Sciencemadness Discussion Board

ITER: A useful nuclear fusion experiment or a waste of money ?

metalresearcher - 28-11-2023 at 09:46

Seen a lot of videos on this project comprising on nuclear fusion using a gargantuan building in the south of France. It looks very interesting, but I have my doubts / questions.

* 'fusion like the Sun and stars' No, the stars don't fuse deuterium and tritium. The real thermonuclear processes running in stars are unattainable with current technology.
* Neutrons. The reaction releases lots of neutrons, bombarding the reactor shell to radioactive isotopes and thus generating nuclear waste. Not as much as fission reactors, but not free of nuclear waste.
* Tritium is very rare and hard to breed.
* Competing processes like the inertial confinement and aneutronic fusion (e.g. boron - proton) deliver electricity directly without heat. ITER still produces heat which will be dissipated and not converted to electricity. Nothing is known what ITER wants to do when it does run successfully: a controlled fusion reaction with a Q = 10 (and I mean a real Q, including *all* energy powering magnets, etc. required to run it.)

The plan is that it will be succeeded by DEMO, a commercial fusion plant starting in the 2030s and ITER to be decommissioned. What a waste of money (?)

Will it be demolished or converted to a museum ?

Sir_Gawain - 28-11-2023 at 10:22

As far as I know, you can solve problems 2&3 by lining the fusor with lithium. It will absorb neutrons and release tritium.

Dr.Bob - 28-11-2023 at 18:03

I would agree that many of the big fusion plans stated are not very practical, the capital costs of a plant would be many billions, and the convertion of heat to electricity would be still at moderate efficiency. The cost of solar, wind, and other energy sources are now lower than fusion would likely be, and work now. As much as I still agree that some constant baseload of electric is needed, as battery storage is not practical yet, I don't see fusion, especially the big systems, being a good source now. If we spent the amount on various fission systems that we have on fusion, we could already have doubled the power from fission by now. If we could combine more efficiency efforts with 20% more fission, then solar and wind and such could fillin the rest pretty well.

j_sum1 - 28-11-2023 at 22:43

My view is that fusion, or more specifically reaching break-even harnessed energy is unlikely to ever be reached. Or if it is, the capital costs are likely to be astronomical; rendering it impractical in any realistic context. It is a fun idea to play with and has some scientific merit - in the same way as superheavy element research and deep space probes have scientific merit. But there comes a time when the costs cannot be justified. And for fusion, I suspect we are about to reach that point.

averageaussie - 29-11-2023 at 14:44

Quote: Originally posted by Sir_Gawain  
As far as I know, you can solve problems 2&3 by lining the fusor with lithium. It will absorb neutrons and release tritium.


I'm not to sure on that one.
Normally, only lithium-6 (40% of lithium) releases tritium and helium when hit by a neutron, and lithium-7 (60%) just absorbs and releases the neutron, leaving the lithium shell mostly fine. only if the neutron absorbed is under 2.47 MeV. the neutrons released by deuterium-tritium fusion are well above that, 14.1 MeV. This was why castle bravo went from the 5 megatons of expected yield to 15, triple the yield from 60% more lithium releasing tritium and neutrons.

so not only would the lithium shell very quickly melt due to the heat of the nuclear reaction, but would also turn itself into lots of tritium, which can cause all sorts of problems (reacting with extra deuterium if extra was put in, excess contamination, who knows what else tritium does in the conditions found inside a fusion reaction.)

clearly_not_atara - 30-11-2023 at 11:24

Yes and no. Yes, ITER was valuable as conceived: a collaboration between the United States and the Soviet Union (with a few junior partners) to build an experimental fusion reactor. The experimental nature of the project is not a demerit: the dynamics of plasma remain poorly understood and the way that fusion heating would affect those dynamics is also poorly understood. It's quite likely that an attempt to immediately build a functioning power plant would be an expensive failure.

