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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

#241

Post by Igelau »

Tossrock wrote: post #150

I wish these people the best, and I really hope they get a working fusion plant soon. That said, I can't resist sharing Admiral Rickover on academic reactors vs practical reactors: Important decisions about the future development of atomic power must frequently be made by people who do not necessarily have an intimate knowledge of the technical aspects of reactors. These people are, nonetheless, interested in what a…

I hear Adm. Rickover fixed a whole toothpaste factory once with nothing but grit and an $8 electric fan. Hoo boy he made those expensive college boy consultants look like they just fell off the turnip truck.

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

#242

Post by wavegeek »

pault wrote: post #221
Stubb wrote: post #87

Earlier quoted context omitted.

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.

I've never heard of this. How can a hydrocarbon fuel be carbon neutral?

You take CO2 out of the air and turn it into oil / methane / elemental carbon using vast amounts of energy and some water and catalysts.

You then burn it, returning it to the atmosphere.

Net CO2 impact = zero.

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

#243

Post by _Microft »

pault wrote: post #221
Stubb wrote: post #87

Earlier quoted context omitted.

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.

I've never heard of this. How can a hydrocarbon fuel be carbon neutral?

The problem is not that we are burning hydrocarbons per se. The problem is rather that these hydrocarbons were extracted from the ground and introduced into the short term carbon cycle. The total amount of carbon rises thereby which leads to shifts like an increasing concentraction in the atmosphere and the oceans. These higher levels of carbondioxide in the atmosphere let less heat escape back into space (the atmosphere is normally somewhat transparent at the affected wavelengths but carbondioxide can absorb at that, trapping additional heat in the atmosphere, see [0]), leading to additional global warming (water vapor also traps heat and and made Earth suitable for life as we know it in first place). Higher levels of carbondioxide in the atmosphere also lead to more carbondioxide being absorbed by the oceans which in turns acidifies the water.

We could extract carbondioxide from air, turn it into hydrocarbons and burn that all day/year/century long but producing it from fossil sources is what makes it so bad.

[0] https://en.wikipedia.org/wiki/Greenhouse_effect#/media/File:...

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

#244

Post by barry-cotter »

frequentnapper wrote: post #240
sheeshkebab wrote: post #215

Earlier quoted context omitted.

I guess we can ask Huawei about how easy it is to build computers in 2020...

with stolen blueprints and unlimited govt resources, easy as pie...

Not really. After the collapse of the Soviet Union China bought complete blue prints, working models and the time of engineers who had designed Soviet combat aircraft and I believe other military hardware. They still couldn’t replicate them. A tool chain and manufacturing ecosystem is a unit. Industrial espionage is useful but it’s not a way to leap frog 20 steps, maybe four, ten if you’re both lucky and good.

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

#245

Post by Xylakant »

pault wrote: post #221
Stubb wrote: post #87

Earlier quoted context omitted.

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.

I've never heard of this. How can a hydrocarbon fuel be carbon neutral?

In a nutshell: You taken carbon dioxide from the air, hydrogen produced with a carbon neutral power source and reverse the process of burning oil. Result: hydrocarbon and oxygen. Costs a fair amount of energy and is comparatively inefficient and costly, but it is carbon neutral since burning that produced hydrocarbon will produce as much CO2 as you used to produce it.

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

#247

Post by barry-cotter »

rrdharan wrote: post #207
ada1981 wrote: post #159

Earlier quoted context omitted.

This is a great mental model. I'm curious about applying this in areas of one's own life. Certain things that you'd actually accomplish faster, by starting later and leveraging the compounded time / resources that would have been spent pursuing it earlier.

The 80,000 hours folks generally apply this kind of reasoning to explain why it’s better for most people to just focus on a corporate job, stockpile a ton of cash, and donate it all when you die, instead of quitting to join a cause / non-profit - if your only goal is to optimize your impact. Obviously people are free to choose differently and there are exceptions, unique circumstances etc.

I’m reasonably confident your summary of their advice is out of date. They now believe most organizations are talent constrained and the difference between the best and second best candidate is often very large so most people should be trying to work on hard problems fast if they can.

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

#249

Post by m0zg »

ClumsyPilot wrote: post #183
m0zg wrote: post #109

Earlier quoted context omitted.

Just the little bit responsible for Chernobyl and Fukushima is not a part of the design at all. No big deal. :-)

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.

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

#250

Post by hyperion2010 »

Robotbeat wrote: post #204
maccam94 wrote: post #199

Earlier quoted context omitted.

Timeline (in case you want to skip over some parts): 00:01:00 - introducing Dennis Whyte, MIT department head for nuclear science 00:04:24 - presentation starts 00:06:00 - identifies breakthrough with REBCO magnets 00:07:25 - explains deuterium-tritium fusion 00:12:30 - basic metrics for reactor performance 00:17:15 - energy output of other previous fusion experiments 00:19:00 - examines ITER and the problems of its…

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

Buried in the wiki page for YBCO is a note that REBCO is a synonym of sorts. The superconducting tapes that are discussed in the talk thus would seem to be YBCO.
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