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China Just Made a Major Breakthrough In Nuclear Fusion Research (techienews.co.uk)
New submitter TechnoidNash writes: China announced last week a major breakthrough in the realm of nuclear fusion research. The Chinese Experimental Advanced Superconducting Tokamak (EAST), was able to heat hydrogen gas to a temperature of near 50 million degrees Celsius for an unprecedented 102 seconds. While this is nowhere near the hottest temperature that has ever been achieved in nuclear fusion research (that distinction belongs to the Large Hadron Collider which reached 4 trillion degrees Celsius), it is the longest amount of time one has been maintained.
The goal of nuclear fusion research is to produce clean, renewable energy. It seeks to do this by replicating the same conditions that power the sun.
Clean is misleading here - the public's idea of "clean" does not line up with any known fusion reaction that we can hope to achieve. They're all going to produce radioactive waste, just less so (and generally less nasty stuff) than fission reactors. But we need to get around the same stigma that has hamstrung fission reactors - that "radioactive" means "cancerous death" to the electorate.
... good god, no. Never. No one for a thousand years to come will ever seriously think about trying to smush two protons together hard enough for them to fuse without a sun-sized gravity well to assist with it. It takes an incredible amount of time for any two hydrogen atoms to fuse in the sun, on the order of millions of years.
Replicating the same conditions that power the sun
I realize that journalists need to summarize their stories, but fusion is a topic that is already understood more-poorly-than-normal by most people. They need to not be making people think about Spiderman 2.
Wikipedia has two great articles (go figure, the good ones are outside of election coverage topics) I would recommend:
https://en.wikipedia.org/wiki/...
https://en.wikipedia.org/wiki/...
Also, it would seem that I misremembered the half-life of a proton in our Sun's core. It's a billion years; my millions of years is wrongish.
It takes billions (not millions) of years for hydrogen atoms to fuse in the sun - that is precisely why the sun has a billions-of-years lifetime. So in building a fusion reactor, we need many orders of magnitude higher reaction rates, and to achieve them at many orders of magnitude lower densities. One way of doing this is to have much higher temperatures. The solar core temperature is about 15 million degrees and TFA has 50 million degrees for this new result, and 80 million degrees for half a second at a European reactor. This sounds unimpressive, but the reaction rates are very sensitive to temperature - proportional to about T^8 as I recall, but I didn't quickly find an online reference for this. 75 million degrees would therefore give a boost of about 5^8 which is about 400,000.
In the sun, the first reaction in the chain (proton+proton->deuterium) is the rate limiting step. In a reactor, we can provide deuterium enriched fuel and bypass this step. I don't know what the reaction rates are, but I suspect that this will be a greater benefit that the higher temperatures. You can do even better with tritium in the fuel, but your reactor becomes an intense neutron source, leading to induced radioactivity in nearby materials. Some proposed designs use these neutrons to breed more tritium from a lithium blanket around the reactor. (Once I get beyond the proton-proton chain reaction, I'm just relying on pop-science knowledge, so corrections from the more knowledgeable are welcome.)
Stars a bit more massive than the sun burn hydrogen via the CNO cycle, which has even higher temperature dependence (from memory, about T^17). I've never heard of anyone suggesting using the CNO cycle in a fusion reactor - presumably there are good reasons, but I don't know what they are. One problem is you need to wait for radioactive decays, but these have half-lives on the order of 1 to 2 minutes, and a commercial reactor would be running for much longer than that.
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
https://www.lenr-forum.com/forum/index.php/Attachment/386-IEEE-brief-DeChiaro-9-2015-pdf
Dear reader, I quit reading this document as soon as I saw convicted fraudster and scam artist Andrea Rossi cited by it unironically -- as you should as well.
Hot fusion is also going nowhere until anuetronic fusion becomes practical (pro tip: it's quite a bit harder to do) because the fast neutrons eventually destroy every known material used as the plasma-facing "first" wall. That's something the ITER fanboys are not telling you (for obvious reasons).
