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Bill Gates To Help China Build Traveling Wave Nuclear Reactor
First time accepted submitter BabaChazz writes "Microsoft Corp. co-founder Bill Gates says he is in discussions with China to jointly develop a new kind of nuclear reactor. During a talk at China's Ministry of Science & Technology Wednesday, the billionaire said: 'The idea is to be very low cost, very safe and generate very little waste.' Gates backs Washington-based TerraPower, which is developing a nuclear reactor that can run on depleted uranium."
Just wait, China !
Bill Gate will give you Blue Screen of Nuclear Death !!
Muchas Gracias, Señor Edward Snowden !
Too bad he's prohibited from doing something like this in the US. If it weren't for ill-rational fears of nuclear power the R&D would be done in the US.
"Ubuntu" -- an African word, meaning "Slackware is too hard for me". - stolen from Dan C alt.os.linux.slackware
China is one of the largest CO2 polluters in the world. Traveling wave reactors are known to be incredibly clean and safe. If you give the Chinese abundant safe and clean energy, this is going to really help the global warming problem.
The reason traveling wave reactors were never used, even though the technology has been know for half a century, is that they produce no waste that is useful to making nuclear weapons. That is only reason why all nuclear power nations wanted the more dangerous reactors that ran on uranium and plutonium fission.
But modernizing the safer, non-weaponizable form of nuclear power is a great way to go.
>> There is no problem with Thorium
Wrong. There are many, many problems with thorium.
To begin with, this substance is more chemically and radiologically toxic than Pu. So having it molten 24/365 inside corroding tubes is pure suicide for a whole land.
aaaaaaa
In Japan they no longer have the honor they once had in their leadership so the responsible ones do not kill themselves anymore
I call bullshit.
Are you seriously going to sit there and tell me that suicide is the honorable response to a fuck-up?
The fuck it is. The honorable response to a fuck-up is devoting your life to cleaning it up, until either you fix it or you die of natural causes.
Suicide is a coward's way out, it passes the problem to the next guy and somehow through the power of death magically absolves you of your sin.
I needed a sig so people would know who I am, but I was too drunk to make something witty, so you get this instead.
This sort of tech has been pushed and rejected by most of the western world due to fear mongering and morons that can only think of japan or chernobyl when they hear the phrase nuclear power. Sadly China get a jump to clean and safe energy because the rest of the world panda to the irrational morons in society, on the whole though at least this reduces the worlds Coal burning.
China will use it to build and charge batteries that will be sold in Wal-Marts in the US, so this is a win-win, right . . . ? An the "traveling nuclear waves" stay in China . . . ? Isn't a traveling nuclear wave called a tsunami, and caused a disaster in Japan . . . ?
Actually the title sounds like fear mongering (Bill/China/Nukes) or a bad joke:
"So, Bill Gates walks into a bar in China with a traveling nuclear wave reactor, and the bartender says . . .
[Insert Your Ask Slashdot Punchline Here]
Can you surf nuclear waves . . . ? Maybe China wants to take over the surfing travel industry . . . ?!
This topic always attracts lots of emotion, with very little substance . . . oh, and I guess I'm an offender, too . . .
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
this substance is more chemically and radiologically toxic than Pu
Do you guys just make this stuff up as you go along? The half life of natural Thorium is 1.405×10^10 years. Radioactivity is the inverse of half life. (By contrast, the half life of Pu-239 is ~24,000 years, and the Iodine-125 they inject you with when you get an MRI has a half life of 59 days.)
The ultimate question for all reactors is what they leave behind.
They can't help leaving behind fission products (that's where they get their energy from), which isn't too much of a problem, as it takes only about 300 years for them to decay to levels of radiotoxicity of natural uranium in equilibrium with its decay products.They will leave behind some Uranium, but this can still be used in other reactors.
The problem is mainly residual Plutonium, Americium and other elements, with half-lives of several thousand or tens of thousands of years, which require hundreds of thousands of years to decay to such levels. (Because of the very damaging high energy alpha decay, rather than lower energy and much less damaging beta and gamma decays.)
