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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

#291

Post by angiosperm »

pfdietz wrote: post #99

I greet W7-X with a huge yawn. A reactor based on stellarators will still be very large and have very low volumetric power density. The beta is not good, so these would only work with DT, and suffer from the generic problems of all DT schemes.

Right. It is fun to keep plasma hot for a long time, but literally none of the fusion projects being worked on can ever lead to production of so much as one solitary erg of commercial power. Cost will necessarily be much more than for fission. Fission is far from competitive today, and falling farther behind daily.

There is a bare possibility of eventual usefulness for spacecraft propulsion. And, some spinoff might come out of a newfound ability to handle lots of hot plasma. Maybe for sewage treatment?

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

#292

Post by angiosperm »

audunw wrote: post #223
gregfjohnson wrote: post #178

Question for this knowledgeable group of people: Which fusion start-ups look promising? How does inertial confinement look? Any thoughts on the newly funded start-up Blue Laser Fusion? Any thoughts on one of the older players, TAE? How about Commonwealth? Helion? Others?

I think Helion is most promising for two reasons. 1. Even if the more traditional fusion power plants manage to generate the plasma itself in a device that’s not too expensive (big if) it seems that just the heat exchange mechanism itself would be extremely complicated and expensive. And since they’re thermal power plants you’re limited in where you can put them and how big they must be to be economical. 2. As CO2 em…

I used to think Helion might have a chance, until I looked into the energetics graph. At the temperature they hope to operate, a deuterion would much rather fuse with another deuterion, producing a neutron, than with a helion.

And Helium3 is not available in useful quantity. No, not even on the moon.

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

#293

Post by angiosperm »

fizigura wrote: post #46
KyleBerezin wrote: post #18

Earlier quoted context omitted.

Yea, but compare the financial burden of that compared to a solar farm of the same output. Not to mention the technical risk.

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.

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

#294

Post by angiosperm »

bmicraft wrote: post #127
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.

No, solar farms in the desert with a HVDC lines obviously.

The desert is the worst place to put a solar farm. Hot, dusty, far away.

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

#295

Post by angiosperm »

gregfjohnson wrote: post #178

Question for this knowledgeable group of people: Which fusion start-ups look promising? How does inertial confinement look? Any thoughts on the newly funded start-up Blue Laser Fusion? Any thoughts on one of the older players, TAE? How about Commonwealth? Helion? Others?

Literally none of the projects running will ever lead to so much as a single erg of commercial power. They might spin off interesting plasma materials-processing tech.

It would be much more expensive to build a fusion power plant than a similar-capacity fission plant, but fission is already uncompetitive, and falls farther behind by the day. Start thinking hard about uses for stable contained plasma that doesn't fuse. Advantage is, it doesn't need to be especially hot. What they have already is more than hot enough for any plausible use.

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

#296

Post by atoav »

foolfoolz wrote: post #2

i’ve been following this project for 10 years. it’s been successful. but how do projects like these move faster? the wendelstein 7x is never going to generate usable electricity. it’s supposed to be the pre cursor to the producing reactor

In the (German) podcast alternativlos two nerds interview the Wendelstein 7-X people and ask them specifically what stops them from moving faster and their answer was: money.

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

#297

Post by Halfwhit »

dmm10 wrote: post #264
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…

With powder bed printers overhangs and detached captured parts aren't a problem. Try making your own from an old inkjet printer.

Where could someone interested in doing this learn more?

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

#298

Post by sdwr »

Eji1700 wrote: post #81
sdwr wrote: post #74

Earlier quoted context omitted.

That was not a real question, it was a subconscious plea for elon musk to take over and make it work. "Shooting it into space" is a reference to how SpaceX disrupted the rocket industry through a "fail fast" mentality, aggressive goals, and sheer force of will.

This take is even more baffling to me than the original question.

Let me break my logic down:

Assumptions:

---------------------

1. The average commenter here (me!) knows a little about nuclear fusion, and a lot about online tech news.

2. There are no new ideas.

Background:

------------------------

This big science project is overbudget, making incremental progress, and the timeline is stretching to forever.

That is incredibly similar to the state of rockets 10 years ago - publically funded, making little progress.

Leap of logic:

-------------------------

Somewhere in his subconscious, OP pattern-matched to the only big successful science project in the news recently - SpaceX.

But the subconscious no good at talky talky, and OP didn't trace the train of thought, so what came out was "Shoot them into space".

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

#299

Post by eternityforest »

rkagerer wrote: post #242
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…

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)

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

#300

Post by jjk166 »

midasuni wrote: post #70
idiotsecant wrote: post #45

Earlier quoted context omitted.

Yes, the boring and actually feasible answer is steam. But it sure is fun to dream! https://en.wikipedia.org/wiki/Direct_energy_conversion

Isn’t one of the problems with nuclear that it increases water temperature in rivers

The reverse actually. Reactors need to be shut down when rivers get too warm because they are not able to properly cool the reactor. Nuclear reactors don't produce anywhere near enough energy to heat a large river by a measurable amount.
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