No, because ITER's design and management have suffered from two serious errors that delayed the project and made it much more expensive:

- the Soviet Union, which actually originated the idea, collapsed. Subsequently the project moved slowly and then took on several new member nations which created more bureaucracy and buck-passing

- the project did not attempt to use high-temperature cuprate superconducting magnets, even though these come with massive cost advantages. At the outset, it was not known how to make these materials into usable electric cables, but it was eventually figured out, and by now there are major superconducting infrastructure projects based on BSCCO and ReBCO ribbons. This not only makes the construction much more difficult, it limits the generalizability of the findings, because any real fusion reactor is likely to take advantage of high-temperature superconductors.

So overall, sadly, it sucks.

Mateo_swe - 17-4-2024 at 03:29

ITER is a huge waste of money, thats my oppinion.
The idea that going bigger will solve problems and make it work i think is completly wrong.
They will just find that new problems have arised from the up-scaling that wont make it work.
The money spent on ITER is astronomical and it will probably not work anyway.
They really should spend the money on smaller system ideas instead, then very many ideas can be investigated.
It´s going to be some new, radical and completly different (probably small) solution that will finaly make it happen.
But how long inte the future? Probably quite a while as most funds for these things are wasted on projects like ITER.

Sulaiman - 17-4-2024 at 03:48

It is easier to monopolise a market when potential competitors are excluded from funds and/or knowledge.

Sir_Gawain - 17-4-2024 at 09:13

While it is very interesting from a scientific perspective, I think the money could've been put to a better use by improving fission power generation. It's a technology we've had for a while, and it sure works. Most of the arguments I've heard for fusion over fission aren't very valid. For example, nuclear waste isn't as big of a problem as most people think. And, as metalresearcher pointed out, fusion isn't completely clean either. The argument for the availability of hydrogen vs. uranium is ridiculous. We're not going to run out of uranium. It's about as scarce as tin.

Keras - 17-4-2024 at 11:24

Quote: Originally posted by Mateo_swe  
ITER is a huge waste of money, thats my opinion.


I tend to agree. Controlling a plasma in fusion is probably a nightmare. It might work for a few milliseconds, but on a larger time frame, linear flow seems impossible to be maintained. Turbulences, stray magnetic currents and incontrollable particle motion will surely develop, and break the confinement – and maybe tear the magnetic bottle apart, which could result in dire consequences.

Magnetohydrodynamics, which is the discipline that looks into plasma forces and motion, does not really understand turbulences – even less that hydrodynamics.

Besides, I've heard that the fission reaction produces neutrons that will hit the walls and induced them to become radioactive. Targeting a truly clean reaction, like the famous triple alpha process, would require reaching 100 million degrees, which is currently just a pipe dream.

Keras - 17-4-2024 at 11:28

Quote: Originally posted by Sir_Gawain  
We're not going to run out of uranium. It's about as scarce as tin.


Unfortunately, there’s not enough uranium in the Earth's crust to provide for all the electricity currently used in the world.

Thorium could be a useful alternative, and there are scientists advocating for its use. It is more abundant than uranium, and doesn’t need enrichment, IIRC. It could also be used to recycle uranium fusion waste.

The reason why uranium was initially favoured over thorium is that the thorium chain doesn’t produce plutonium, so was unsuitable to get nuclear payload for bombs.

[Edited on 17-4-2024 by Keras]

Dr.Bob - 18-4-2024 at 06:59

We don't need enough uranium to power the entire Earth, just enough to provide baseload at night and on cloudy days and windless days. If we either cut our electric use by 50% or built a few dozen more fission reactors, we could shut down most fossil fuel power plants, which would save those resources for making plastics and other useful chemicals. We can find enough uranium and thorium to last decades easily enough, and more with reprocessing of waste.

Since nuclear works currently, it is better than fusion, which I have been hearing will work in another 10 years since the 1970's. Regardless of your opinion on climate change, there is not enough coal, oil and gas to run the Earth on for another 100 years either, so we need to find better sources of power, as fossil fuels are limited, create pollution, and have growing costs.

