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Major breakthrough on nuclear fusion energy

bbc.co.uk

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Re: Major breakthrough on nuclear fusion energy

#261

Just to be sure: what we are seeing in the video is plasma from the fusion of hydrogen atoms, right? (And if I'm terribly wrong please don't flame, not a nuclear physics expert here)

Yes, two different isotopes. JET uses deuterium-tritium fuel.

Re: Major breakthrough on nuclear fusion energy

#262
post #88

Earlier quoted context omitted.

In the current economy the funding of these types of projects is usually not the bottleneck. It's finding the people and achieving the actual scientific / engineering breakthroughs. The marginal return on more money is pretty insignificant for that. If you just threw a ton of money at it much of it would probably be splurged or straight away misappropriated. Then you'll get a whole lot of terrible press, undermining…

I don't believe that is true. This famous chart shows funding levels versus requested since the 1970s: https://images.app.goo.gl/58YdLFt7R9uY8dyR6 The much maligned prediction that fusion is 30 years away was always anticipating stronger financial support.

Thanks for that chart. Maybe famous, but first time I've seen it. It's a bit pathetic. And explains a lot about progress.

Re: Major breakthrough on nuclear fusion energy

#263

According to Wikipedia (German) the Wendelstein 7-X already did 150 mega joules of "sustained fusion" [1]. So how is this record breaking? [1]: https://de.wikipedia.org/wiki/Wendelstein_7-X

Wendelstein 7-X is for plasma science, it is not intended to fuse anything.

Re: Major breakthrough on nuclear fusion energy

#264
post #251

Earlier quoted context omitted.

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.

I was just talking about this the other day, its formal name is called the Wait Calculation https://en.wikipedia.org/wiki/Interstellar_travel#Wait_calcu...

Re: Major breakthrough on nuclear fusion energy

#266
post #87

Earlier quoted context omitted.

It's 30 years time. It's always 30 years time. https://www.discovermagazine.com/technology/why-nuclear-fusi...

I think it used to be in 20 years time. https://bigthink.com/videos/fusion-really-is-20-years-away-2...

Inflation.

Re: Major breakthrough on nuclear fusion energy

#267
post #199

Earlier quoted context omitted.

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 betwee…

Yes, I probably should have used numbers from a large diesel rather than an automobile engine. Wow, the Wärtsilä-Sulzer RTA96-C operates at speeds as low as 15 RPM! That is just mind-boggling. I found this video:

https://www.youtube.com/watch?v=jXHvY-zY9hA

Still, I think you will find that even this doesn't help all that much. A cycle time measured in seconds rather than milliseconds is still orders of magnitude away from what can presently be achieved.

> the difference between a prototype investigation being constantly modified for experimentation and analysis and a production system built to purpose.

AFAICT, no one has ever built an ICE that is within even an order of magnitude of realistic operating parameters of a fusion ICE. It's a whole 'nuther level of engineering challenge beyond just getting the fusion itself to work. I'm not saying it's impossible, but I'll give you long odds against seeing it happen in any of our lifetimes.

Re: Major breakthrough on nuclear fusion energy

#268
post #44

They're still a very long way from getting a net gain in energy: https://youtu.be/LJ4W1g-6JiY

Sadge. But I think this is the best bet for sustainable and clean energy, so why not put all the enthusiasm we can into it? A breakthrough is a breakthrough, and that's good news.

Going in the wrong direction with development that can never work as intended is always a waste no matter how good the goal. Incorrectly reporting this modest incremental change is the kind of thing that allows doomed projects like this to consume vast resources of money, material and skilled labor that could be used to explore other alternatives.

Re: Major breakthrough on nuclear fusion energy

#269

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.

that's perfect analogy, since most fruit & nuts are multi-generational projects.
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