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Nuclear-fusion reactor doubles record for energy made from fusing atoms

nature.com

201–210 of 282 posts

Re: Nuclear-fusion reactor doubles record for energy made from fusing atoms

#201
post #48

Earlier quoted context omitted.

I agree that solar/wind price points have massively gone down but how is storage a solved problem? I have only seen research projects in this field, is there anyone who has commercially deployed an energy storage solution? (other than hydro projects)

The only problems we have with storage are (1) determining which will end up cheapest, or has the most valuable side benefits, and (2) building out. Hydrogen, anhydrous ammonia, and liquified air all produce a valuable industrial product once the tanks are full. Used to be their round-trip efficiency was considered too low, but with solar panels getting dirt cheap, just putting up more panels accommodates almost any…

> China is even building cables to Chile (!)

Where did you read this? China is 18000 km from Chile, so this seems really unlikely.

Re: Nuclear-fusion reactor doubles record for energy made from fusing atoms

#202
post #92

Earlier quoted context omitted.

Sure, but then the poster said that we can't allocate labor to this specific goal without taking it away from that specific goal. Why would that be true? Energy supply takes a minuscule fraction of our total labor, and nothing stops us from supporting fusion without unsupporting solar. Or am I missing something?

The argument is that it would be far more effective to take all of the allegedly wasted fusion research money and spend it immediately on wind and solar. No one knows the future but with the way things have gone so far, fusion in its current form looks like a giant waste of time and money.

Yeah, I'm not really seeing the justification for that argument, especially not when expressed as a dichotomy.

Re: Nuclear-fusion reactor doubles record for energy made from fusing atoms

#203

Earlier quoted context omitted.

> they were being used in one direction in the comment That's not correct at all. The simple-minded heuristic is along the lines of "technology is bad" or "this new thing will never work". But the dream of fusion as "too cheap to meter" has been going on for 70 years. The comment you're replying to wasn't talking in general terms, but had specific critique of both the long track record and the practical utility of th…

I will let other readers of this thread judge for themselves.

I am asking you to judge for yourself. In particular, to recognize that not only did you ignore his specific critique, you have now ignored mine.

Re: Nuclear-fusion reactor doubles record for energy made from fusing atoms

#204

Earlier quoted context omitted.

What a terrible argument. A global energy supply system is a huge thing. That means it will make sense to spend literally trillions of dollars on it. This will mean building enormous capacity to build its components, including as many battery factories as we need.

Once we agree that the solar + wind solution will cost trillions and take decades to scale up anyway, the benefits of fusion start to shine through. We may as well invest all that time and money in scalable production that doesn't exhaust the earth's supply of natural resources.

What benefits? The fusion solution would be even more expensive, and not available for decades, if ever.

Re: Nuclear-fusion reactor doubles record for energy made from fusing atoms

#205

Earlier quoted context omitted.

> fission reactors are today not competitive, and get less competitive by the day No, we are just incompetent idiots. This has nothing to do with fissions and everything to do with degradation of contruction and practical egnineering skills - now it takes 30 years and 100 billion dollars to make a small railway in California. Victorian England or China could do this without much trouble. The english-speaking western…

The west’s engineering skills are not in decline, though if you have a metric that indicates that, it would be interesting. Europe has not had USA-level problems with building a popular rail network, or other major works. The main differences in costs and time from 150 years ago are: (A) Accounting for Extrinsic Costs. as the nations have become more dense and more democratic, peoples voices need to be heard. Environ…

One thing I would like to support in your statement is (A)The Extrinsic Costs. This was not accounted for in China and is shaping up to be a very volatile national issue for them for their Railways.

https://www.orfonline.org/expert-speak/chinas-high-speed-rai...

https://factsanddetails.com/china/cat13/sub86/item1848.html

Re: Nuclear-fusion reactor doubles record for energy made from fusing atoms

#206
post #17

As much as I enjoy reading this news. It is feels heavily sensationalized. "Smashes" the energy record. We're talking about a fusion generator here, that after 25 years of work, now manages to output 'double' the energy, to 59 MJ in 5s -like 20 MW- while requiring 180 MJ input power. Somewhere hidden in the article is the news that this could mean a input/output ratio of 10 in a full scale reactor, but that's also so…

