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Chinese Tokamak reaches over 100M degrees

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Re: Chinese Tokamak reaches over 100M degrees

#51

Post by Someone »

miemo wrote: post #41
txcwpalpha wrote: post #15

Earlier quoted context omitted.

The specific EAST reactor [1] mentioned in the article is a testbed that will enable new technologies to be used on the ITER project. The ITER project [2] is currently the largest fusion power research project underway (and the largest reactor under construction). ITER's goal is to provide research that enables new technologies to be used on the DEMO project. The DEMO project's goal [3] is to provide commercially ava…

but 2033 is only 15 years away, not 20

I think calling 2033 highly unlikely would be an understatement.

https://en.wikipedia.org/wiki/ITER: ”Initial plasma experiments are scheduled to begin in 2025, with full deuterium–tritium fusion experiments starting in 2035.”

So, according to Wikipedia, DEMO will build on ITER’s results, but will produce energy before ITER’s first real fusion experiment starts.

Re: Chinese Tokamak reaches over 100M degrees

#52

Post by oldgradstudent »

kungtotte wrote: post #34
docker_up wrote: post #11

Stories like this scare me. With all of the precautions, even things like Fukushima failed and will poison our ocean for millennia. What happens if we have a runaway fusion process through some pathway that was unexpected? With all the talk about the LHC possibly producing mini blackholes or magnetic monopoles that could potentially cause protons to decay spontaneously, I don't have enough nuclear physics background…

The earthquake was the most powerful to ever hit Japan and the fourth most powerful in the world since modern record keeping began, and the investigation into the disaster showed that the safety precautions weren't adequate in the first place. You can't dismiss the technology based on that incident. Just like we don't ban cars because a lot of people don't operate them properly.

When I was in high school we visited a small 5MW nuclear reactor. It was a few years after Chernobyl and we got a very long lecture about how this was all the fault of the terrible Soviet design and that it could never happen in a western-designed nuclear reactor.

As far as I remember from the news at the time, the tsunami was terrible, but not unprecedented. If this obvious risk was ignored, what other risks are being ignored elsewhere?

Re: Chinese Tokamak reaches over 100M degrees

#53

Post by zaarn »

NamTaf wrote: post #13
rococode wrote: post #7

Earlier quoted context omitted.

You seem to know what you're talking about - do you know what the end goal of the work in this field is? Is it working towards nuclear fusion as an energy source?

Sustainable high-temperature plasma is what we need to create fusion as an energy source. Current fusion processes rely on pulsing a very short instant of high temperature. This creates a brief instance of fusion, but takes heaps more energy than that quick moment of fusion releases. Thus, it's a net negative of energy. One way to do this that the US uses for nuclear weapons research is to zap a small bit of gas with…

ITER will never produce electric energy but they plan to achieve Q=5, ie, output 5 times more energy than put in.

The more important work on ITER is work around enabling actual power stations using Q=5 and developing the tech to maintain operating fusion reactors (remote robots, etc.)

Re: Chinese Tokamak reaches over 100M degrees

#54

Post by aaaaaaaaaab »

Cthulhu_ wrote: post #46
aaaaaaaaaab wrote: post #39

Earlier quoted context omitted.

What... no. Igniting fusion is easy. Keeping the plasma confined is the hard part due to its immense heat.

Easy or relatively easy? They still need to pump in enough energy to get it up to a 10 million degree (if not more) temperature.

Fusion can be made in your living room: https://en.m.wikipedia.org/wiki/Fusor

Re: Chinese Tokamak reaches over 100M degrees

#55

Post by garmaine »

thaumasiotes wrote: post #40
NamTaf wrote: post #8

Earlier quoted context omitted.

As I understand, this represents sufficient energy to overcome the Coulomb Barrier [1] which naturally repels atoms apart. To cause fusion, you need to push particles together either hard enough or fast enough that they push through this repulsion and fuse. The repulsion is a product of the electrostatic repulsion of the positive charges of the nuclei (pushing the positive ends of two magnets together, essentially).…

> you need to push particles together either hard enough or fast enough that they push through this repulsion What's the difference between "hard" and "fast"? What does pushing "hard" mean?

GP isn't using standard terminology, but I would presume "hard" was in reference to more mass, which results in higher kinetic energy at lower temperatures.

