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ITER: World's largest nuclear fusion project begins assembly

bbc.co.uk

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Re: ITER: World's largest nuclear fusion project begins assembly

#301
post #192
post #160

Earlier quoted context omitted.

Renewables are only safer and cheaper bet once the battery issue is solved and can be made equally green, safe and cheap. The primary reason why nuclear isn't commercial viable today is that combining natural gas and renewables makes for a very cheap energy grid.

Nope. There are other alternatives, and grid scale batteries are viable now. Just cheaper to burn gas/coal and fsck the future! The obvious alternative is pumped hydro, that is well established. Another is demand management, unexplored because the greed heads in control do not believe that our society can work together for the common good. Coming from Aotearoa, as I do, I know that is a fat lie.

Another alternative is to just build so many renewable energy plants that demand can be served even when production is comparatively low. During peak production hours, you can just blow the energy back into the atmosphere (or run a steel mill with it). This is a question of political will, and nothing more.

Re: ITER: World's largest nuclear fusion project begins assembly

#302
post #7

I am going to need some help on this one as my knowledge on physics is limited: What makes scientists believe that the solution to nuclear fusion power is only a matter of scale? I desperately want nuclear fusion to work because nuclear power is the only realistic way to solve the looming energy crisis of the 21st century while still maintaining the same standard of living for everyone. It's also 500% more important…

>I desperately want nuclear fusion to work because nuclear power is the only realistic way to solve the looming energy crisis of the 21st century while still maintaining the same standard of living for everyone.

If that's all you care about we can do without nuclear fusion. We have a sun in our neighborhood so we can just harness its energy in various forms such as wind, fossil fuels, biomass or via PV. The real reason we need nuclear fusion is because it is necessary for interstellar travel. There's no sun in deep space. You'll have to bring your own fusion reactor with you.

Re: ITER: World's largest nuclear fusion project begins assembly

#303

What does HN crowd think of companies like hb11 or lppfusion which try to construct much smaller but still powerful (lpp plans for 5MW, relatively small, reactor. They also want to use a different fuel that produces very little neutrons, thus very low radiocativity. And moreover they do not need thermal part as electricity is generated by directly collecting alpha particles (and some Xrays IIRC). It _feels_ to me lik…

Someone below mentioned the following link, in which they do a sharp comparison of fusion technologies. I am by no means an expert, but after watching that link, it appears to me that such solutions are probably unproven science: it took over 50 years to get anywhere near a Q-factor of 1 (energy in = energy out), with hundreds of technologies screened, tested and scrapped.

    https://www.youtube.com/watch?v=L0KuAx1COEk

Re: ITER: World's largest nuclear fusion project begins assembly

#304
I'm surprised that we're still chasing moon shots in strong force fusion, while weak fusion, which has actually been demonstrated already, gets little attention. Chemically assisted/low energy nuclear reactions have been proven to produce clean energy and useful transmutation. This process can be used to turn radioactive waste into inert material. For example, technetium-99 is a particularly pernicious by-product of nuclear fission. It has a half-life of ~200,000 years and is very mobile in the atmosphere, making it difficult and expensive to handle. In a CANR reactor, this nuclear waste is converted into the safe, and valuable, palladium-106, and the by-product is clean heat. Given the double benefit of clean fuel and nuclear waste recycling, I think this should be a bigger priority than strong-force fusion.

http://nautil.us/issue/86/energy/einsteins-lost-hypothesis

https://www.jstor.org/stable/24216601?seq=1

https://www.sciencedirect.com/science/article/pii/B978012815...

Re: ITER: World's largest nuclear fusion project begins assembly

#305

Earlier quoted context omitted.

Maintain a fusion pulse for up to 8 minutes What does this mean?

