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Compact nuclear fusion reactor is 'very likely to work,' studies suggest

nytimes.com

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Re: Compact nuclear fusion reactor is 'very likely to work,' studies suggest

#311

Post by mantap »

Baeocystin wrote: post #238
beervirus wrote: post #136

Earlier quoted context omitted.

There's something that feels so archaic about using a nuclear reactor to... boil water and spin a turbine. It's disappointing that we haven't figured out a better way to convert to electrical energy than what we were using in the 1800s.

Water is an amazingly capable working fluid. Just because it's ubiquitous doesn't mean it doesn't have remarkable properties!

In fact, the fact it's ubiquitous is no coincidence and can be explained by the anthropic principle. The human body is a chemical machine too.

Re: Compact nuclear fusion reactor is 'very likely to work,' studies suggest

#312

Post by alex_young »

Deestan wrote: post #258
alex_young wrote: post #246

Let’s say this works. What do you do with all the neutrinos? How do you deal with all of the radioactive waste from the containment equipment?

Neutrinos: https://what-if.xkcd.com/73/ Waste: https://www.iaea.org/topics/energy/fusion/faqs

From your IAEA link:

“ The activation of the reactor’s structural material by intense neutron fluxes is another issue. This strongly depends on what solution for blanket and other structures has been adopted, and its reduction is an important challenge for future fusion experiments.”

Re: Compact nuclear fusion reactor is 'very likely to work,' studies suggest

#313

Post by de_watcher »

Stubb wrote: post #87
Florin_Andrei wrote: post #54

Earlier quoted context omitted.

Make an efficient fusion reactor the size of a truck, and the solar system becomes your backyard.

Make an efficient fusion reactor of any size, and you can power Fischer-Tropsch plants to synthesize carbon-neutral hydrocarbon fuel for the existing fossil-fuel infrastructure.

Screw that. Fossil-fuel infrastructure is smelly and noisy. That's my first concern, I don't even need to "care about the planet" to hate fossil fuel.

Re: Compact nuclear fusion reactor is 'very likely to work,' studies suggest

#314

Post by el_oni »

taneq wrote: post #219
samatman wrote: post #167

Earlier quoted context omitted.

It's a good contribution to the conversation, keeping in mind that Adm. Rickover wrote these words in 1953. Anyone could have said similar things about computers in 1953, and been just as correct. Are nuclear reactors computers? Of course not, and neither have practical reactors kept pace in development with practical computers. But neither is it inevitable that steady progress cannot grind down the latter set of cha…

Ah, back in 1953, when they were only 20 years away from practical nuclear fusion.

As opposed to 2020 where we're now only about 20 years away from practical nuclear fusion

Re: Compact nuclear fusion reactor is 'very likely to work,' studies suggest

#315

Post by MagnumOpus »

Retric wrote: post #178
ClumsyPilot wrote: post #173

Earlier quoted context omitted.

Thats not accurate at all, Uranium itself is much cheaper than coal / any fuel per unit energy. Some contries have permanent, final storage for nuclear waste, it does not cost any more once created. Furthermore, not only was solar power borderline non existent when those reactors were built, it is also still intermittent. You are just glossing over the biggest challenge of energy - balancing the powe grid. No-one nee…

Nuclear has the opposite problem as solar in that it needs high uptime 24/7 to stay reasonably economical. You can easily design a grid following reactor as seen with nuclear subs etc, it just doesn’t save you any money. 24/7 365 grid scale battery backed and thus load following solar runs about 8c/kWh* which is cheaper than nuclear at high utilization. Sure, France’s model of importing and exporting significant chun…

Excluding the most northern areas is a pretty big issue. Most of Europe is north of 45 degrees north... Yes, Hawai'i and California can be supplied with solar panels cheaply; the UK can't.

Re: Compact nuclear fusion reactor is 'very likely to work,' studies suggest

#316

Post by MagnumOpus »

Retric wrote: post #286
ClumsyPilot wrote: post #183

Earlier quoted context omitted.

