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Major breakthrough on nuclear fusion energy

bbc.co.uk

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Re: Major breakthrough on nuclear fusion energy

#561

Post by hedora »

winrid wrote: post #514
onychomys wrote: post #331

Earlier quoted context omitted.

The 1997 F-150 made 220bhp and got 18mpg [0], while the 2022 F-150 makes 400bhp and 19mpg [1], so fusion is doing way better than that! (...i think i chose comparable trim levels to do that comparison, there are a stunning number of choices there!) [0] https://www.cars.com/research/ford-f_150-1997/specs/103719/ [1] https://www.edmunds.com/ford/f-150/2022/features-specs/

The newer F150 also weighs more. Also, if it didn't have to make twice the power, it would probably get 40mpg today. ICE engines have advanced a lot in 20 years, especially in terms of cost per HP/MPG.

I don't understand why they can't just build a basic pickup truck any more.

We had an old pre-fuel injected pickup. It had a bigger bed than the current truck, and seated six instead of five. It got 33% more miles to the gallon. The new one's transmission likes to overheat, even when not towing.

Seriously, wtf?

Re: Major breakthrough on nuclear fusion energy

#562

Post by elihu »

Terry_Roll wrote: post #559

So are they still using a steam engine to generate the electricity? Will the design of the steam engine working with this reactor be revolutionary?

Probably not. Steam turbines are a pretty mature technology, though I suppose you'd want to use the most efficient kind of turbine available if energy output isn't overwhelmingly bigger than energy input.

edit: since JET is used for research rather than practical power generation, they might not have a steam turbine at all. I was thinking more of the scenario where they're past the research phase and actually doing power generation.

Re: Major breakthrough on nuclear fusion energy

#563

Post by soperj »

dylan604 wrote: post #404
ambrozk wrote: post #344

Earlier quoted context omitted.

The guy's work has directly prevented the deaths of enormous numbers of poor people worldwide. That trumps everything else in my book. Also, don't fall for his wife's PR team. You have no idea why she's divorcing him. Claiming that the issue was Epstein is what any smart legal / publicity team would do in this circumstance.

>The guy's work has directly... The guy's money has funded people who work to do these things.

It's not all his money here. A major chunk of it is Warren Buffet's.

Re: Major breakthrough on nuclear fusion energy

#564

Post by hedora »

Filligree wrote: post #345
Lev1a wrote: post #332

Earlier quoted context omitted.

> What makes you think it will be any more politically viable to scale out than fission reactors? IIRC a major difference would be the danger potential in case of a "meltdown", since a fusion reactor wouldn't have kilograms or even tons of uranium etc. laying around to form another elephant's foot but "just" the irradiated reactor vessel which AIUI is both not as dangerous or as long-lived as fission fuel, a fission…

That is a sane, logical argument. I'm just worried. If sane, logical arguments worked, then there'd be a lot more fission reactors in the world and a lot fewer coal plants.

Yeah; meltdown-proof clean fission reactors have been a solved problem for what, fifty years now?

Re: Major breakthrough on nuclear fusion energy

#565

Post by javajosh »

elihu wrote: post #560
px43 wrote: post #385

Earlier quoted context omitted.

The insane thing that people should realize about the 20T CFS test back in September was that it was them completing the first of 18 coils, and it performed incredibly well. The secret sauce is better high temperature superconductors, and the ridiculous magnets you can build with them. They're pretty much putting these coils together as quickly as they can accumulate the HTSC wiring, and once they have all 18, they b…

ReBCO tape is the specific high-temperature superconducting material they're using. Another important material is FLiBe, which is a liquid that I think absorbs the energy from the fusion reactor. I don't really understand the properties that make it particularly well suited to the task, but I gather it's important. https://en.wikipedia.org/wiki/Rare-earth_barium_copper_oxide https://en.wikipedia.org/wiki/FLiBe

According to the article, FLiBe has the same heat capacity of water, but a boiling point over 14x higher (1430 °C according to the article). Melting point is 359 °C, 3.5x higher. I will speculate that its basically used as a water coolant with the phase shifts shifted up and out. I bet the heat exchangers are exotic, too, having to operate at such high temps! In fact I'd expect to see a pretty sophisticated cascade of exchangers.

Re: Major breakthrough on nuclear fusion energy

#566

Post by chess_buster »

ajuc wrote: post #520
Joeri wrote: post #287

Earlier quoted context omitted.

