritium, which is in the fuel. This experiment used a beryllium alloy, which doesn't absorb nearly as much, and worked, validating the material choice for ITER.

The second problem is to do with the exhaust. You need to get hot plasma out of the chamber without disturbing the ongoing reaction, and with a tokamak that means ridiculously energetic particles hitting a solid divertor. Again, the problem here is what materials you might come up with that stand a chance of surviving useful operational periods. ITER is currently planned to use beryllium walls and a tungsten divertor, but I don't know what JET's divertor is made of at the moment to know whether this experiment will have informed whether tungsten is a good enough choice.

What all this means is that there's one less thing on the "ITER might fail because of..." list.

Re: Major breakthrough on nuclear fusion energy

#258

Post by orangepurple »

khafra wrote: post #182
ambrozk wrote: post #171

Earlier quoted context omitted.

This is a very dumb meme that people use to avoid learning anything about the actual hurdles that are currently being faced by fusion researchers. At some point, fusion will be much less than 30 years away, and at that point, I guarantee you that lazy people will still be repeating this joke, because it is literaly the only thing they know about the subject.

"Fusion is always 30 years away" is a heuristic that almost always works. https://astralcodexten.substack.com/p/heuristics-that-almost...

This is an excellent read, thanks for sharing

Re: Major breakthrough on nuclear fusion energy

#259

Post by spywaregorilla »

dymk wrote: post #212
PaulDavisThe1st wrote: post #186

Earlier quoted context omitted.

> Name a single fusion plant that has been running uninterrupted for years. Minutes, even. Perhaps you meant fission?

No, I mean fusion. The parent comment claims "[Fusion can] provide steady energy without going down for years". I want a single example of this. Meanwhile, we have massive grids of solar and battery being installed _today_, and existing installations replacing coal plants. I'm tired of people talking about fusion (or even nuclear, as it's so mired in public FUD) as if it's some panacea. We have a solution right now:…

We haven't invented commercial fusion power, so none; but theoretically that is how they would function.

Solar and batteries are nice but they're not yet cost effective. They're getting better. But you can't just handwave away real problems from your armchair viewpoint and assume thats all fine.

Re: Major breakthrough on nuclear fusion energy

#260

Post by [deleted] »

pulse7 wrote: post #243
j245 wrote: post #229

Earlier quoted context omitted.

> So they made about 1/4 of the full Tesla Model 3 battery. Focusing on absolute numbers is pretty irrelevant, wouldn’t you say ? We know once we get a working prototype it can be scaled up relatively easily. Strange to see a storage mechanism (battery) compared to a generation mechanism (fusion plant)

So comparison is about the "amount of energy", not about mechanisms...

[deleted]
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