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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

#251

Post by joak »

sva_ wrote: post #109

Something I wondered about fusion is, where does all that 'excess energy' go? I mean don't understand me wrong, it is obvious that is a much better form of energy release than all the other forms of energy production we have; but let us consider we manage to gain energy from fusion, the electricity released still releases heat, so how does it dissipate, if we have near-infitite energy, and anyone can spend as much as…

The total amount of waste heat is low. Thermal pollution is a local problem (rivers getting hot) but not a global issue.

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

#252

Post by lambdaba »

slothtrop wrote: post #234
lambdaba wrote: post #190

Earlier quoted context omitted.

So the fear is we’ll use the extra energy to literally warm the planet? Seems like a scale mismatch. Climate “engineering” like blocking out the sun seems like a much more real danger

Not "warm", because with fusion filling this cache, energy usage wouldn't lead to CO2 pollution. They're suggesting it would lead to increases in consumption which means waste. Notwithstanding that a) life won't necessarily get more affordable for people, and stuff costs money, b) there are innovations now, and expected in the future, which would drastically curtail waste, though some regulatory measures might be nec…

I don't see why it goes without saying the extra energy would necessarily go towards consumerism. There is still a long way to go towards getting every human a decent life and opportunity to reach their full potential. There's no way we're getting there without the extra energy. For providing healthcare, nutricious food, education, etc.

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

#253

Post by downrightmike »

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…

The problem is energy companies and the entrenched family assholes that run them. Three Mile Island was being forced to push ahead and use the crane to move the vessel, even though it WAS damaged and would have likely lead to a meltdown. Engineers knew it wasn't safe and were punished and fired for not using the crane unless it was actually checked and in working order. The public is right to be wary of nuclear when these are the types of assholes that put all our lives in danger.

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

#254

Post by indymike »

jmyeet wrote: post #200
acidburnNSA wrote: post #169

Earlier quoted context omitted.

Groan here we go again. > Oh, yeah, just fine, not a hitch: Now show me list of the 8 million people who die per year from air pollution. https://www.who.int/health-topics/air-pollution > The solution being: Ignore it, I guess? I mentioned the solutions but didn't provide a link. here you go. https://www.posiva.fi/en/index.html > And we fight wars for peace too. See the literature https://pubs.giss.nasa.gov/abs/kh050…

> Groan here we go again. Yeah, we do with more pro-nuclear propaganda and outright falsehoods (again). > Now show me list of the 8 million people who die per year from air pollution. No, it doesn't. Here's the exact quote from your source: > The combined effects of ambient air pollution and household air pollution is associated with 7 million premature deaths annually. Not "die from" but "is associated with". What d…

> I swear nuclear fan boys are just as delusional as climate deniers.

No, some of us actually have operated a reactor for a living, and have first hand experience with the technology, and most of the issues people like to discuss. In my case, I served in the US Navy in nuclear propulsion. This whole debate seems crazy. Truth is the tech works, and it should be inexpensive compared to burning fossil fuels. Then there is the absolutely incredible difference in energy density - a two 13mmx13mm fuel pellets contains roughly the same energy as 1 ton of coal, or 260 gallons of oil. As far as renewables go, it has to be much worse for the world to build the 1650 wind turbines, wire them, and so on that it takes to match a typical single civilian reactor. To those of us who have worked with the technology, we know it could really change the world's carbon problem.

The reason the cost is so high - and remember, the cost of technology usually goes down over time in a normal functioning market, is hyper-regulation at every level of government. From mining and refining fuel to building plants to operating them, there is an insane amount of regulation and litigation over that regulation. The over-regulation argument is really annoying, mostly because it is true.

It's also true that there are some issues around dealing with waste. Most of these are easily solved, but will not be for the same over-regulation reasons. We've taken perfectly good tech and through the power of bureaucracy, made it unworkable.

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

#255

Post by pfdietz »

acidburnNSA wrote: post #238
pfdietz wrote: post #232

Earlier quoted context omitted.

If you fully fission the U + Th in an average chunk of crustal rock (using breeding so you can use the 238U and 232Th) then said rock releases fission energy equal to the combustion energy of 20x its mass in coal. So with breeders we can in effect treat the entire Earth's crust as something an order of magnitude more energy rich than coal. (Whether breeders are practical or competitive is another matter, but then fus…

This shocking factlet is repeated, verified, and credited to you in the writeup in my sibling comment.

