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More invested in nuclear fusion in last 12 months than past decade

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Re: More invested in nuclear fusion in last 12 months than past decade

#621

Post by hexnuts »

acidburnNSA wrote: post #153

But where are the fusion neutrons? (See Voodoo Fusion [1]) [1] https://vixra.org/pdf/1812.0382v1.pdf I'm a professional fission guy. I started out in fusion and switched to advanced fission. These days I don't see why we don't just build lots more regular old LWR fission reactors. Imagining that somehow fusion is going to a) work, b) be cheap (fuel cost is only 5% of total nuclear fission cost so who cares), and c) n…

Honestly curious, what do you see as a solution to the heat problems reactors are experiencing? There was discussion about the combination of lack of sufficiently cool water and droughts in the new heatwave cycles.

Re: More invested in nuclear fusion in last 12 months than past decade

#622

Post by smaudet »

nl wrote: post #610
smaudet wrote: post #554

Earlier quoted context omitted.

Ok, well would you mind linking some good starting materials? And I think you maybe are more ignorant than you care to admit as well: "is that a very appreciable fraction of the energy liberated goes into radiant heat and light" https://www.atomicarchive.com/resources/documents/med/med_ch... To me that doesn't sound like "oh man the temperature in the room just went up", more like "oh man I just got a really bad sunb…

> is that a very appreciable fraction of the energy liberated goes into radiant heat and light That's exactly what I said in my previous comment: For example nuclear bombs melting flesh is because of the extreme heat, nothing that is unique to the nuclear process. You see exactly the same "flash burn" characteristics from other very hot weapons eg thermobaric explosives. The unique thing about nuclear bombs is their…

Heat is not light, that is not exactly what you said. Sorry. You didn't even mention light.

Physically as well as "mechanically", I suppose, they are very different things. Heat cannot travel at the speed of light, light can. Light can impart heat, but it is a partical-wave with various properties, heat is a general statistical statement about a set of particalls. They are not the same thing at all.

Now, as for how a sunburn works, it's not about heat. The reason you wear sunblock even on a temperate day (cold, even) but with lots of sun, is because UV light, not heat, burns your skin.

So, yeah, actually, this is different from a pure thermobaric explosive, if you want to get technical.

Now I understand you want to argue about whether "melting flesh" is unique to nuclear bombs - I never said it was. The output of a nuclear weapon, or reactor, is pretty darn unique, compared to a traditional heat thermal heat source. I don't think I ever even implied that there was some magical property of nuclear weapons which makes them "melt flesh".

You claim to be anti-nuclear yourself but you seem more interested in classifying the possible things which could be flesh melting, and/or you seem to have little to no knowledge of actual physics, thus I have extreme trouble taking you at your word.

Re: More invested in nuclear fusion in last 12 months than past decade

#623

Post by ncmncm »

bsagdiyev wrote: post #573
ncmncm wrote: post #443

Earlier quoted context omitted.

Coal and NG are, like fission, on their way out.

You argue this a lot on HN but real world shows the opposite happening.

How many coal plants are scheduled for construction, this decade?

The only place I have heard of plans to build literally any coal plants at all is in China, but they have not broken ground on them. China also says it will build hundreds of nukes, but has started only a few. It is building out solar and wind farms like nobody's business. China is always happy to cancel plans for what they turn out not to need. They even abandon things they spent big money on that turn out redundant: lately, a record-setting bridge you can read about.

We read about coal plants being shut down and scrapped, everywhere. The only place where coal plants are brought back online is in Europe in response to a regional crisis involving a war. Are you sure you want to stake claims about long-term policy based on emergency response to a war? That seems like a very courageous position to take.

Re: More invested in nuclear fusion in last 12 months than past decade

#624

Post by ncmncm »

neilwilson wrote: post #541
ncmncm wrote: post #441

Earlier quoted context omitted.

And, money is fungible . A dollar spent on X is not spent on Y. This is not a difficult concept.

It seems to be, because there isn't a fixed amount of money. Money isn't the problem. Manpower and materials are the problem. Spending manpower and materials on X cannot be spent on Y. Manpower and materials are not fungible - at least not in the nuclear space where requirements are very high.

Do you really need it explained that money represents manpower and materials?

The manpower and materials that go into nuke construction are mostly the same that go into any civil engineering construction: pouring concrete and forming steel. Concrete and steel and work on them diverted to nuke construction is unavailable for anything else.

Re: More invested in nuclear fusion in last 12 months than past decade

#625

Post by ncmncm »

thrown_22 wrote: post #528
ncmncm wrote: post #524

Earlier quoted context omitted.

To dwell on might-have-beens is to choose collapse. Fact is, to have built your nukes would have given us rashes of Chernobyls and Fukushimas, every year or two instead of every decade or two. Germany is not, in fact, building coal plants. Germany is building wind and solar farms. Until you have enough renewables to charge your storage, you burn NG at night. It would be stupid to burn NG to charge up storage, as stup…

>To dwell on might-have-beens is to choose collapse. Sounds good. Let's build nuclear reactors until we replace all energy generation with them. Dwelling on might-have-beens is to choose collapse after all.

We have the good fortune that you have no say in future plans.

