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How To Line a Thermonuclear Reactor
sciencehabit writes "One of the biggest question marks hanging over the ITER fusion reactor project — a giant international collaboration currently under construction in France — is over what material to use for coating its interior wall. After all, the reactor has to withstand temperatures of 100,000C and an intense particle bombardment. Researchers have now answered that question by refitting the current world's largest fusion device, the Joint European Torus (JET) near Oxford, U.K., with a lining akin to the one planned for ITER. JET's new 'ITER-like wall,' a combination of tungsten and beryllium, is eroding more slowly (PDF) and retaining less of the fuel than the lining used on earlier fusion reactors, the team reports."
This is known as the "first wall" problem in fusion reactors. It's good to hear there's been progress.
It's discouraging to hear how slow progress is on ITER.
Solar is orders of magnitude simpler in technological complexity, but economic return on solar is just starting to happen. Not because of the technology, simply because population is growing and the cheaper black shit is running out.
Same thing with Fusion. Technologically, we have enough engineers and scientists in the world to make it a world-scale Apollo type endeavour and get Fusion to market by 2020-2030.... if we wanted to. But honestly, the economy doesn't want to. Not until it runs out of whatever is cheaper.
With the heath issues around using beryllium, that will be inconvenience. Preparing alloys of W and Be are likely to be expensive for the quantities need too. Melting W takes a lot of heat, fabricating it is hard, if you are machining it with Be you have the heath issue from the finds. Doing it all by PM leads back to the heath issue.Well maybe we can get it fabricated in China or India.
The Space Shuttles TPS tiles are some amazing material... though even they are only spec'ed to maybe 1500C, but what is facinating about them, to me, is that they don't hold heat. They can be seared to 1200C and seconds later will be cool. So maybe a system that uses this technology combined with an extra liquid-based fast heat-removal system?
What material can withstand 100,000C ??? How do we test that?
The Admin and the Engineer
Its a little like the old puzzle "What do you use to hold an acid that can eat anything?" Difficult, but interesting, problem.
Python: 'And then suddenly you have a language which says "we're all stuck with whatever the whiniest coder wants".'
If this is the alternative, I say we start developing rare earth mining in this country ASAP.
Have gnu, will travel.
how long will it last with homer at the controls?
Thorium is better, it's clearly doable, much safer, and it's incredibly abundant.
It's not supposed to work economically, experiments are like that.
Troll harder next time.
Where are these temperatures of 100,000 C ? - Tungsten BOILS at 5660 C and Beryllium at 2970 C - Of course, that's at 1 atmosphere pressure. Something doesn't seem right to me unless the 100K is a good ways away from the walls or the pressure inside is incredibly high (doubtful).
Magnetic fields contain the plasma. That heat never reaches the walls.
I think the pressure inside is low, and the temperature is the temperature of the (low pressure) plasma. So think a smallish number of ions at really high velocity.
From what I understand, the plamsa is confined by a magnetic field, but not perfectly. So, when some plasma ions go astray, they've gotta hit a material that can take high temperature. The beryllium is probably converted into some useful atom by a nuclear process when this happens.
I might be really wrong about this, but it's my best guess.
I've been working at PPPL this summer, and that's the latest idea
Had to google, that and learned something! It appears biodiesel is at the very bottom of the EROEI list: per this Wikipedia chart. How it's produced will have to change dramatically for it to become economically viable to meet current demand. The only emerging technology that seems to have that potential is algae, in some form or another. Of course it will be another decade at least before those technologies can scale to even begin to meet some demand, so it's still unproven at this point.
Twenty years ago I was a program officer at the Office of Fusion Energy, US Department of Energy. The ITER planning had started. My take -- there is no way on Earth that a tokamak can be cost competitive. Even if it works, even if the first wall problem is solved as may be indicated above, the engineering costs are so prohibitive as to price the whole concept out of consideration.
I earlier worked on Trisops, a simpler fusion concept that might be economically feasible, but I even doubt that. In the official fusion community, which is fixated on the the tokamak, it suffered from the NIH ( Not Invented Here ) syndrome and was defunded.