So you did, thanks! BTW, the Earth becomes uninhabitable in about 1 billion years, not 4.

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

#256

Post by seventytwo »

tejohnso wrote: post #225
acidburnNSA wrote: post #197

Earlier quoted context omitted.

Uranium and thorium fuel on earth can make 100% of today's primary energy for about 4 billion years, using breeder reactors, which were proven in 1952 near Arco Idaho at the Experimental Breeder Reactor 1. Writeup explaining this with lots of actual scientific references at the bottom here: https://whatisnuclear.com/blog/2020-10-28-nuclear-energy-is-... People who say uranium will last 50 years either aren't aware of…

This is so depressing. It's nearly impossible to form a confident opinion these days without a ton of effort. I heard Sabine, I said to myself...makes sense...and it looks like she's put a lot of work into understanding all of this, and she is a professional. So that was it. Now you're saying she's wrong. Very wrong. And you're a nuclear reactor physicist (thanks for comment!) Am I going to go read all of the relevan…

It’s always been this way, and it will always be this way.

Don’t get discouraged. This is all part of the process of finding and disseminating knowledge.

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

#257

Post by pfdietz »

DennisP wrote: post #240
sweezyjeezy wrote: post #211

Earlier quoted context omitted.

Also hand waving away the fact that the waste products have to be managed for civilisation-length time scales.

Only if we never use fast reactors, which fission almost all the long-lived stuff. Take what's left, encase it in glass and bury it, and it'll be back to the radioactivity of the original ore in 300 years.

Well, except for the 7 long lived fission products. Those are possibly good targets for space disposal.

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

#258

Post by pyuser583 »

acidburnNSA wrote: post #197
spawarotti wrote: post #194

Earlier quoted context omitted.

How long will the fuel last? Sabine Hossenfelder references studies in which we have enough Uranium for 50 years max. 6:08 here: https://youtu.be/0kahih8RT1k

Uranium and thorium fuel on earth can make 100% of today's primary energy for about 4 billion years, using breeder reactors, which were proven in 1952 near Arco Idaho at the Experimental Breeder Reactor 1. Writeup explaining this with lots of actual scientific references at the bottom here: https://whatisnuclear.com/blog/2020-10-28-nuclear-energy-is-... People who say uranium will last 50 years either aren't aware of…

Everything I know about breeder reactors comes from the Radioactive Boyscout, which says they sounds great but are insanely unstable and not yet workable.

Is that true? What’s the state of breeder reactors today?

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

#259

Post by godelski »

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, I don't understand why we can't do both. I don't think this has to be framed as a zero sum problem (I think way too many issues are naively framed that way). With reference to the article, the funding levels over the past decade (globally) were roughly $200m/yr. That's really nothing in terms of government money and well within the realm that just the US could sustain such an effort alone. It would be roughly 0.004% of our yearly budget! That's an insanely low amount of money to spend given the potential upsides. You're right that there's weapons proliferation problems with both, but honestly that also seems like a good argument for pulling that funding out of what is already allocated to military budgets (not trying to defend nuclear weapons here, but we do have to acknowledge the existence of the military industrial complex and that they dictate a lot of the US budget).

> Anyway let's ~~just~~ do fission you guys.

So I agree with you. Let's do fission, but not _just_ fission. Let's put a lot of money into it and bring down the costs. The cost of climate change clearly far outweighs the cost of nuclear plants and waste. And that the waste really isn't a problem, as you yourself have extensively written about. These arguments always go "nuclear vs x" and honestly I want to see "fission + fusion + solar + wind + hydro + batteries." I don't see why we can't have it all. The zero sum arguments seem to make such a dream more difficult to achieve.

Also, good to see you back. Always glad to see your input on these posts.

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

#260

Post by joak »

pfdietz wrote: post #250
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…

> I started out in fusion and switched to advanced fission. You are in good company. Lawrence Lidsky, the fusion guy at MIT who wrote the famous article "The Trouble with Fusion" back in the 1980s, also switched to advanced fission reactors. His critique of DT fusion is still worth reading. The big issue, the lousy volumetric power density of DT fusion reactors compared to fission reactors, is still a huge albatross…

And what about non-DT fusion?

Helion, funded by Sam Altman, is doing DD/DHe3 fusion. Non-thermal fusion with direct energy conversion. They are attempting net electricity for 2024.

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