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Nuclear "con" Fusion.

George J

George J

Herefordshire member
Without doubt the human race needs to find a method, or indeed many methods, of generating copious amounts of CO2 neutral electricity that is sustainable. I hate the idea that sustainable energy conversion is called renewable. Energy is not renewable, but everything, energy-wise, is towards entropy, but not in our lifetimes, or indeed the lifetime of our sun.

Fusion has always been [in my lifetime] twenty years in the future. It was twenty years in the future in the 1970s, and still is today!

It seems the whole premise may be misguided ...

I watch the estimable Sabine Hossenfelder, and her latest YouTube film makes some points that are not otherwise widely known.


Please do watch right through. The issues are all about not telling the whole truth about what is possible in terms of basic physics on Earth [rather than in the sun], and poses a remarkable question about the confusion on the topic.

Just tuppence' worth and very best wishes from George
 
You can’t dismiss stuff because it seems improbable. The amount of research seems appropriate for the likely outcome which is quite poor at present. But to just close it from funding is ignoring the surprises of science over time.
 
ITER has always been intended as a very, very expensive laboratory tool. It will never be even a demonstration reactor. The first run (2025?) is primarily designed to show "something" to the politicians to get funding for the next stages, which will be about setting the design parameters (materials, dimensions, control algorithms etc.) for a further prototype called DEMO. Full power operation at ITER in 2035, if all goes well. Even then, ITER will only be running hot plasma a few minutes per day and won't convert heat into electricity.
DEMO will run a few hours per day to demonstrate how to get heat out of of the core and generate electricity from it. Once that is done, the data collected will enable the next stage PROTO to be designed... PROTO will be designed to run full time. Only then will it be possible to have a clear view of operating costs and commercial viability. DEMO is planned to begin operation in 2051 at the earliest... but each major participant seems to have its own ideas and plans to build its own.

It's not a conspiracy. It's just a really complicated project, a bit of a long shot bringing together some of the planet's best scientists and engineers to see if the idea is viable. It probably won't be, but all the world's technology powers want a seat at the table just in case it is. The challenges are huge (plasma temperatures of 150 million C, daunting material and control issues) so even if it works it may not be commercially viable.

Optimistic view here:https://e.issuu.com/embed.html?d=2020_iter_annual_report&u=iterorganization (timeline on p. 33)
One of the many skeptical views here (almost 5 years old, but hey): https://thebulletin.org/2017/04/fusion-reactors-not-what-theyre-cracked-up-to-be/
 
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I remember reading this BBC article in August and - as always, but possibly, just maybe - it might actually happen in our lifetime (well, some of our lifetimes; I'm 48 so I might yet live to see it).
 
Fusion research is of the utmost importance in my view. The promise of clean limitless energy is a true Panacea for the human species and most of Earth's other life.

I do however agree that in recent years more and more is being made in the media about progress which is actually very slow and very limited.

Fission is proven, here and relatively easy and cost-effective. The green movement need to embrace this with the same zeal as wind and solar.

Research, the ability to allow the best people to think about ways for us to live better and overcome problems relies on a thriving civilisation which in turn requires energy.
 
What a ridiculous title, implying a 'con'. A 'con' is short for a confidence trick. Is the suggestion that some of the world's leading physicist and engineers are embarking on projects to fleece governments of money? Fusion is real, but building a working fusion reactor is incredibly difficult. If workable fusion can be achieved then that would change the world. I would suggest people actually inform themselves rather than waste time on cheap shot videos.

My money is on a Tokamak type solution:

https://ccfe.ukaea.uk/research/step/
 
Just to add, I do like Sabine she's a very engaging presenter and I really like her videos which are very informative. She is of course right about Q-plasma vs Q-total, but overall the video's tone is negative and unnecessarily so imo. She could have ended it on a more positive note.
 
I think it's entirely reasonable to approach the Q-plasma problem before the wider Q-total problem. If anyone's confused, it is the presenter who doesn't seem to appreciate how such problems are progressively broken down and resolved.

ITER hopes that scale will be decisive, and I'm following it with interest, as well as other approaches - this company, for example. Up to a decade ago, the joke was that fusion was always 30 years away, but that timescale does seem to be reducing significantly now. We should know by 2025 if a viable, scalable commercial solution can be established.
 
