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Major breakthrough on nuclear fusion energy

bbc.co.uk

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Re: Major breakthrough on nuclear fusion energy

#541

Post by willis936 »

faeyanpiraat wrote: post #533
DennisP wrote: post #496

Earlier quoted context omitted.

We're not that far off. JET previously achieved Q=0.67, ie. two-thirds as much energy output as input. (The new result has higher output but lower Q.) For a practical reactor we need Q around 30, which might seem far away but tokamak output scales with the square of reactor volume and the fourth power of magnetic field strength. Double the field, 16X the output, and we can generate much more powerful magnetic fields…

So they just need to build the same thing, but make it gigantic in size? Why is it not yet done?

It is very expensive to do.

HTS was known but not practical when ITER was planned, but it's almost done. ITER is almost large enough to be an LTS-based power plant.

ITER will still produce a lot of useful science, but there is a now a potential class of mid-scale HTS machines that would help develop plasma models.

These iterations seem frustrating and time consuming, but their results are lowering the cost of a hypothetical power plant until one day maybe society will decide they're worth making for power generation.

Re: Major breakthrough on nuclear fusion energy

#542

Post by Gadiguibou »

openknot wrote: post #368
Gadiguibou wrote: post #283

I really appreciate the note of the environmental analyst which helps readers who don't have deep knowledge of the field understand the meaning of this breakthrough in context. I wish more news agencies adopted the same practice.

The Financial Times, though pricey as a financial newspaper, is a good source for this. It regularly publishes in-depth articles with a wide range of interviews with experts for readers to learn the context of current issues (via their "News in-depth" series, and also their series called "The Big Read").

Thanks for the tip!

Re: Major breakthrough on nuclear fusion energy

#543

Post by [deleted] »

faeyanpiraat wrote: post #533
DennisP wrote: post #496

Earlier quoted context omitted.

We're not that far off. JET previously achieved Q=0.67, ie. two-thirds as much energy output as input. (The new result has higher output but lower Q.) For a practical reactor we need Q around 30, which might seem far away but tokamak output scales with the square of reactor volume and the fourth power of magnetic field strength. Double the field, 16X the output, and we can generate much more powerful magnetic fields…

So they just need to build the same thing, but make it gigantic in size? Why is it not yet done?

[deleted]

Re: Major breakthrough on nuclear fusion energy

#544

Post by lisper »

exitheone wrote: post #531
lisper wrote: post #208

Earlier quoted context omitted.

Yes, that is exactly the problem. If they are ever going to be commercially viable they need to become typical. 59MJ per cycle isn't going to do you a lot of good if a cycle time is measured in months as is currently the case. You have to get that cycle time down to fractions of a second at this energy level before you even have a chance at commercial viability. 59 MJ is a tiny amount of energy by the standards of co…

I hope you realize that these are research reactors that are not designed to give you a low interval between cycles or produce power. They are meant so clarify some of the open research questions for the likes of ITER/DEMO that will integrate these findings into things that are actually designed to produce a lot more power quicker.

Yes, of course I realize that. I hope you realize that even if they get these research reactors to work (which is far from given) that there will still be a shit ton of work to be done before this technology can be used to produce commercially viable power.

Re: Major breakthrough on nuclear fusion energy

#546

Post by willis936 »

ninkendo wrote: post #528
willis936 wrote: post #320

Earlier quoted context omitted.

I'm confused. What do you think the goal of the campaign was?

It's tough to say because the campaign is a signpost on the way to an eventual end goal. But the end goal is easy to describe: "a working fusion power plant." The end goal is so far away at this point, not a single player in this space is even trying to do it, even on their farthest-out roadmaps...

No, the campaign's goals were to push higher plasma energy out of a JET pulse. This required upgrades to many subsystems and to dust off everything necessary for nuclear operations.

They did this in support of ITER, but there are also likely other political motivations. There has been no nuclear MCF operation on Earth in decades and now the UK has invested in resuming theirs rather than mothballing it.

You can't make claims about the motivations of the campaign (such as it being a signpost?) if you don't know what was even done.

And again, you shouldn't talk about the roadmaps if you haven't looked at them. Look at PPPL FIRE and power plant studies.

Re: Major breakthrough on nuclear fusion energy

#547

Post by selimthegrim »

jackfruitpeel wrote: post #534
bityard wrote: post #526

Earlier quoted context omitted.

Ireland is #2? As a culturally ignorant American, that _does_ surprise me.

We are absolute fiends for tea.

The box of Barry’s in my drawer (I’m in America) agrees with you

Re: Major breakthrough on nuclear fusion energy

#549

Post by brandall10 »

onychomys wrote: post #331
ClumsyPilot wrote: post #307

Earlier quoted context omitted.

"with very expensive and massive fission reactors" The laws if physics don't owe us a free lunch. Light, safe and cheap powersource does not exist Fossil fuels aren't a power source, they wre a power store - that power was collected and millions of years ago. Also 100% productivity on 25 years is quite good - what did combustion engines improve in that time, 5%?

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/

Mileage figures have little to do w/ max power. That mileage figure is roughly using the same actual power, which is a relative sip of fuel.

The main difference would be in testing EPA methodology which which would be a bit more stringent/realistic to world use. On top of that, there likely is more rolling resistance at lower speed due to larger tires and heavier weight, offset somewhat by lower C/D at speed.

Basically it's hard to extrapolate ICE efficiency gains... they're there are sure, but probably in the single or low double digits.

Re: Major breakthrough on nuclear fusion energy

#550

Post by danenania »

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's also good to have a number of these things in the oven, because it's hard to predict when a sudden discontinuous leap might make practical in the short term something that previously seemed like a multi-generational project.

I presume almost no one in 1920 could have imagined that anything approaching the output of fission energy would become common in their lifetime.

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