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Nuclear-fusion reactor doubles record for energy made from fusing atoms

nature.com

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Re: Nuclear-fusion reactor doubles record for energy made from fusing atoms

#231

Post by lambdatronics »

Aeolun wrote: post #17

As much as I enjoy reading this news. It is feels heavily sensationalized. "Smashes" the energy record. We're talking about a fusion generator here, that after 25 years of work, now manages to output 'double' the energy, to 59 MJ in 5s -like 20 MW- while requiring 180 MJ input power. Somewhere hidden in the article is the news that this could mean a input/output ratio of 10 in a full scale reactor, but that's also so…

Fusion researcher here. Yes, this piece is sensationalized, as are most pieces about fusion, and about science/technology in general, unfortunately. It's depressing that tokamak performance hasn't improved much in all that time. The only two ways to scale up the gain are to build the device larger (like ITER) or with higher magnetic field (like SPARC). The existing devices have been around for many years and have been pushed basically as far as they can go, the only way forward is to build new devices. There's really no reason to expect a breakthrough on tokamak performance that will suddenly change the game. The only really positive news for tokamaks in the last ~30 years is the advent of REBCO superconductors & the success Commonwealth Fusion has had so far in capitalizing on this technology.

Re: Nuclear-fusion reactor doubles record for energy made from fusing atoms

#232

Post by DennisP »

Retric wrote: post #137
DennisP wrote: post #133

Earlier quoted context omitted.

Those interconnects take a long time to build, mostly due to political opposition, and aren't that cheap either. For example, the 2GW 400-mile Southern Cross has turned out to be a 17-year project, costing $2 billion. https://www.eenews.net/articles/what-a-2b-texas-project-says... They're not the only ones: > the 732-mile TransWest Express high voltage transmission line filed its first permit application in 2007, but…

That’s a solid point, but it only needs 3-4 years to build. “$2 billion project, proposed by Pattern Energy Group LP, likely won’t be ready until 2026 at the earliest, if construction starts in 2023.” Nuclear also takes 4-6 years to build but can take decades to get permission to start.

Of course. I used "complete" in a later sentence, which is really what I meant, and why I talked about political opposition being the main issue.

Re: Nuclear-fusion reactor doubles record for energy made from fusing atoms

#233

Post by ncmncm »

RandallBrown wrote: post #213
wanda wrote: post #197

Earlier quoted context omitted.

Sadly, the notion of "free energy" in a capitalist context is probably why the concept hasn't taken off.

If you can generate the energy for "free" then you can sell it for cheap and undercut every other producer. It seems to me that it works very well in a capitalist context.

That is, indeed, the solar power value proposition. Nukes, not so much: the operating cost is very high.

Re: Nuclear-fusion reactor doubles record for energy made from fusing atoms

#234

Post by ncmncm »

nightgarden wrote: post #87
panick21_ wrote: post #78

Fusion has no practice reason to exist compare to advanced fission. The improvements in energy density are not really relevant factor at that scale, meaning the difference from oil to fission, and oil to fusion doesn't really gain you much. Fusion fuel cost over the long term is likely more expensive then a fission fast breeder (not to mention a potential of thorium thermal breeder). Is a fusion reactor going to be c…

Isn't fusion safer? If fusion was a viable option for countries that are phasing out fission like Germany then it could solve a lot of problems especially decreasing reliance on gas

Thousands of tons of radioactive molten lithium would be quite noticeable if spilled, especially since it would instantly burst into flame, and spraying water on that would make it explode.

On the plus side, it wouldn't be very radioactive, not like a nuke meltdown. Mostly molten and on fire.

Re: Nuclear-fusion reactor doubles record for energy made from fusing atoms

#235

Post by [deleted] »

Loughla wrote: post #176
pontifier wrote: post #159

Earlier quoted context omitted.

It's an easy article to write, and it's easy because so many others have written the same thing. It's like articles about Facebook and how their value fluctuates and this or that privacy issue is going to be fixed soon. People have heard about the big players, so big players get the attention. I'm trying to do some fusion research myself, but it's extremely difficult to get anyone to take what I'm doing seriously. I'…

You have a 48 second youtube simulation video, and one paragraph explaining nothing. How is this supposed to help people take you seriously? What are your credentials? Why should anyone take you seriously? Are you an academic? Have you submitted this to academic journals or individuals? Have you tried to make or made any connections to anyone in the field? Also, are you the guy who bought the warehouse full of CD's?

[deleted]

Re: Nuclear-fusion reactor doubles record for energy made from fusing atoms

#236

Post by ncmncm »

pontifier wrote: post #215
hoelle wrote: post #163

Earlier quoted context omitted.

Recommendations include: 1) ditching the toxic negative attitude. It pushes away interest. 2) spend an afternoon or a few bucks on a web designer making your site look better than the "time cube" site. It practically screams crackpot theory. 3) build credibility with academics first. People not in the field will assume you're a swindler by default.