In descriptive linguistics, grammaticality has been supplanted by acceptability a long time ago.
Ezekiel 23:20
Company B sells solar panels.
Both companies provide products for the electrical generation market.
One company provides the resource, and another provides a conversion technology and not the resource itself.
Both companies are expecting exponential demand growth in the electrical generation market. Company A's resource is limited and finite. Once it's used up, it's done.
Company B's conversion technology allows an unlimited resource to be tapped.
At some point, Company A's finite resource will cost too much in overhead to keep prices low.
Company B's conversion technology will offer a cost competitive advantage to Company A's energy source.
Company A will panic, drop prices and ramp up production. Their existing customers will hold on, but eye Company B's product as a backup.
Because Company B's conversion technology only gets better with R&D cash from new sales. They ramp up production and features (efficiency), again becoming cheaper than Company A.
Company A really panics, pulls from savings and drops their price further, providing the customers who absolutely require Company A's resource.
By now, the market has realized Company B's business strategy is more sound. They aren't selling a finite resource, they're selling a widget that converts an inexhaustible resource into electricity. Therefore it's company overhead isn't bound by finite laws, but simply how efficient it's manufacturing is. It's a gadget manufacturer, not an energy supplier.
Unless you got a better theory than Einstein and can prove it, you've proven your ignorance.
There may be limits on how materials are used today, but that's what R&D is all about.
New, more effective ways of doing things with existing resources/technology.
Technologically, we have enough engineers and scientists in the world to make it a world-scale Apollo type endeavour and get Fusion to market by 2020-2030
Bullshit. They've been at it for 30-40 years and still haven't broken Q 1, where Q is the ratio between power inputted and power generated. You need a ratio of 5:1 just to sustain the plasma. 10:1 is needed for power production. The best verifiable results have been Q=.75.
You can't claim a problem is solvable just by throwing enough money at it.
Please help metamoderate.
Don't forget Dr. Bussard's Polywell concept.
It's under a publishing blackout because it's a project currently being funded by the Navy, but the fact that it's still being funded is encouraging.
If you run a 60watt laptop all day but then ride your bike to work you'll be using far less energy than someone who commutes 60 miles and never touches a computer.
It's also not hypocritical to be resentful of your only good options. If the people in power only are willing to offer you a bad option then you can simultaneously use that *bad* option while also resenting them.
I HATED my old cable company. 200ms pings. 1mbps internet and extortionist prices. But you know what my other alternative was? Dial up. I could wish the people running my cable company would go to jail or something so that something would take their place while still using the best of the worst options available to me. Since then they have been bought out 3 times and now are great!
There is a natural monopoly in energy. It's a monopoly formed by the billions and trillions of dollars necessary to compete. If it was an area I could do something about I would definitely put my money into a 'good' and ecologically sound option--but the option isn't available to everyone. I actually can pay a premium to my energy company and get 100% carbon free energy. I'm sure the electrons reaching me are from natural gas but I'm paying for the higher cost wind turbines and solar elsewhere.
It's only hypocritical to complain about your options when you have a good option that you're not utilizing. We can sit on our high horse and demand that our leaders create policies which force good options to be made available while forcing those who cause damage to the public sphere to pay for the true cost of their product.
From what I understand, the plamsa is confined by a magnetic field, but not perfectly. So, when some plasma ions go astray, they've gotta hit a material that can take high temperature. The beryllium is probably converted into some useful atom by a nuclear process when this happens.
The process creates plasma, which should be chemically destructive. Beryllium and tungsten sound like usual suspects for such an application.
The nuclear part comes from the nuclear reaction - it produces neutrons aka the worst type of radiation. This will transmute elements, and is hard to block. It's better blocked by light elements so Beryllium might have been picked due to that too. I'd guess the mentioned elements transform into something (relatively) benign, since the experts wouldn't pick something that transforms wholesale into Strontium-90.
I'm not a physicist either so any experts are welcome to correct me too!
https://en.wikipedia.org/wiki/Migma
"I don't which is worse, that everyone has a price, or that the price is always so low"--Hobbes