Re: More invested in nuclear fusion in last 12 months than past decade

#626

Post by neilwilson »

Schroedingersat wrote: post #602
neilwilson wrote: post #544

Earlier quoted context omitted.

Solar requires land area. Storage requires land area. Britain isn't that sunny - particularly not in winter. Nuclear has a very small footprint on a crowded island. Plus we have Rolls Royce SMRs who have been building nuclear reactors for a while.

That is the admitted cost of Hinkley C and lower bound on the cost of Sizewell (it will go up, they always do). Sizewell is a rolls royce smr. Matching end user retail cost of solar. Right now. By the time sizewell comes online it'll be a fraction. It's also calculated with a 12.5% capacity factor which is winter in the UK. Add in overnight costs and it's extremely one sided. You could add as much net capacity as the…

"If there are trillions in the pot"

There are always trillions in the pot, because the UK is a sovereign country with its own currency. Money is never the issue.

Therefore it's only overnight costs that matter in a build (and hitting the deadline). The real issue is one of manpower and stuff. We don't make solar panels in the UK. We will make SMRs. Therefore we're not reliant on Chinese manufacture, or the whims of export markets to fund them. A problem we're currently having with gas and oil.

To have security of energy supply over time you have to be as decoupled from world markets as possible. We don't want to be in the situation where we're relying on China for replacement advanced manufactures to keep the lights on.

Solar has no reliable capacity in winter in the UK unfortunately. You wouldn't want to rely on solar with several weeks of grey miserable UK winter weather even with storage. The same with wind, which is still suffering from a degradation in capacity due to the as yet unexplained overall reduction in wind speeds - which may itself be a result of climate change.

Re: More invested in nuclear fusion in last 12 months than past decade

#627

Post by acidburnNSA »

hexnuts wrote: post #621
acidburnNSA wrote: post #153

But where are the fusion neutrons? (See Voodoo Fusion [1]) [1] https://vixra.org/pdf/1812.0382v1.pdf I'm a professional fission guy. I started out in fusion and switched to advanced fission. These days I don't see why we don't just build lots more regular old LWR fission reactors. Imagining that somehow fusion is going to a) work, b) be cheap (fuel cost is only 5% of total nuclear fission cost so who cares), and c) n…

Honestly curious, what do you see as a solution to the heat problems reactors are experiencing? There was discussion about the combination of lack of sufficiently cool water and droughts in the new heatwave cycles.

Most of those problems are related to fish populations and their tolerance of warm water. I think we will probably need to either adjust the regulations and/or somehow keep the fish farther away from the discharge so that they don't get injured.

Cooling a 375°C core with ambient water can be done even well into climate change conditions.

As for drought, if reactors are cooled by rivers that can dry up rather than oceans or large lakes, then they'll have to consider switching to dry cooling, which is less efficient but works with almost zero water usage. This would work better with higher temperature reactors than typical water cooled ones.

I also am a huge proponent of using reactors district heating and cooling, so we can put that warm water to good decarbonized uses.

Re: More invested in nuclear fusion in last 12 months than past decade

#628

Post by dmitriid »

pfdietz wrote: post #594
dmitriid wrote: post #522

Earlier quoted context omitted.

> Is there any progress in design of nuclear fission power plants regarding safety? > Fukushima... You mean, hit by the most powerful earthquake recorded in Japan, flooded by a tsunami with 13-14 meter-high waves, evacuated, failed to shutdown, had three core meltdowns and several explosions, and resulted in... 1 death from radiation, 2000 deaths from evacuation and 45 radiation-resulted injuries. I'd say even this o…

> 1 death from radiation So far. The population dose will likely cause many more fatal cancers than that (maybe 200?). That those will be impossible to detect above the normal cancer background doesn't mean we can pretend they aren't there.

So, after a full-scale catastrophe it's still significantly fewer casualties than from normal operation of coal, for example.

Re: More invested in nuclear fusion in last 12 months than past decade

#630

Post by manholio »

pfdietz wrote: post #513
manholio wrote: post #189

You could say the same thing about Bitcoin. Fusion is in the VC hype cycle but there are no new developments that suggest it can become cheaper and more predictable than fission, which itself is dying, primarily because of financial uncertainties and risks. On the contrary, physics suggest that performance scales with size, so even the extraordinary expensive ITER project is way too small to achieve engineering break…

Fusion reactors (after they're big enough to have ignited) have diseconomy of scale, due to the square-cube law. Cost scales (at least) as reactor volume, while power is limited by power/area through the surface of the reactor vessel.

But are we hitting that power density ceiling yet? It doesn't seem so, we're not even in the "big enough to have ignited" range, only scraping at the door of "big enough for scientific break-even", but have already blown any reasonable chance for such designs to be cost effective even if they were to be mass produced.

Massive superconducting magnets generating megatons of force, building-sized vacuum chambers that are almost guaranteed to leak some amount tritium, which only adds to the unavoidable regulatory burden imposed by the fast neutron environment, activated structure and every day production of weapon-grade material etc. etc., even if the current technology magically works tomorrow, it's still an economic dead-end.

The present fusion crop is megascience at its worst, draining public funds for something that can't possibly ever work and producing very little substantial science in the way. We need to take a step back and reassess. At least Helion is trying a new path, even if they are likely to end up in a similar dead-end.

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