1 - I agree, I've been fighting too many battles on too many fronts and my optimism has been taking a hit. 2 - I see, I'll look into presenting more professionally. 3 - I believe Ideas should be evaluated on their merit, and what people think about the idea or myself isn't going to change the physics. It will either work or it won't

3 - It could work, but badly. That is what they are shooting for at ITER.

Re: Nuclear-fusion reactor doubles record for energy made from fusing atoms

#237

Post by ncmncm »

marcosdumay wrote: post #132
ncmncm wrote: post #62

Earlier quoted context omitted.

The energy flux density in the most compressed plasma imaginable is orders of magnitude less than in fissile uranium. So, to match power out, it has to be big. Really, really big. And a fusion reaction chamber is a much more expensive affair than a fission pile: super high-tech materials and construction, enormous magnets (blasted by the hot-neutron flux output), piping for thousands of tons of melted lithium that ha…

> So, to match power out, it has to be big. Really, really big. Fusion has all of the characteristics of something you'll want to do if you are in space. Add to that the fact that its fuel is much easier to acquire than fission and that solar isn't available everywhere and you have a winner. Meanwhile down to Earth, yes, most likely it will never be an important energy source.

For use in space, you need a reactor whose energy does not come out as hot neutrons. Even gamma rays would be better.

D-He3 (deuterium and synthetic helium) is attractive, except you have to make the He3 by making tritium and waiting for it to decay. pB (hydrogen and boron) is attractive, but much harder to make work than D-He3.

There is work on a D-He3 rocket, tagged "Princeton FRC", that they hope to loft for a trial maybe in 2035. Elon could get it tried out earlier, and ought to. We should be cranking tritium production up immediately so there will be enough He3 when we need that.

Re: Nuclear-fusion reactor doubles record for energy made from fusing atoms

#238

Post by ncmncm »

Paradigma11 wrote: post #139
marcosdumay wrote: post #132

Earlier quoted context omitted.

> So, to match power out, it has to be big. Really, really big. Fusion has all of the characteristics of something you'll want to do if you are in space. Add to that the fact that its fuel is much easier to acquire than fission and that solar isn't available everywhere and you have a winner. Meanwhile down to Earth, yes, most likely it will never be an important energy source.

But you dont need a lot of fuel for fission and you also need many other things to keep a ship/station running. Isnt fuel in the ballpark of just one of many consumables that you need?

Fission-powered ion propulsion is the best mature tech we have.

In space, the fission doesn't need containment, or even much shielding if it is far enough away from the rest of the ship.

In the cloud tops of Titan, Venus, Saturn, Uranus, or Neptune, a nuclear power plant may be as simple as a naked pile suspended near the bottom of a big fabric tube with wind turbines at the top. The radioactively-heated, buoyant air inside holds it up, and, escaping through the turbine, generates power. (Enough is held back so it stays up.)

Perhaps surprisingly, gravity is almost Earth-normal on all four planets. Perhaps more surprisingly, the temperature at a not unreasonably-high pressure is also close to Earth-normal (except on Titan). But getting back to orbit from any of the last three would be very, very difficult, so such a reactor would only ever power robots.

Getting back to orbit from Titan is easy. From Venus, it is pretty hard; and once in orbit you would need to refuel to get anywhere else.

Re: Nuclear-fusion reactor doubles record for energy made from fusing atoms

#239

Post by pfdietz »

dahfizz wrote: post #225
zardo wrote: post #220

Earlier quoted context omitted.

That sounds like a proposal for just not de-carbonizing until fusion is ready. Is that what you mean? When do you think we could have say 5% of the worlds power coming from fusion reactors?

I'm happy to increase renewable energy production where possible. My point is that saying "we can just be 100% solar" is just as impractical and far fetched as saying "we can just be 100% fusion". Renewable advocates would be more successful if they were realistic about the problems with significant solar reliance.

I disagree. 100% solar is much less far-fetched than 100% fusion, because the latter is a much larger technological and economic stretch.

Re: Nuclear-fusion reactor doubles record for energy made from fusing atoms

#240

Post by orthecreedence »

ncmncm wrote: post #230
orthecreedence wrote: post #199

Earlier quoted context omitted.

> They have clear political motivation to continue to build nuclear power plants. If realizing what a terrible bet solar and wind are is political, then yes I agree their motivation is political.

Strange, then, that they are building more solar and wind than fission.

Why not build both? Nuclear is great, and pound-for-pound is a much better energy source than solar, but you can build solar much more quickly than nuclear. I don't think your rebuttal is particularly damning.

My points against solar I raised to you in another thread stand: to build the panels/batteries we need, it will create an extreme excess of carbon in the atmosphere. That's not to say we shouldn't build solar, but to pretend it can solely serve all of our collective energy needs is myopic give the constraints.

To be clear, I'm all for covering the entire planet in solar panels...after we switch our production to be powered via fission.

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