Precipitates - 18-4-2024 at 18:15

Right now it seems some western governments have the idea that fusion is going to come along and solve everything.

I found this lecture frustrating. We have proven technologies that we can use to generate the necessary power, we don't need to rely on some hero technology that may or may not work, at least in the short-term. Yes fusion may work in 50-100 years, but how much damage will have been done by then?

And there is certainly the argument that some of the money spent on these physics experiments could be put to better use.

Just my two cents anyway ;)

Twospoons - 18-4-2024 at 18:53

Quote: Originally posted by Precipitates  

And there is certainly the argument that some of the money spent on these physics experiments could be put to better use.


I suspect the money spent on fusion research is insignificant next to the money spent on militaries around the world. That's where the real waste is. The US annual military budget runs north of $700bn.
The Ukraine war alone has been estimated at $40bn, just on direct military cost - the economic costs are even higher. All thanks to bone-headed greed and stupidity.

So clearly there's plenty of money sloshing around, its just that humans seem to prefer using it to blow each other up, rather than advance civilization. /rant

Personally I think fusion research is money well spent. It advances science and hopefully unlocks a new energy source. We may not need fusion right now, but we will in the future, so we need to do the research now.

We need to get back to long term thinking. The stone masons laying the foundations for those old cathedrals knew they would never live to see the thing completed. Yet cathedrals got built. We need to adopt the same attitude.


[Edited on 19-4-2024 by Twospoons]

[Edited on 19-4-2024 by Twospoons]

Precipitates - 18-4-2024 at 20:38

Quote: Originally posted by Twospoons  


I suspect the money spent on fusion research is insignificant next to the money spent on militaries around the world.



Definitely, but which countries are willing to give that up, sigh.

Quote: Originally posted by Twospoons  


Personally I think fusion research is money well spent. It advances science and hopefully unlocks a new energy source. We may not need fusion right now, but we will in the future, so we need to do the research now.

We need to get back to long term thinking. The stone masons laying the foundations for those old cathedrals knew they would never live to see the thing completed. Yet cathedrals got built. We need to adopt the same attitude.



But they weren't living through times of such marked change. The research definitely needs to be done, just I wonder if now is the right time. There was an interesting discussion on the money spent on particle physics broadcast a few weeks ago.

Indeed fusion is a grey area, as if they finally did crack it, it would help solve our energy problems.

Keras - 18-4-2024 at 23:05

Quote: Originally posted by Dr.Bob  
If we either cut our electric use by 50% […]


I think this is the key. Power consumption MUST be reduced. I’m really not certain we can have fusion any time soon, unless a totally groundbreaking discovery allows us to dramatically reduce the constraints.

On a more positive note, the solution might come from Inertial confinment fusion, either from laser or z-pinch, like the Z-machine of Sandia Labs.

phlogiston - 19-4-2024 at 04:22

It's a useful endeavour if only for the learning process. Hardly any of our personal mad scientist experiments is going to benefit the world in any real way, yet it is still useful to do, for learning and educating ourselves and gaining experience from the challenge. On a giant scale, ITER is useful for similar reasons. Because of the intellectual and technical challenge it presents, for stimulating international collaborations. As a bonus, it may yield technology that is useful elsewhere too. Even if it won't ever lead to a useful energy source, I'd say it is at least as well spend as the money going to the international Space Station ISS (which costs an order of magnitude more) or the Large Hadron Collider (LHC).

Inertial confinement fusion and Z-pinch machines are also interesting for similar reasons, but even less likely to ever produce useful fusion energy than ITER.

[Edited on 19-4-2024 by phlogiston]

unionised - 19-4-2024 at 15:43

A useful nuclear fusion experiment or a waste of money ?

A quick thankyou to all the people who think they know if an experiment is going to be useful a year or more before it finishes.

Does anyone have next week's lottery numbers?