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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

#41

Post by fizigura »

ladams wrote: post #9
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

Stellarators in particular suffer from very long development cycles. It takes years and years of research to develop the algorithms used to optimize the coil geometries, and then the production of the coils and assembly of the vacuum vessel within the coils is much more challenging than for a tokamak. The coils are hard to produce because they have highly irregular shapes, and tight tolerances. Assembling the vacuum…

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.)

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

#42

Post by 2-718-281-828 »

karmajunkie wrote: post #30

This is perhaps an obvious question to some, but I'll ask it anyway: How is the power generated here converted into usable electricity? I know for conventional fission reactors the heat of fission is basically used to run a steam turbine. Given the extreme heat of the plasma, and that it must be magnetically suspended so that it doesn't even touch the sides of the containment, how is that heat transferred to some oth…

probably boiling water and the steam drives turbines whose coils and rotating magnets produce electricity.

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

#43

Post by fizigura »

t0mas88 wrote: post #28
aeyes wrote: post #11

Earlier quoted context omitted.

In the German Alternativlos podcast the Wendelstein team (Prof. Dr. Thomas Klinger, Dr. Adrian von Stechow) recently stated that it is already feasible, they estimate a cost of ~€20B and a 5 year construction time for a commercial fusion power plant if we started now. https://alternativlos.org/51/

For less than 15 billion euro you could buy enough solar to power a country the size of the Netherlands. With 5 billion to spend on batteries you might even make it through night time usage. Or in other words: Fusion is too expensive at this point to be useful.

The same was said 20 years ago about solar power.

Then some countries stepped up the subsidies game and booom, prices fell dramatically since suddenly everybody wanted a piece of the cake. And competition drove this all down.

All you need is for somebody to start. Or we just keep telling ourselves that it's too expensive, shrug, and move on.

Also note how the goal posts changed. Until recently, everybody made fun of fusion by basically saying it's too hard, it's too far in the future. Now it's not too hard anymore, it's just too expensive. What's next? Too loud? Too big? Induces headaches with the esoterically minded?

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

#44

Post by jeffbee »

WJW wrote: post #36
karmajunkie wrote: post #30

This is perhaps an obvious question to some, but I'll ask it anyway: How is the power generated here converted into usable electricity? I know for conventional fission reactors the heat of fission is basically used to run a steam turbine. Given the extreme heat of the plasma, and that it must be magnetically suspended so that it doesn't even touch the sides of the containment, how is that heat transferred to some oth…

Given that the plasma is several million degrees, it will radiate a lot of energy and heat up the walls even if it does not directly touch them. Just cooling the walls can heat up the cooling fluid enough to later produce steam with. AFAIK the Wendelstein machine is not configured for electricity production though, so the cooling is just cooling atm.

> Given that the plasma is several million degrees, it will radiate a lot of energy

That doesn't entirely follow. 2 particles whizzing past each other at relativistic speeds have extreme temperatures but don't offer much energy. Mass is in this equation.

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

#45

Post by idiotsecant »

karmajunkie wrote: post #30

This is perhaps an obvious question to some, but I'll ask it anyway: How is the power generated here converted into usable electricity? I know for conventional fission reactors the heat of fission is basically used to run a steam turbine. Given the extreme heat of the plasma, and that it must be magnetically suspended so that it doesn't even touch the sides of the containment, how is that heat transferred to some oth…

Yes, the boring and actually feasible answer is steam.

But it sure is fun to dream!

https://en.wikipedia.org/wiki/Direct_energy_conversion

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

#46

Post by fizigura »

KyleBerezin wrote: post #18
aeyes wrote: post #11

Earlier quoted context omitted.

In the German Alternativlos podcast the Wendelstein team (Prof. Dr. Thomas Klinger, Dr. Adrian von Stechow) recently stated that it is already feasible, they estimate a cost of ~€20B and a 5 year construction time for a commercial fusion power plant if we started now. https://alternativlos.org/51/

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.

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

#47

Post by Eji1700 »

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.

I'm honestly not sure if you're joking but in case you're not, the "minimum viable size" is hardly the largest issue with what you're proposing and it sounds like you're not getting what the key issues are.

You're talking about taking a technology that's so finicky we've barely gotten it to work after almost 100 years and rocketing it into space? We're no where near good enough at this to get a test that would work after the extreme violence of an escape velocity launch.

Further fusion reactors aren't like fission. "exploding" really isn't a problem . Keeping the reaction going in an efficient manner is.

IF exploding was a problem, space is probably the worst place for it? Putting it way underground would be vastly easier and a hell of a lot safer because you won't have material possible falling back to earth/hitting satellites in orbit.

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

#48

Post by jtriangle »

karmajunkie wrote: post #30

This is perhaps an obvious question to some, but I'll ask it anyway: How is the power generated here converted into usable electricity? I know for conventional fission reactors the heat of fission is basically used to run a steam turbine. Given the extreme heat of the plasma, and that it must be magnetically suspended so that it doesn't even touch the sides of the containment, how is that heat transferred to some oth…

Same way most electricity is made, you use the energy created to heat up water into high pressure steam, high pressure steam turns a turbine(s) which turn gensets that produce 3 phase AC current.

This one in particular isn't setup to do that, and as far as I know, none are yet. It's a pretty simple engineering problem, and, until we can maintain fusion for months at a time, it's not really something that needs to be built.

There is, however, one fusion concept that shows some promise that doesn't require all that that helion energy is developing (helionenergy.com) they're yet to create net-power, but, their idea has some promise, and avoids the common problems with other forms of fusion power. I don't really see it as the be-all to end-all in the space, but from what I can tell they very well might be the stopgap that is needed between large scale stellerators and fission.

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

#49

Post by fizigura »

anonuser123456 wrote: post #22

I don’t get it; who cares? We know the equations to burn plasma; that’s the easy part. The hard part is building a machine that can burn plasma and breed tritium at appreciable rates. Why even bother with these machines that can never be built economically?

We know the equations for flight. Why didn't they just build a 787 in the 40s already?

Oh, is it because the technology didn't exist and first had to be developed, in incremental refinements? Initial airplanes didn't even fly and half the people trying them died? Oh...

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

#50

Post by tboughen »

tootie wrote: post #33
KyleBerezin wrote: post #25

Earlier quoted context omitted.

Haha, no I am just some random guy who reads too many Wikipedia articles. "Electromagnetic plasma containment folding" does sound like something a crazy person at a bus station would rant about. My explanation was definitely over simplified, but I'm not knowledgable enough to go into detail on the topic. I can't even point you towards something to read on the topic since everything I read about it is like 15 years ol…

If a Hollywood screenwriter were naming a crazy science device, they would come up with something like Wendelstien 7-X

My favourite fact about it comes from https://phys.org/news/2016-02-plasma-physicist-discusses-wen...

“…the supporting structure can only withstand the forces if the interfaces between the ten individual segments of the central rings, which weighs several tonnes, are built with a level of precision of less than 100 millionths of a metre…” - and they found a small family business in the north of Italy capable of doing this!

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