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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

#141

Post by midoridensha »

ak217 wrote: post #23
dleslie wrote: post #6

Forgive my ignorance; what with all the effort made to isolate the exceedingly hot plasma from connecting with any surface, what are the plans to extract the heat in order to generate power?

By capturing neutrons (which, not being charged, escape the magnetic confinement continuously as the reaction goes on) with a moderator blanket which is then cooled with water/steam. How to keep the blanket from quickly degrading and becoming nuclear waste seems to be an open problem (not too different from what goes on in fission reactors though) https://en.wikipedia.org/wiki/Fusion_power#Energy_capture

It's too bad no one's figured out a way to capture the output of a nuclear reaction and convert it directly to electricity without the intermediate heat cycle. Instead, most of the energy generated is just waste heat, and only a fraction of the energy generated is used for something useful.

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

#142

Post by Bombthecat »

snovv_crash wrote: post #34
homarp wrote: post #9

https://www.energy.gov/science/doe-explainsstellarators A stellarator is a machine that uses magnetic fields to confine plasma in the shape of a donut, called a torus. Over tokamaks, the other main technology that scientists are exploring for fusion power, stellarators require less injected power to sustain the plasma, have greater design flexibility, and allow for simplification of some aspects of plasma control. Ho…

Stellerators aren't really in a torus, they are in a weird fractally twisted torus, sort of like a many-twisted Mobius strip. You really need to see a picture to understand.

I would say,it's like a roller coaster in a donut?

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

#143

Post by stormbrew »

ncmncm wrote: post #134
stormbrew wrote: post #119

Earlier quoted context omitted.

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…

Some people quite reasonably object to spending billions of dollars every year on a project with a vanishingly small prospect of success, and of exactly zero practical value if it ever did succeed. There will never be so much as a single kWh of commercial power from these turkeys. We can all think of numerous projects going unfunded that would have much higher chances of success, and much greater positive impact. But…

> We can all think of numerous projects going unfunded that would have much higher chances of success

I can think of far more things getting funded that are either even less likely to succeed or likely to succeed and, in so doing, will cause harm and death to many people. There are so many things we're spending so much money on that do nothing but harm it's absurd to laser focus on something you consider merely pointless as a Boogeyman.

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

#144

Post by ClumsyPilot »

hollerith wrote: post #113
ClumsyPilot wrote: post #112

Earlier quoted context omitted.

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.

I believe this was never attempted.

On board the ship itself, all the nuclear material is inside a running reactor, any would-be criminal would be dead before you could shoot them

Russian nuclear icebreakers are civilian ships, and people working at normal nuclear power stations are civilians too.

It is actually only relevant what happens in the part of the chain that handles nuclear fuel - thats the shipyard plus processing of spent fuel. But again, we do that for powerplants already.

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

#145

Post by ncmncm »

okasaki wrote: post #139
ncmncm wrote: post #137

Earlier quoted context omitted.

In other news, the UK government revealed it is wholly disconnected from reality.

Yeah ok, or maybe you don't know what you're talking about.

Taking British ministerial announcements at face value has not worked out well for many, over recent decades.

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

#146

Post by ncmncm »

stormbrew wrote: post #143
ncmncm wrote: post #134

Earlier quoted context omitted.

Some people quite reasonably object to spending billions of dollars every year on a project with a vanishingly small prospect of success, and of exactly zero practical value if it ever did succeed. There will never be so much as a single kWh of commercial power from these turkeys. We can all think of numerous projects going unfunded that would have much higher chances of success, and much greater positive impact. But…

> We can all think of numerous projects going unfunded that would have much higher chances of success I can think of far more things getting funded that are either even less likely to succeed or likely to succeed and, in so doing, will cause harm and death to many people. There are so many things we're spending so much money on that do nothing but harm it's absurd to laser focus on something you consider merely point…

Not many of those get billions of dollars, year in and year out.

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

#147

Post by Galaxeblaffer »

pfdietz wrote: post #116
Galaxeblaffer wrote: post #98

Earlier quoted context omitted.

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.

I'm not coming up with anything, but the first and glaring problem is that we can't store the energy created in any meaningful capacity. Sure we have some ideas like power2x but that doesn't really help for grid scale storage covering periods of several days where no power is created due to the weather. So imo the biggest problem is that it's just not a reliable source of energy. Here in Denmark we've spent billions on wind and we have nothing to show for it our energy is almost as dirty as when we started and the biggest reason for that is that we now use gas and biomass instead of coal. I could go on, but what it all comes down to is that we already have the perfect source of energy with nuclear fission, we can easily connect it to existing grids and it even works for district heating further decreasing our reliance on gas and fossil fuels.

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

#148

Post by pfdietz »

Galaxeblaffer wrote: post #147
pfdietz wrote: post #116

Earlier quoted context omitted.

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.

I'm not coming up with anything, but the first and glaring problem is that we can't store the energy created in any meaningful capacity. Sure we have some ideas like power2x but that doesn't really help for grid scale storage covering periods of several days where no power is created due to the weather. So imo the biggest problem is that it's just not a reliable source of energy. Here in Denmark we've spent billions…

Ok, the "can't store energy" canard.

No, we can, in multiple ways. Batteries of many different flavors, pumped hydro, storing as thermal energy (via resistive heaters or heat pump cycles), hydrogen (electrolyzers have crashed in price) and other e-fuels. Costs of these are declining rapidly as demand picks up and the scent of trillion dollar markets entices a wide range of enterprises and investors. Storage has not been much of a thing before because we were still burning fossil fuels and could just turn those up and down instead. But that doesn't mean storage wouldn't work.

In Denmark now e-fuels will be much cheaper than the fossil fuels (well, except maybe coal) you are now using. You're temporarily stuck in a rough spot right now, but the way out is via renewables + storage, and you'll be saving money doing it.

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

#149

Post by spaetzleesser »

stjohnswarts wrote: post #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?

Wendelstein 7-X is a fusion experiment. It's far away from a functioning reactor but gives a lot of input into possible designs.

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

#150

Post by jobstijl »

ncmncm wrote: post #138
jobstijl wrote: post #27

In france they are building a next privately founded stellerator which seems intresting. https://stellarator.energy/

It ought to interest securities fraud investigators, anyway. Anyone else, not so much.

Any specific reasons why you think its fraud?
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