On the one hand non-fissle transuranic elements capture neutrons and interfere with the chain reaction, on the other hand capturing neutrons either splits them or eventually transmutes them into fissle elements. This turns them into fission products, which we can handle with reasonable confidence. The question now is: does the travelling wave in the travelling wave reactor provide enough neutrons to transmute and split the transuranic elements it breeds, such that the reactor as a whole reaches a stable equilibrium before the end of its operating time? Conventional reactors don't, because the chain reaction is stopped for lack of neutrons long before a stable equilibrium is achieved. Most breeder reactors do, but it depends a lot on how tight the neutron economy of the particular reactor is. And afaik (correct me if you know better or have access to specifications), the neutron economy of the travelling wave reactor is rather tight and might well be possible, that the wave leaves ever more transuranics in its wake as it moves, without ever reaching an equilibrium over the whole of the reactor.
Why is reaching a stable equilibrium before the end of operation enough? In this case you can add some additional transuranics at the start of operation and still reach the same equilibrium at the end of operation. If the amount you can add at the start (and still reach equilibrium) is larger than the amount left at the end of operation, you effectively reduced the total amount. Given that, you effectively solved the long-term problem of transuranic waste, by limiting its amount and eventually burning it.
The question is, can the travelling wave reactor do that or not? (There are other options ex post, but it is always best to not let the problem exist in the first place rather than dealing with it later.)
Wait till you see the meltdown!
First: Say it with me. Nuclear reactors ARE NOT nuclear bombs.
Unless you're dealing with highly enriched materials with proper reflectors and shape (these things REALLY matter) you're generally not going to get any sort of supercriticality, not to mention setting off a nuclear explosion isn't something that you can do just by accident. Even a simple device like 'Little Boy' requires some extreme engineering. A multistage device with a megaton yield....by accident? Not gonna happen... this pesky thing called physics will get in the way.
Second: We don't care about using unenriched uranium. That's a good thing to use as enriched uranium is incredibly dangerous to make (Bing uranium hexafloride), and dealing with weapons-grade anything is always dangerous.
Third:
Traveling wave reactors are fairly hands off deals. Most other reactors require constant attention to maintain their "balance" and if intimate knowledge of the system (along with piss poor planning and bad control rod design) is lacking then you can end up with situations like Chernobyl. If your DR plan doesn't account for a completely passive cooling system, as in Fukushima, or a dark plant... again see Fukushima.
"Chinese Amazons, power armor, laser swords.... things just meant to be." - Shampoo, A Very Scary Bet
In the new design, the reactions all take place near the reactor's center instead of starting at one end and moving to the other. To start, uranium 235 fuel rods are arranged in the center of the reactor. Surrounding these rods are ones made up of uranium 238. As the nuclear reactions proceed, the uranium 238 rods closest to the core are the first to be converted into plutonium, which is then used up in fission reactions that produce yet more plutonium in nearby fuel rods. As the innermost fuel rods are used up, they're taken out of the center using a remote-controlled mechanical device and moved to the periphery of the reactor. The remaining uranium 238 rods—including those that were close enough to the center that some of the uranium has been converted to plutonium—are then shuffled toward the center to take the place of the spent fuel.
Currently there is no known material that could be used to encase the fuel rods in -- they need to survive radiation exposure for decades without expanding.
Suicide is not a coward's way out. Yes, it passes the buck, but what needs to happen in someone's head which allows them to go against every instinct every living thing has had for billions of years - survival - has to be pretty god-damned tough to go through.
Don't judge until you try it yourself.
Thorium itself is not a nuclear fuel, it's what is called a fertile material. When bombarded with neutrons it produces Uranium-233 , which is an excellent nuclear fuel, and most certainly usable in a nuclear weapon. The process is very similar to how Plutonium-239 can be made by bombarding Uranium-238 with neutrons.