Tantris said:
If anyone's confused, it is the presenter who doesn't seem to appreciate how such problems are progressively broken down and resolved.
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You seem to have missed the point. That being that something like a 20-fold increase in conversion efficiency is required just to break-even. That would be one seriously, seriously large improvement due to scale alone.
 
PsB said:
One of the many skeptical views here (almost 5 years old, but hey): https://thebulletin.org/2017/04/fusion-reactors-not-what-theyre-cracked-up-to-be/
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Thanks for posting this. I'd never come across these problems which have stopped me in my tracks. The nuclear proliferation argument in my view is a red herring and most easily mitigated. The neutron stream damage is the most likely show stopper. I heard somewhere, that moon dust is full of tritium adsorped from the sun.

It's amazing that even with these daunting problems to overcome Fusion research is marching on.
 
I think fusion is pie in the sky and will not be a commercial prospect for many many decades and possibly never.

Build fission reactors and make much more use of the free fusion reactor in the sky, is the realistic way forward.
 
nostromo said:
Thanks for posting this. I'd never come across these problems which have stopped me in my tracks. The nuclear proliferation argument in my view is a red herring and most easily mitigated. The neutron stream damage is the most likely show stopper. I heard somewhere, that moon dust is full of tritium adsorped from the sun.

It's amazing that even with these daunting problems to overcome Fusion research is marching on.
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The recent experiments at Culham appear to have mitigated that problem.

“Initial results from UK Atomic Energy Authority (UKAEA)’s new ‘MAST Upgrade’ experiment at Culham have demonstrated the effectiveness of the so-called Super-X divertor, an exhaust system that will allow components in future commercial tokamaks to last longer and bring costs down.”

https://www.theengineer.co.uk/exhaust-divertor-ukaea-nuclear-fusion-super-x-divertor/
 
Cav said:
I think fusion is pie in the sky and will not be a commercial prospect for many many decades and possibly never.

Build fission reactors and make much more use of the free fusion reactor in the sky, is the realistic way forward.
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Not sure “pie in the sky” is the phrase I would use but otherwise, yes I agree; with the caveat that research in fusion should continue.
 
russel said:
The recent experiments at Culham appear to have mitigated that problem.

“Initial results from UK Atomic Energy Authority (UKAEA)’s new ‘MAST Upgrade’ experiment at Culham have demonstrated the effectiveness of the so-called Super-X divertor, an exhaust system that will allow components in future commercial tokamaks to last longer and bring costs down.”

https://www.theengineer.co.uk/exhaust-divertor-ukaea-nuclear-fusion-super-x-divertor/
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While that is brilliant news and shows how any problem can be overcome. The fast neutrinos produced by fusion are not easy to control and will make every material close to the plasma radioactive as I understand it. The most promising mitigation is a 1 meter deep liquid lithium sphere around the plasma. This of course has its own dangers. I'm hopeful the boffins at Culham and elsewhere will work it out. The long term future of life may be dependent on their success.

From memory we have enough Uranium for Fission to power civilisation for many hundreds of years so we have time to work out fusion.
 
nostromo said:
From memory we have enough Uranium for Fission to power civilisation for many hundreds of years so we have time to work out fusion.
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230 years or thereabouts is the current estimate: https://www.scientificamerican.com/article/how-long-will-global-uranium-deposits-last/

Of course, Uranium is only one fuel (https://en.wikipedia.org/wiki/Thorium-based_nuclear_power) but to use alternatives would require massive investment to put in place a whole new infrastructure required to support its use.
 
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Not only Thorium, but spent fuel could also be an option. This idea from a Silicon Valley startup looks interesting - micro reactors powering at a district level, using spent fuel. The biggest single obstacle looks likely to be security. Nuclear will always be a magnet for terrorists.
 
Sue Pertwee-Tyr said:
Not only Thorium, but spent fuel could also be an option. This idea from a Silicon Valley startup looks interesting - micro reactors powering at a district level, using spent fuel. The biggest single obstacle looks likely to be security. Nuclear will always be a magnet for terrorists.
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Security, logistics, safety, trained and competent engineers. Long-term considerations for disposing of reprocessing waste and of reactors at end of life.
 
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