But nuclear power is also not predictable, as plants regularly experience unexpected downtime. No power source is fully predictable, which is why you need controllable power sources to make up the difference. I would say solar’s problem is controllability. You can only turn it up to the limit of the amount of sun received, which is none at night, and sometimes very little in the day. It remains to be seen how control…

Yes, unexpected stuff happen to baseload powerplants too. Once every year on average maybe? Probably less. If that happens you may need to pay for balancing once a year. Meanwhile solar is unexpected on the scale of minutes to hours, every day. It's not the same.

No its not. https://www.energymeteo.com/products/power_forecasts/wind-so...

Re: Major breakthrough on nuclear fusion energy

#567

Post by gloriana »

moogly wrote: post #175
ppaattrriicckk wrote: post #59

In extension to this news and the press conference, one thing I am super excited about, is the private SPARC project and the MIT-spinoff Commonwealth Fusion Systems (CFS). If you don't know about it already, I would highly recommend checking it out (e.g. by searching YouTube for "MIT Sparc Fusion Reactor" for some fairly accessible videos on the theory behind why they should achieve fusion way faster than the current…

> Theory dictates that with stronger magnets, the reactor can be scaled down (with the square/cube, can't remember exactly), and thus cost and time to develop OTOH, in a tokamak, the plasma volume (and potential energy output) scales quadratically with the torus' aspect ratio (ratio of major to minus radius), so I'm not sure that tokamak-based fusion really is particularly suitable to miniaturization.

However, you as you scale down, all the radiation damage effects per unit volume or unit surface area increase rapidly causing higher material activation and maintenance cost.

Re: Major breakthrough on nuclear fusion energy

#568

Post by btbuilder »

hedora wrote: post #555
bityard wrote: post #516

Earlier quoted context omitted.

The US grid (the last-mile bits anyway) isn't 110 volts, it's 220. It's just our houses that are wired for (mostly) 110 V. Edit: I would love to see some sort of hybrid 110/220 V residential wiring/plug standard take hold in the US. It would require more expensive cable in the walls (since you need one additional conductor) and plugs, but it's totally doable. Most electrical products and appliances made these days ar…

You could just run US-style appliance circuits to your kitchen, etc. Those are sometimes three conductor and other times four conductor. However, I doubt it'd pass inspection if they were easily accessible from the counter-top. If you're going to flout building codes anyway, it'd probably be easier/more practical to just run circuits with foreign outlets instead. Also, it might be easier to find appropriate GFCI brea…

Use 6-15R or 6-20R. I think it would pass inspection because most safety requirements around gfci and afci don’t apply to 240V circuits

Re: Major breakthrough on nuclear fusion energy

#569

Post by willis936 »

nomel wrote: post #470
davidrusu wrote: post #288

A shot of the pulse from within the reactor: https://www.youtube.com/watch?v=IMuOaTqdp4c

Isn't the stream supposed to be in the middle, away from the melty bits?

Yes, but the really hot part is not emitting visible light. ;)

If you're curious about why the bottom glows: ExB drift pushes electrons to the bottom. I'm sure that doesn't make sense, but unfortunately there isn't really a shortcut to understanding here. Some books are pretty accessible though (I'm a fan of The Future of Fusion Energy).

https://ebrary.net/174598/mathematics/drift_motion_energetic...

And, of course, there is always the freely available IAEA textbook:

https://www.iaea.org/publications/8879/fusion-physics

Re: Major breakthrough on nuclear fusion energy

#570

Post by btbuilder »

toast0 wrote: post #539
bityard wrote: post #516

Earlier quoted context omitted.

The US grid (the last-mile bits anyway) isn't 110 volts, it's 220. It's just our houses that are wired for (mostly) 110 V. Edit: I would love to see some sort of hybrid 110/220 V residential wiring/plug standard take hold in the US. It would require more expensive cable in the walls (since you need one additional conductor) and plugs, but it's totally doable. Most electrical products and appliances made these days ar…

There is NEMA 14, which has hot,hot,neutral,ground, but I don't think anything lower than 20amps is available, and that's a locking one, 30 amps is available without locks, but 30 amps at 220v is a lot of power for household outlets. You'd need larger wire in the walls, not just more of them. Any sort of outlet upgrade would need a really good plan for how to make it viable, because even if 100% of new construction u…

I have a 20A 220 circuit for an electric kettle with multiple 6-15Rs. It has a 20A gfci breaker.
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