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Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

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Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#301

Post by dTal »

yoz wrote: post #283
dylan604 wrote: post #179

Earlier quoted context omitted.

I didn't either, since I spelled it Warf! I never watched Star Trek (probably get my HN privileges revoked for that), but I did know that much. And then the Reading Rainbow guy's "whatever happened will happen again". I know the character's name is Geordie or whatever, but he didn't have the right accent for him to be a Geordie, so he will forever be Reading Rainbow guy instead.

> I know the character's name is Geordie or whatever, but he didn't have the right accent for him to be a Geordie it’s a fair demand to make, given that his TV predecessor was called Scotty and DID have a Scottish accent

I can't believe I've gone my entire life without noticing the obvious wordplay... even after seeing the Futurama parody with "Welshy"!

Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#302

Post by dTal »

waterheater wrote: post #80
white_dragon88 wrote: post #10

Earlier quoted context omitted.

You know enough to say more. Say more!

I'm not that guy, but I can speak to what you're asking. I've followed Wendelstein 7-X for almost a decade. Nuclear fusion occurs at extremely-high temperatures. As you heat your fusion fuel to sufficiently-high temperatures to allow fusion, the matter transitions into a plasma, which is great: plasmas react to electromagnetic fields. As such, a major challenge with achieving viable nuclear fusion is making a vessel…

>Also, he3 is plentiful on the surface of the moon, so mining the surface of the moon will be performed to obtain the required fuel, which is the fundamental premise of the movie "Moon".

This is repeated a lot, but the practicalities are... questionable. Here's an article I consider to be the definitive criticism of the concept:

https://www.thespacereview.com/article/2834/1

Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#303

Post by osi »

egypturnash wrote: post #216
fastball wrote: post #199

Earlier quoted context omitted.

Genuine question: why? That isn't even a song, it's just a vinyl record skipping for a minute and a half.

It's two copies of "...where time becomes a loop." One on the left, one on the right. One of them is slightly shorter than the other, so that as they repeat again and again, they slide in and out of phase. The track ends after they come back into phase. If you listen to this with headphones, or speakers with decent separation, paying attention to this feels interesting. It's similar to the way listening to "binaural…

bravo sir very well explained.

Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#304

Post by greesil »

hedora wrote: post #38
Eji1700 wrote: post #6

Earlier quoted context omitted.

Mostly, they don't? There should be more funding in this area, but at some point you've got to build it, and that takes a ton of time. Regulations/bureaucracy could be better but at the end of the day you're not going to cut off a ton of time safely. Once you have a working model iteration gets much much faster, but we've simply been hitting walls for decades.

Is there a minimum viable size for a fusion reactor? If it scaled down ennough, they could just launch prototypes into space, and see if they explode.

Yeah there is, at least for a tokamak. The smaller the device, the stronger the magnets need to be, otherwise you can get instabilities that will prevent the plasma from being contained. This is why commonwealth fusion is building their own superconducting magnets, for example.

Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#305

Post by nomel »

oefnak wrote: post #213
nomel wrote: post #194

Earlier quoted context omitted.

Coming from 3d sculpting to CAD was...eye opening. It really makes you realize how much of design constrained by the CAD tools, which are mostly constrained by manufacturability. If true 3d printing* ever gets cheap, it'll be interesting to see how much form will be able follow function, rather than manufacturing cost. * true 3d, as in overhang are allowed. Something like a cheap FDM is more 2.5d, since overhangs are…

You can print with supports to print any shape.

Yea, but this requires soluble supports, without joined parts/assembly.

Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#306

Post by [deleted] »

eternityforest wrote: post #237
nomel wrote: post #194

Earlier quoted context omitted.

Coming from 3d sculpting to CAD was...eye opening. It really makes you realize how much of design constrained by the CAD tools, which are mostly constrained by manufacturability. If true 3d printing* ever gets cheap, it'll be interesting to see how much form will be able follow function, rather than manufacturing cost. * true 3d, as in overhang are allowed. Something like a cheap FDM is more 2.5d, since overhangs are…

Overhangs up to 45 degrees work fine, and usually steeper. Bridges also work, most of the time, although I am having trouble with them at the moment. They're not quite unconstrained, and the layer adhesion strength makes some geometries not strong, but they're much more than 2.5D.

[deleted]

Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#307

Post by [deleted] »

eternityforest wrote: post #299
rkagerer wrote: post #242

Earlier quoted context omitted.

Well, there's SLS which is tolerant of overhangs and other exotic features. Formlabs has a machine in the 5 digit price range, and I wouldn't be surprised to see competitors come out with a 4-digit one in the near future.

You could probably build a 4-axis FDM machine for less than that too, which might be better for average users(No powder mess)

[deleted]

Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#308

Post by fizigura »

pfdietz wrote: post #149
fizigura wrote: post #46

Earlier quoted context omitted.

Solar farms on farmland? That won't scale to the energy needs of 8bn+ people if we still want to keep feeding them. Especially a non-vegetarian diet.

Where did he say on farmland?

Well, most land is either farmland, forest or desert. Forest is out of the question for any solar installations unless you want to cut down the trees. Desert is not easily accessible for most parts of the world and provides terrible conditions for solar cells that have sharply declining efficiency with heat and don't like dust.

Leaves farmland, if you want to do this kind of thing at any sort of required scale. (Sure you can put solar cells on barn roofs, but the premise was scale magnitudes beyond that.)

Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#309

Post by fizigura »

angiosperm wrote: post #293
fizigura wrote: post #46

Earlier quoted context omitted.

Solar farms on farmland? That won't scale to the energy needs of 8bn+ people if we still want to keep feeding them. Especially a non-vegetarian diet.

Hint: solar on farmland does not interfere with use as farmland. Look up agrivoltaics. Solar on pasture is even easier, and protects livestock from weather extremes.

Farmland is literally converting solar energy into sugars. It's natures solar plants. Sure, you can get a bit of shade for your cattle. But the hundreds of millions of acres used for crops are directly competing for sunlight with your solar cells.

Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#310

Post by fizigura »

Guvante wrote: post #54
fizigura wrote: post #41

Earlier quoted context omitted.

For a few billion USD you could build a real power plant of this type. Sounds expensive, but consider how much money nuclear fission did cost initially, and how much money we burn on other stuff, then it's not unthinkable to have somebody rich chip in and make it happen. (Germany just gave $10bn subsidies for a domestic Intel factory.)

They managed to handle what a fission reactor outputs every second in this experiment. I don't think that points to a commercial reactor whenever someone spends a few billions.

That's how research works. The first fission experiments couldn't power half a small country either.

When you listen to the guys from this original article then you'd know that for 10-20bn USD you could likely build a real power plant with this tech within 5 years. It's obviously not without risk, which is why nobody is doing it. But the technical feasibility is there.

They also point out that once the first-of-a-kind installation exists, subsequent models will be way cheaper and way better since you'd have learned a lot and streamlined the process.

But we choose to use public money for fossil subsidies instead, cause jobs, or something.

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