The main reason people don't use Thorium and U-233 for making bombs is that the U-233 tends to become contaminated with highly radioactive isotopes, making it difficult to handle. In principle you can avoid this by using a more elaborate irradiation and separation technique, but it's just easier to use Uranium-bred Plutonium instead.
To summarise:
Thorium-232 and Uranium-238 are not on their own useful for nuclear fuel or weapons. However, they can be turned into fissile material by bombarding them with neutrons.
In this way Th-232 can be turned into U-233
Whereas U-238 can be turned into Pu-239.
Both U-233 and Pu-239 can be used for weapons, but it is easier to keep the radioactivity of the Pu-239 low.
Hence it is easier ( and cheaper ), to use Uranium fuelled reactors to make a bomb than to use Thorium.
... so that least they're doing something right.
Yes. They made sure that their coast line is shielded by an island in front of it, which breaks any incoming tsunamis...
The travelling wave reactor concept appears to be basically a sodium cooled reactor that has a lot of extra U-238 , allowing it to go very long without refuelling as the enriched portion of the core "travels" along the U-238 ( this image explains the concept: http://evworld.com/press/IV_twr_concept.jpg ).
I have to say I am sceptical. The main economic issue with sodium cooled fast breeders is that they are very capital intensive due to the challenges of handling flammable sodium. Thus trading even more capital investment ( in the form of a larger core ) for less frequent refuelling seems like a bad idea. Furthermore, any design that is to see widespread deployment should make use of economics of scale. Fuel fabrication, reprocessing and so on can be centralised, with a few facilities potentially serving many reactors, or even multiple nations. It thus makes little sense to move capital costs towards the power plant and reactor, away from facilities that can be centralised. This is why I doubt all the talk about "Integral" facilities or on-line reprocessing ( as suggested for molten salt reactors ).
It's not very hard to build a breeder with a 2-3 year core lifetime anyway, and you probably don't want to run it much longer than that without shutting it down for servicing, repairs, inspection and so on.
Don't get me wrong. It's a cool idea technologically. I just don't think it will be economically competitive with other Gen-IV designs. The focus for breeders today should be on reducing capital up-front investment, improved safety and reliability. No utility is going to invest billions up-front in an experimental design that is unlikely to be economically competitive with other alternatives.
>> Radioactivity is the inverse of half life
Radioactivity is not the same as toxicity.
Th232 decays emitting alpha radiation, which makes it safe to handle with gloves, but will assure you cancer if inhaled.
Furthermore, the most dangerous stuff are the fission products.
aaaaaaa
of actual decommissioned nuclear power plants. If such a list exists, it would be microscopic in comparison to the list of aging plants given a rubber stamp extension on life just so the owners never have to foot the bill or more accurately not until they bailout with their golden parachutes. This may be more of a US problem, given that corporations are firmly in control of government.
Bill Gates invests in more nuclear power. Google invests in solar power plants.
Here's Bill Gates' TED presentation on this project from almost 2 years ago:
http://www.ted.com/talks/bill_gates.html
Even if half of this design works out as advertised, i think this would be awesome! Pity that the 'western world' wasn't interested in investing in it and trying it out....
And why is it not as good as plutonium or depleted uranium?
Please do not read this sig. Thank you.
ALL nuclear reactors DO have a proliferation risk in them. The main driver of the proliferation risk is they create and spread knowledge about how to safely and effectively work with highly radioactive materials. Some designs are worse than others in that the materials and of processing equipment can be directly re-purposed for weapons. With that said, the main reasons nuclear is dead in the US is, #1 Given its history, who is dumb enough to trust a multi-billion dollar investment to the regulatory whims of the NRC? Answer: No one with a billion dollars. #2, There are too many people who earn a living scaring people about nuclear power. Ralph Nader essentially retired on it. NIMBY is just a tactic they use.
I hope solar and wind eventually pay-off because Hydro and Nuke are dead in the U.S.