Re: Chinese Tokamak reaches over 100M degrees

#56

Post by zaarn »

docker_up wrote: post #11

Stories like this scare me. With all of the precautions, even things like Fukushima failed and will poison our ocean for millennia. What happens if we have a runaway fusion process through some pathway that was unexpected? With all the talk about the LHC possibly producing mini blackholes or magnetic monopoles that could potentially cause protons to decay spontaneously, I don't have enough nuclear physics background…

Fusion processes cannot go "runaway" (unless you manage to recreate an entire star in the lab by accident, which requires a lot more mass than we have).

If a fusion reactor is breached, the plasma will likely dump it's thermal energy into the air (likely this will cause a minor detonation, it's strength depends on the energy in the reactor and the amount of fuel). Additionally it'll leak some short lived isotopes and maybe create a few long live ones.

All in all, a detonated fusion reactor is likely save to walk in the same year it exploded, if not significantly earlier.

Re: Chinese Tokamak reaches over 100M degrees

#57

Post by donkeyd »

txcwpalpha wrote: post #15
rococode wrote: post #7

Earlier quoted context omitted.

You seem to know what you're talking about - do you know what the end goal of the work in this field is? Is it working towards nuclear fusion as an energy source?

The specific EAST reactor [1] mentioned in the article is a testbed that will enable new technologies to be used on the ITER project. The ITER project [2] is currently the largest fusion power research project underway (and the largest reactor under construction). ITER's goal is to provide research that enables new technologies to be used on the DEMO project. The DEMO project's goal [3] is to provide commercially ava…

Any idea on how much money we're spending on this?

Also, I can imagine it's a joint project only partially because we can share the cost, I imagine another reason to work together is so that no one country gets this technology first.

Re: Chinese Tokamak reaches over 100M degrees

#58

Post by red75prime »

Cthulhu_ wrote: post #49
red75prime wrote: post #43

Earlier quoted context omitted.

> poison our ocean for millennia On global scale it negligibly increased ever-present background radiation. It's not a good thing, but far from poisoning.

Wasn't said ever-present background radiation only a thing after the nuclear bomb tests? I read a while ago that steel from old ships that sunk deep is highly valuable because it's not irradiated yet.

It is low-backgroud steel([0]), not no-backbround steel. Potassium-40, for example, is a naturally occurring radioisotope. See Banana equivalent dose ([1]).

[0]: https://en.wikipedia.org/wiki/Low-background_steel

[1]: https://en.wikipedia.org/wiki/Banana_equivalent_dose

Re: Chinese Tokamak reaches over 100M degrees

#59

Post by mirekrusin »

hoffs wrote: post #33
adtac wrote: post #32

Once we achieve sustainable fusion, will it be possible to "share" the energy with everyone else to create more independent fusions? Kinda like keeping the candle burning so as to light more candles because matches are too costly. Now, I don't expect politics to allow sharing of fusion energy to help other countries.

Isn't fusion reactor basically infinite energy, I mean sure it makes total sense to no share it with other because you can sell your free energy for cash, but considering that a lot of global scientists work on it and most of the findings are published, don't think that such strategy would last long.

Not really, it will wear out due to radiation so you need to change the body periodically, unless you use other fuel like helium-3, but it's got it's own problems - much higher fusion temperature and very rare on our planet (a lot of it on the surface of the moon though, it would be worth mining if we had working reactors).

Re: Chinese Tokamak reaches over 100M degrees

#60

Post by Symbiote »

donkeyd wrote: post #57
txcwpalpha wrote: post #15

Earlier quoted context omitted.

The specific EAST reactor [1] mentioned in the article is a testbed that will enable new technologies to be used on the ITER project. The ITER project [2] is currently the largest fusion power research project underway (and the largest reactor under construction). ITER's goal is to provide research that enables new technologies to be used on the DEMO project. The DEMO project's goal [3] is to provide commercially ava…

Any idea on how much money we're spending on this? Also, I can imagine it's a joint project only partially because we can share the cost, I imagine another reason to work together is so that no one country gets this technology first.

Several billions of Euros, with Europe paying the largest share, but the reactor is in France so we get much of the secondary benefit (i.e. scientists and engineers spending their salaries there, construction work).

http://www.iter.org/faq (several are relevant).

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