Tokamak-style reactors like ITER rely on a rapidly-changing magnetic field to induce an electric current in the plasma, for stability of the plasma. The magnet that provides this rapidly-changing field (the 'central solenoid') can't keep increasing in field strength indefinitely -- so there's a time limit to the life of the plasma. There are other ways to supplement the current in the plasma, which can help extend th…

But this is beyond ridiculous, so many years of R&D for 8 minutes of sustained acticivty activity? That sound like a joke

Re: ITER: World's largest nuclear fusion project begins assembly

#306

What does HN crowd think of companies like hb11 or lppfusion which try to construct much smaller but still powerful (lpp plans for 5MW, relatively small, reactor. They also want to use a different fuel that produces very little neutrons, thus very low radiocativity. And moreover they do not need thermal part as electricity is generated by directly collecting alpha particles (and some Xrays IIRC). It _feels_ to me lik…

I worked on Gene - a gyrokinetics app used to study fusion reactors - and I fondly recall helping a colleague debug one of their simulations in which they set a boundary condition incorrectly; that simulation ran for two weeks before the mistake was found. We estimated this mistake to have costed the tax-payer multiple millions of dollars _in electricity costs_ (just from the core's that were used, their wattage, and the time duration; which is a fraction of the cost of acquiring and operating a super-computer).

All our fusion models that correctly predict all the results produced by all the fusion reactors that have been built to date predict that ITER will work.

I have no idea whether these models predict that these other reactor designs will also work. What I do know is that one needs _many_ simulations to study that, and the costs of doing that feels absurdly out-of-reach for any startup. One does not only need to "verify" a design, but come up with it, optimize it, etc. as well as gaining access to the supercomputing resources or buying and maintaining their own supercomputer. That puts the initial investment already in the millions.

OTOH, a startup that checks a design that has been created, optimized, and verified in academia and whose goal is "only" to build it, would require a smaller investment, but no idea how big this investment ought to be.

Re: ITER: World's largest nuclear fusion project begins assembly

#307

Earlier quoted context omitted.

This is why I'm particularly upset about SSC's[0] failure to be built. There are many advantages to housing the smartest scientists in the world within the borders of your country, and those benefits aren't limited to scientific output. After all, a big part of these multi-national projects is the culture war. And let's be real, which is worth more? A super collider that runs for decades or the F35 (which cost more,…

My software startup was a huge beneficiary of the SSC cancellation, it freed up a nuclear physicist to write graphics software for us, which became one of our biggest products. I’m in favor of pursuing basic research, but there is always a cost. When you take a group of your smartest people and focus them on non-economic activities, the economy loses something.

I mean, that nuclear physicist also wasn't farming.

Re: ITER: World's largest nuclear fusion project begins assembly

#308

Earlier quoted context omitted.

Its pretty presumptuous to assume your startup has economic value, and the SSC didn't. Plenty of completely economically worthless tech startups.

Well, ours was profitable and sold for $95M, kind of a definition of economic value.

That startup was already sold?

Re: ITER: World's largest nuclear fusion project begins assembly

#309

I'm surprised that we're still chasing moon shots in strong force fusion, while weak fusion, which has actually been demonstrated already, gets little attention. Chemically assisted/low energy nuclear reactions have been proven to produce clean energy and useful transmutation. This process can be used to turn radioactive waste into inert material. For example, technetium-99 is a particularly pernicious by-product of…

So you suggest that they should dump nearly 2 decades of work because there is something else which seems to be a potential energy source? The ITER project was founded in 2007. From there on hundreds of physicist, chemists, engineers and computer scientists started planning this RESEARCH project in order to better understand this kind of technology. Shouldn't we stick to what we have started (since this is (more than) cutting edge technology) and have a look at other technologies in parallel?

Re: ITER: World's largest nuclear fusion project begins assembly

#310

Earlier quoted context omitted.

Without giving a strong opinion either way on whether this particular project is a good investment or not : Science, as an institution imo undervalues good marketing and good PR. For profit enterprises are under no illusion that they can succeed without good marketing and public perception. If large expensive projects like this are needed to increase public awareness and support for basic scientific research then I a…

I think a problem with ITER for PR isn't the cost. It's time. I learned about it and got excited more than a decade ago. It'll still take years of time for it to be finished. I'm not really sure how to express this, but the huge amount of time just diminishes the impact of it for me.

There are people whose imagination ITER exceeds.
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