"Politicians and diapers must be changed often, and for the same reason."
The LHC experiments concern high-energy particle physics, not fusion research. It is operating at energy scales well above plasma [unless you want to talk about "quark-gluon plasma, which is something else entirely] and at conditions which have nothing to do with nuclear fusion.
Here is why it's not the USA - scroll down to the graph for the very quick answer:
http://hardware.slashdot.org/s...
China is also dumping US 1960's-style money in to scientific research and development. Of the three major space-faring countries, China, Russia, and the USA, you'll note that only China and Russian currently have manned spaceflight programs.
China has also built the largest ground recieving dish in the world, out-doing the one in Puerto Rico by a factor of almost two.
China is rocking the 1960s American Science Research meme so hard it hurts.
Meanwhile, American politicians are arguing about whether or not climate change is real, and we slot somewhere between countries like Latvia and Lithuania in Science globally. Hong Kong, (china), Singapore, and Japan are #1,2,3 globally, if you were curious.
moox. for a new generation.
The german stellerator Wendelstein 7-X aims for up to 30 minutes of confinement. At the moment only a some very earlier tests have been done, that did not aim for long confinement but just to check that everything is okay with the installation. Wendelstein 7-X started operating end of last year and EAST started operating in 2006.
This chinese tokamak aims for confinement of up to 1000s and has reached 102 seconds of confinement after 10 years. At the end of 2013 they already had reached 30 seconds. Wendelstein 7-X will first do some experiments that do not aim for a really long confinement time, only up to 10 seconds. These experiments are planned to last about 2 years, after that they will install some additional equipment, that is planned to take 15 month. The chinese record should thus last for at least 3-4 years. But news from Wendelstein 7-x have been very positive, I would not be surprised if confinement works extremely well.
Jan
Um... the US spends more money on R&D than any other country, and more money per person than any other country except Israel and South Korea.
https://en.wikipedia.org/wiki/...
Flint is an issue with switching from a good water system to a more acidic and known polluted one to save a few bucks. That's coupled with STOPPING procedures which helped prevent lead-leeching/corrosion in pipes, DENYING the issue despite people with rashes, hair loss, and other extreme symptoms, and then VICTIM BLAMING and COVER UPS (hey, it's better, we tested it... in homes that have already added filters) when many cases started to surface. At the same time people and their children were being poisoned by lead - and the gov't was denying it - they added extra water coolers of nice clean water in the offices of those same government officials.
But hey, keep telling yourself how bad other countries are, and how yours is so much better. When the "best country in the world" is also a polluted, dry desert rock with a bunch of sick jobless people you can pat yourselves on the back that China is so much worse.
The first step to addressing a problem is to stop denying it exists. Part of that means you start to realize that "but hey... look over there" is a method to distract from the problems "over here"
Those numbers are highly misleading. The NIH gets about 32 billion, the NSF about 5-6 and NASA gets a few billion. That's ~10% of the research money account for on the Wiki link you post. Most of the money accounted for there is for defense, like the DoD--not for basic research. There's no doubt that China spends a lot here too, but you'd have to eliminate defense funds to make a better apples-to-apples comparison.
I'm a Professor in the US, and I have many colleagues in the hard sciences in China. China and the Middle East are spending a lot more money on basic research now, per researcher, than the US.
You seem to not be aware that fusion research is an open and collaborative project between all nations. We share data, equipment, tokamak run-time, and scientists. Your partisan suspicion is understandable for someone not in the know, but it's totally wrong. The fusion scientific community is well aware of what is going on at EAST (and all other major collaborative facilities), when the machine turns on, when it turns off, when there is a leak, when a diagnostic malfunctions, and when things go well.
At DIII-D (USA), we have built a "remote control room" for EAST and KSTAR so that researchers in US can operate EAST on the third shift when our colleagues in China are sleeping. Control parameters will be transferred to Hefei over the internet and diagnostics will be fed back to the monitors in almost real time.
BTW, I am a fusion research scientist based in US, but I do do some work on EAST as well as other machines.