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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

#331

Post by outworlder »

drran wrote: post #256
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…

Tsunami and earthquakes are not man generated events, so we can dismiss them. Yes, they killed a lot of people, but cancer kills even more: about 10 millions per year. In part, cancer is caused by contamination of food by radionuclides from reactor leaks (Chornobyl) and nuclear bomb testing.

> In part, cancer is caused by contamination of food by radionuclides from reactor leaks (Chornobyl)

Sorry, this is just misinformation. Residual radiation worldwide from nuclear testing or Chernobyl is minuscule. We wouldn't even be able to detect anything if we didn't have incredibly sensitive instruments.

The sun is a much larger daily source of radiation. Or a banana.

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

#332

Post by outworlder »

m0zg wrote: post #249
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…

I'm really tired of this line as well. Had they failed to contain Chernobyl, much of Eastern Europe would be contaminated for thousands of years. It is true that today's reactor designs are much safer than RBMK, but I will prefer the reactor can can't go supercritical to one that can any day, especially if it's nearby.

> but I will prefer the reactor can can't go supercritical to one that can any day, especially if it's nearby.

Newer design's can't go supercritical.

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

#333

Post by outworlder »

alexpotato wrote: post #35
rsynnott wrote: post #27

Earlier quoted context omitted.

The actual fusion in the sun happens in only a small part At the middle. The rest is just there to provide mass :) > Also, something else I never grokked, how do you get the power out? The plasma heats up, but how do you turn that into useful electrical energy? Steam turbines; same as fission or coal. Or gas turbines, if you want to get fancy.

There is a science fiction story by, I believe, Isaac Asimov which has as it's main story point that: - fusion is developed - b/c of fusion, the cheapest "rocket fuel" is basically water heated into steam by the fusion reactor - people on Earth get upset about the "spacers" taking all of the "earthers" water - the spacers then have to go to other sources of water in the solar system (I think it was either rings of Sa…

> without the extra step of breaking H2O into hydrogen and oxygen

Heat it sufficiently and it will be broken down.

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

#334

Post by o-o- »

A couple of reflections. The first one being that fusion might very well be the remedy to get rid of carbon emissions once and for all, however it won't affect global warming. In fact, it might make it even worse.

The simple line of reasoning being that if energy becomes 100 times cheaper, humanity will fast find ways to consume 100 times the amount of energy. A high amount of that energy will end up as heat.

The second reason... and you'll find it apparent I'm not a physicist, but reading about fusion research always has me worried. We're basically talking about starting a "controlled" chain reaction at millions of degrees, "like the one on the sun". The sun isn't a nice place, and the sun's fusion happens to be controlled just because it's surrounded by lightyears of vacuum.

-Yeah but we'll have magnetic fields and super coils and stuff. It's totally safe. -Totally safe? -Yes, our calculations say its totally safe. -Your calculations based on current theory? Guess what, theory is a moving target. Just a few years ago you didn't even know if the Higgs particle exists?

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

#335

Post by DennisP »

galangalalgol wrote: post #310
DennisP wrote: post #289

Earlier quoted context omitted.

We have plenty of lithium. All D-T fusion designs breed tritium from lithium, using the high-energy neutrons from the reaction.

I assume very little lithium is actually needed, will the dramatically increased demand from battery manufacturing affect feasibility?

Lithium production is a bit strained but lithium resources are fairly high. At Tesla's Battery Day they said just the lithium in Nevada is enough to electrify the entire US fleet. They also plan to do their own recycling, which they expect to work well since they can customize it to their battery.

Given the amount of energy that comes from fusion fuel, even extracting lithium from seawater would probably be economical.

Beryllium is much less common so that could be an issue. But maybe we can find more beryllium if we look harder; right now we barely use it. If we can't find enough, we could probably design a reactor to use lead instead. Either one acts as a neutron multiplier, and General Fusion's design uses lead instead of beryllium, for the same purpose.

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

#336

Post by drran »

outworlder wrote: post #331
drran wrote: post #256

Earlier quoted context omitted.

