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Revamped German stellarator should run longer, hotter and compete with tokamaks

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Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#111

Has anyone published research on concepts for a stellarator that uses high field magnets like the SPARC/ARC systems? Obviously the idea is that it would be smaller, but I am curious if there are any interesting specifics for such a machine. You could imagine that if W7-X and SPARC show good results in the next 5 years then a high field stellarator design would start to look pretty interesting.

Both Type One and Renaissance (mentioned in the article) are HTS stellarator startups. I'm not sure if they've published power plant studies, but they've certainly pitched them.

Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#112
post #92

Earlier quoted context omitted.

Well fusion reactors are likely to cost a huge amount of money when they do become operational. No point having them sinking in a storm. Probably just safer to charge a huge battery and put it on a ship (if you don’t want to use fossil fuels). Avoids a lot of unfoseen commercial risk. Even though you could use water for shielding, the metal container and other things that hold the reactor would be highly radioactive…

> Probably just safer to charge a huge battery and put it on a ship Large container ships burn through 16 tons of bunker oil per hour, and each journey can last up to 3 weeks - any idea what size of battery such a ship would need? I have no clue how to calculate that), but I'm guessing it would be completely impractical, even if we made huge strides in battery energy density.

here fuels like hydrogen might make sence, but why not 'normal' nuclear?

There are hundreds of nuclear powered ships already - submarines, Icebreakers, carriers, etc.

Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#113
post #92

Earlier quoted context omitted.

> Probably just safer to charge a huge battery and put it on a ship Large container ships burn through 16 tons of bunker oil per hour, and each journey can last up to 3 weeks - any idea what size of battery such a ship would need? I have no clue how to calculate that), but I'm guessing it would be completely impractical, even if we made huge strides in battery energy density.

here fuels like hydrogen might make sence, but why not 'normal' nuclear? There are hundreds of nuclear powered ships already - submarines, Icebreakers, carriers, etc.

>There are hundreds of nuclear powered ships already - submarines, Icebreakers, carriers, etc.

Aren't they all operated by militaries though? So if a conspiracy of crew members tries to steal some enriched fuel or fission products, it is legal to just shoot them or throw them in jail for decade for trying.

Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#114

Has anyone published research on concepts for a stellarator that uses high field magnets like the SPARC/ARC systems? Obviously the idea is that it would be smaller, but I am curious if there are any interesting specifics for such a machine. You could imagine that if W7-X and SPARC show good results in the next 5 years then a high field stellarator design would start to look pretty interesting.

Both Type One and Renaissance (mentioned in the article) are HTS stellarator startups. I'm not sure if they've published power plant studies, but they've certainly pitched them.

Ah great thank you! I only scanned the article. I will see if they have published anything.

Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#115
post #59

Earlier quoted context omitted.

We've already given it more than 50 years.

But apart from the part that's useful for nuclear weapons research, we've barely given it any funding. The idea of "we could have useful fusion reactors in 30 years" always came with the sentence "if we get the funding to do it". There's this [1] famous graph comparing US research spending into Fusion, compared to 1976 predictions how long it would take with different budgets. According to that, the US funded fusion…

That famous graph was for a crash program for tokamaks, and it was predicated on tokamak physics working much better than it turns out it does. If that program had been funded it would have been a guaranteed failure. It would probably have been a failure even if the physics had been favorable, for engineering reasons that didn't become a point of public controversy until the 1980s.

Also, I think you have causality reversed. Fusion isn't remote because of lack of funding; rather, funding was low because there weren't stakeholders pushing for it, and that was because the stakeholders didn't see any value coming from it. For example, all the reactor designs utilities had been presented with were not things they had any interest in building, they were too large, complex, and expensive.

Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#116

Earlier quoted context omitted.

> And it would face the same showstoppingly bad volumetric power density as tokamaks, because of limits on that energy flow through the surface of the reactor. I do think it is worth persevering though. The future of energy is Solar/Wind but Fusion should not be ignored. It is one of Nature's fundamental processes. Mastering fusion could turn out to be useful in ways we cannot possibly fathom at the moment right now.

We already have the perfect way to create heat and the science around it has been long solved and understood. Solar and wind won't save us and fusion certainly won't. It amazes me how solar and wind dreamers all seem to like fusion but fission is just super evil.

Why won't solar and wind save us? There are many bogus reasons people give for that (IMO incorrect) opinion; I'm wondering which one you're going to come up with.

Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#117

Just like COVID helped the mRNA/CRISPR technology evolve and come faster and closer to us, with the potential for many more usages in various diseases, I hope that the ongoing/coming energy crisis will help all nuclear fusion technologies tokamak/stellarator become real. We’re still a few years away from having them in actual power plants and a few decades away from solving our energy problems for every, but I hope w…

Fusion is about as relevant to energy production as deep sea submarines are to commuter transport. There's no way to get heat out of one and turn it into electricity in a way that is practical enough for power generation even if the core technologies were here today rather than 30 years after we need to fix things.

We have the solution, it's removing the most egregious wastes of energy and using the sun to power the rest. It's the same solution that we've always had available, we just have to do the intelligent thing rather than the thing which gives more power to the powerful.

Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#118
So for those of us who just want fusion without the physics explanations; is there any possibility a stellerator could actually give us a net Q (including -all- the power put into the process, and not just point of fusion) ? or is it just a good place to run fusion experiments?

Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#119
post #91
post #53

Earlier quoted context omitted.

DT fusion would be just ridiculous for space flight. Anything a DT reactor could do a fission reactor could do much better -- much smaller, much higher power density, much less complexity. And similarly for use in ships down here on Earth. In practice, synfuels would be better than either for ships on Earth.

I don't understand this; if fission reactors were "better", we wouldn't be pouring so much into fusion? Also, if it makes a difference, I didn't mean we'd be bolting a first gen tokamak to a container ship; I meant, much later down the line, if we were able to miniaturise (similar to how we have nuclear powered subs and ice breakers).

Much more money is "poured into" fission than fusion, likely by a few orders of magnitude. There's one mega project around fusion (ITER) that has a price tag of about 1-2 billion dollars a year if you average it out over the many-decade life of the project, while any given fission plant built also costs billions of dollars.

Like, whether or not fusion itself is a "meme," the idea that we spend obscene amounts of money on it is absolutely a meme with no real backing in reality.

The appeal of fusion is really more about getting out of worrying so much about meltdowns and weapon proliferation, and that there is potential for much higher overall energy output if we can figure it out.

That last bit is why, imo, we should be investing in it now even though it won't really help us reach net zero carbon "in time". If we want to reverse our carbon impact, if and when we get to net zero, we're going to need immense amounts of energy to do it.

Re: Revamped German stellarator should run longer, hotter and compete with tokamaks

#120
post #91

Earlier quoted context omitted.

I don't understand this; if fission reactors were "better", we wouldn't be pouring so much into fusion? Also, if it makes a difference, I didn't mean we'd be bolting a first gen tokamak to a container ship; I meant, much later down the line, if we were able to miniaturise (similar to how we have nuclear powered subs and ice breakers).

Much more money is "poured into" fission than fusion, likely by a few orders of magnitude. There's one mega project around fusion (ITER) that has a price tag of about 1-2 billion dollars a year if you average it out over the many-decade life of the project, while any given fission plant built also costs billions of dollars. Like, whether or not fusion itself is a "meme," the idea that we spend obscene amounts of mone…

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