Nope, this is good news. JET is a 1980s research project into how to contain a plasma and squish it enough to achieve fusion at all, not a practical generator. It doesn't have superconducting magnets, it runs on big lumps of copper, with limited cooling and no way of recovering output power. In the latest run, they achieved fusion and kept it running until JET ran out of power for its magnets . The plasma didn't touc…

Correct me if I’m wrong but the neutrons eventually cause the reactor to eat itself as well, don’t they? Unless you can build a sacrificial layer inside to absorb all the damage you have to keep building new ones, even if it weren’t radioactive.

Re: Nuclear-fusion reactor doubles record for energy made from fusing atoms

#207

Earlier quoted context omitted.

The argument is that it would be far more effective to take all of the allegedly wasted fusion research money and spend it immediately on wind and solar. No one knows the future but with the way things have gone so far, fusion in its current form looks like a giant waste of time and money.

Yeah, I'm not really seeing the justification for that argument, especially not when expressed as a dichotomy.

Have you really never had to choose between spending money on this or on that?

Few lack that experience.

Re: Nuclear-fusion reactor doubles record for energy made from fusing atoms

#208
Here's an interesting article that puts this into perspective and provides a lot of history about nuclear research:

https://quillette.com/2022/02/21/fusion-power-is-coming/

EDIT:

The above article talks about some other approaches, such as:

> MIT physicist Bruno Coppi proposed achieving fusion in a very small tokamak by the simple expedient of using ultra-strong magnetic fields. The magnetic field lines of a tokamak confine particles to follow them, spiraling around the chamber, with the radius of the spirals being inversely proportional to the strength of the magnetic field. Coppi reasoned that the relevant dimension of a tokamak was not its size per se, but the ratio of its size to the radius of the spiral, because it is this ratio that determines how long a particle will last before it hits the wall. Furthermore, as noted above, the higher the magnetic field strength, the faster the particle is likely to react. So if you want a particle to take part in a fusion reaction before it hits the wall (which would cool it too much for fusion), the key is just to go for broke with ultra-powerful magnets. But the problem is that the highest magnetic field it is practical to achieve with traditional low temperature superconducting magnets is about 6 Tesla, and Coppi needed 12 T. So, he designed an experimental machine called “Ignitor” using copper magnets. This could not be a practical commercial reactor, because the resistive copper magnets would use too much power. Nevertheless, if it had been built, we probably would have achieved thermonuclear fusion ignition in the 1990s. But all of the US Department of Energy funds were committed to ITER, so Ignitor was never built. But starting around 2014, an MIT group led by Professor Dennis Whyte decided to pick up where Coppi had left off, improving on the Ignitor concept by making use of high temperature super conductor magnets, which require no electric power and can reach 12 T. As a result, with more than twice the magnetic field strength as ITER, the CFS reactor, known as SPARC (for Smallest Possible Affordable Robust Compact) fusion reactor, will achieve 1/5th the power hoped for by ITER in a reactor 1/65th the volume. Furthermore, CFS aims to do it by 2025, achieving in seven years what ITER hopes to do in half a century.

Re: Nuclear-fusion reactor doubles record for energy made from fusing atoms

#210

Earlier quoted context omitted.

So don't use batteries. Pumping water uphill is still the most efficient large-scale technology for electrical storage.

Pumped hydro is a lot more promising than batteries for sure, in that current capabilities is off by a factor of a thousand instead of a million. The largest pumped hydro station[1] provides up to 24 gwh of storage. So three thousand of these stations (costing $12 trillion) would store one day's worth of electricity. [1] https://en.wikipedia.org/wiki/Bath_County_Pumped_Storage_Sta...

Agreed that pumped hydro is the most efficient storage solution but it's limited by geography: You can only do it where there's an existing significant elevation change. Building a sufficiently elevated lake artifically by heaping thousands of cubic kilometers of dirt is not cost-effective. That is, the energy that would be required to build it would vastly exceed the total energy it could store integrated over its lifetime.
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