I am really tired of this line - the taunami killed 18,500 people. The reactor incident killed no-one through radiation and 32 people through physical injuries. One failure of Banqiao Dam killed an estimated 240,000 people. That's more than all people who have ever died from anything to do with nuclear, reactors and bombs combined. Air pollution kills about 2,000 people every single day. Reactor incidents are like pl…

Killing people is hardly the only issue. Rendering large tracts of land uninhabitable is extremely expensive. All told 4 nuclear reactors have had major issues, 2 subs and 1 power plant run by the USSR, and then another one very recently by Japan. Plus several near misses. That’s a significant percentage of total reactors ever built including what was considered a safe design. We could go 1000 years without another i…

> Rendering large tracts of land uninhabitable is extremely expensive

Have you ever been near a coal ash pond? You probably haven't because it is an extreme health hazard to get anywhere near it, as it is full of mercury, arsenic, heavy metals and occasionally radioactive slurry.

There about a thousand of these ponds in the US alone totaling maybe 100,000 acres. Meanwhile all the nuclear power plant waste ever produced could fit into a single large hangar...

Re: Compact nuclear fusion reactor is 'very likely to work,' studies suggest

#317

Post by rurp »

andi999 wrote: post #232
rurp wrote: post #131

Earlier quoted context omitted.

Do you think that a better approach, given a lot of resources, would be to push more general/fundamental research without a clear end goal in mind? That approach makes sense to me intuitively given how many surprising breakthroughs there have been throughout history, but I admittedly know very little about actual research.

Most surprising breakthroughs (am not a historian though) were found with a clear goal in mind. It was just that the goal was very different from the breakthrough.

Ah ok, thanks. I guess in that case a good strategy could be to pursue a lot of specific goals, even if they don't seem worth it on the face of it. Seems like an approach the Ig Nobel awards would appreciate.

Re: Compact nuclear fusion reactor is 'very likely to work,' studies suggest

#318

Post by MertsA »

dbetteridge wrote: post #274
Robotbeat wrote: post #204

Earlier quoted context omitted.

I think they're using Yttrium (i.e. YBCO), right? It's hard to find that info.

https://nationalmaglab.org/magnet-development/magnet-science... Looks like they 'only' need to be at 4.2Kelvin as well to operate, which is a definite improvement

They don't need to be that cold to start superconducting, 4.2K is just the temperature you could expect with liquid helium cooling. It would actually be superconducting with liquid nitrogen but the reason why you would still want to go colder is because superconductors have a maximum magnetic flux that they can sustain while still being superconducting. The current travelling through a superconductor itself also contributes to the magnetic flux so even though it's superconducting there's still a limit as to how much current you can pass through a conductor and how high of a magnetic field you can create. This limit is dependent on temperature though, so you definitely want to use liquid helium so you can create a much stronger magnetic field.

Re: Compact nuclear fusion reactor is 'very likely to work,' studies suggest

#319

Post by princekolt »

bad_alloc wrote: post #2

> If we can overcome the engineering challenges, this machine will perform as we predict If?

"Engineering challenges" means they already know the practical solutions, they just need to figure out how manufacture and assemble them.

Re: Compact nuclear fusion reactor is 'very likely to work,' studies suggest

#320

Post by Retric »

MagnumOpus wrote: post #315
Retric wrote: post #178

Earlier quoted context omitted.

Nuclear has the opposite problem as solar in that it needs high uptime 24/7 to stay reasonably economical. You can easily design a grid following reactor as seen with nuclear subs etc, it just doesn’t save you any money. 24/7 365 grid scale battery backed and thus load following solar runs about 8c/kWh* which is cheaper than nuclear at high utilization. Sure, France’s model of importing and exporting significant chun…

Excluding the most northern areas is a pretty big issue. Most of Europe is north of 45 degrees north... Yes, Hawai'i and California can be supplied with solar panels cheaply; the UK can't.

Can’t is really just a cost question. 8.2 percent of Germany‘a gross-electricity generation comes from PV solar and their southernmost point is 47°17'N. IMO, that was an over investment, but that’s their choice. Most people in Canada live south of that so we are not talking about that many people.

We are really talking about a handful of countries. The Nordic countries have cheap alternatives in hydroelectric, wind and geothermal energy. Nuclear may have a few niche applications for northern islands etc, but that’s not really significant globally.

PS: 4% of the UK’s electricity comes from solar and their southern tip is a actually quite decent for solar.

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