Tsunami and earthquakes are not man generated events, so we can dismiss them. Yes, they killed a lot of people, but cancer kills even more: about 10 millions per year. In part, cancer is caused by contamination of food by radionuclides from reactor leaks (Chornobyl) and nuclear bomb testing.

> In part, cancer is caused by contamination of food by radionuclides from reactor leaks (Chornobyl) Sorry, this is just misinformation. Residual radiation worldwide from nuclear testing or Chernobyl is minuscule. We wouldn't even be able to detect anything if we didn't have incredibly sensitive instruments. The sun is a much larger daily source of radiation. Or a banana.

Radiation from Chornobyl affected large area, but not whole world. People die from radiation induced cancer in affected areas only, of course.

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

#337

Post by rrrrrrrrrrrryan »

IBCNU wrote: post #142
ElFitz wrote: post #137

Earlier quoted context omitted.

> this is still exciting given how anemic advancement in the fusion space has been for 50+ years. "Nuclear fusion. 30 years away since 1950" Joking aside. I too am glad to see some progress of any kind, and new (seemingly credible) initiatives being funded and pursued

`"Nuclear fusion. 30 years away since 1950"` I feel like there should be bonus points for getting this quote to the top of every fusion article posted until there's an existing fusion reactor.

Relevant xkcd: https://m.xkcd.com/678/

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

#338

Post by drran »

FriskyAlter wrote: post #294
drran wrote: post #256

Earlier quoted context omitted.

Tsunami and earthquakes are not man generated events, so we can dismiss them. Yes, they killed a lot of people, but cancer kills even more: about 10 millions per year. In part, cancer is caused by contamination of food by radionuclides from reactor leaks (Chornobyl) and nuclear bomb testing.

Yes, cancer did not exist before nuclear. We can blame cancer on nuclear plants and bombs. That's quality commentary.

Radionuclides are major contribution to growth of cancer rate.

Quote: Radioactive fallout from nuclear weapons tests probably caused 17,000 cancer deaths in the United States in the latter half of the 20th century

http://news.bbc.co.uk/2/hi/americas/1849471.stm

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

#339

Post by blamestross »

o-o- wrote: post #334

A couple of reflections. The first one being that fusion might very well be the remedy to get rid of carbon emissions once and for all, however it won't affect global warming. In fact, it might make it even worse. The simple line of reasoning being that if energy becomes 100 times cheaper, humanity will fast find ways to consume 100 times the amount of energy. A high amount of that energy will end up as heat. The sec…

Just to give a little insight, the "containment" isn't about safety, it is about squeezing everything together. It goes away, so does the reaction. It fizzles, it doesn't blow up. The fusion in the sun is essentially gravity+mass applying so much pressure that stuff fuses. Fusion hypothetically is by far the safest means of getting power we will ever work out.

Global warming isn't about heat generation. The sun (the free fusions reactor in the sky) sends more heat our way then we could ever hope to produce. It is heat dissipation that is the problem. Greenhouse gasses prevent the sun's heat from dissipating. This is the problem, we will only make it better by stopping greenhouse gas emissions.

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

#340

Post by drran »

joncrane wrote: post #325
drran wrote: post #256

Earlier quoted context omitted.

Tsunami and earthquakes are not man generated events, so we can dismiss them. Yes, they killed a lot of people, but cancer kills even more: about 10 millions per year. In part, cancer is caused by contamination of food by radionuclides from reactor leaks (Chornobyl) and nuclear bomb testing.

I believe that coal releases more radioactivity into the environment than nuclear energy.

Quote:

McBride and his co-authors estimated that individuals living near coal-fired installations are exposed to a maximum of 1.9 millirems of fly ash radiation yearly. To put these numbers in perspective, the average person encounters 360 millirems of annual "background radiation" from natural and man-made sources, including substances in Earth's crust, cosmic rays, residue from nuclear tests and smoke detectors.

https://www.scientificamerican.com/article/coal-ash-is-more-...

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