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How To Line a Thermonuclear Reactor

Soulskill posted about a year ago | from the very-carefully dept.

Power 184

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."

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184 comments

The Best Lining (0)

Jeremiah Cornelius (137) | about a year ago | (#41037151)

Is composed of the bodies of energy ministers and power-generating companies.

Re:The Best Lining (1)

Anonymous Coward | about a year ago | (#41037741)

Indeed, who needs people to run power companies, anyway, man? Energy should be free, man~

Re:The Best Lining (0, Flamebait)

egamma (572162) | about a year ago | (#41038151)

Is composed of the bodies of energy ministers and power-generating companies.

As opposed to slashdot users who are all high and mighty, posting on their energy-using computer that was produced in a factory that is probably not powered by a water wheel, all the while sitting in the basement of their mom's energy-cooled house?

Re:The Best Lining (0)

Anonymous Coward | about a year ago | (#41038417)

AC without AC reporting in

A better first wall (5, Informative)

Animats (122034) | about a year ago | (#41037161)

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 (5, Insightful)

Bananatree3 (872975) | about a year ago | (#41037189)

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.

Re:Solar (1)

Anonymous Coward | about a year ago | (#41037297)

You do realize most oil producing countries are on track to produce more oil then any previous year with greater known dril-lable reserves in the ground then at any other point in time???? So it's going to run out really fucking soon... like when we stop finding oil everywhere???? I am not saying burning oil doesn't have problems but the cost of the resource is not going to be one of them for a long time. Oh, I do will have my money where my mouth is am pretty close to shorting oil futures but it wouldn't surprise me to see the price continue up for another couple of months before finial topping off and falling like a stone. Of course that assumes that Iran won't try anything stupid. we'll see.

Re:Solar (4, Insightful)

doublebackslash (702979) | about a year ago | (#41037375)

Bananatree3 likely wasn't being ignorant, but rather stating the situation simply. The economics are driven by... economics. Just because they know where more is and are getting at it faster does not mean that it is the cheap stuff that used to spring out of the ground and soak the plains of Texas and Texans alike. This oil is deeper, dirtier, and more spread out.

We are really good at getting at oil, because we need it for every piece of modern life, or at least it is the only feasible way to do it. So we get the oil, however we can.

It would have been more accurate to say, "the CHEAP shit is running out". Other than that I think it is a fine comment.

Re:Solar (0)

Anonymous Coward | about a year ago | (#41037501)

Actually, there is still a lot of cheap shit in developed countries but nobody wants to see more oil platforms so we are drilling up the expensive shit first, you know because god forbid some rich dude has see an oil platform...

Re:Solar (1)

Bananatree3 (872975) | about a year ago | (#41037617)

You know in a few decades, the Manna from Terra will no-longer be cost effective? Economically there might be plenty of short-term profits to be had, but only a fool would use that kind of thinking for long term planning...

Re:Solar (4, Insightful)

bmo (77928) | about a year ago | (#41037987)

forbid some rich dude has see an oil platform...

Fucking this. God forbid they see a fucking windmill. I live here in the Northeast and the fucking Cape Wind project should have been finished 5 years ago (I may be exaggerating) but for the fucking douchebags on Nantucket being butthurt seeing windmills on the horizon TEN FUCKING MILES AWAY.

We could have a combination of wind, solar, tide, and nuclear weaning our asses off of the middle-eastern oil, but no, NIMBYism abounds. So we continue to get our asses mired in the middle east, where politics is not just a social structure, but a full contact sport with no rules and every day being a grudge match over slights done 1500 years ago.

We're fucking masochists wanting to be a part of that. We must be. No other explanation make sense.

--
BMO

Re:Solar (4, Insightful)

Bananatree3 (872975) | about a year ago | (#41037403)

You're missing the point. I was really pointing at all Fossil Fuels too.

We'll switch over to alternative fuels long before we run out of Fossil Fuels, simply because they'll be cheaper to produce. A gallon of bio-diesel be cheaper per gallon than petrol diesel at some point, Solar will be cheaper per KWh than burning coal at some point. When that happens, the entire economy will flock over to these alternatives because of price benefits. There will probably be some economic swings as oil/gas/coal producers try to keep competitive, but they're prices will eventually be too high to compete against alternatives.

It's classic supply and demand. When exponential demand meets a finite resource, prices go up. All the alternative fuels are also finite (only so much KWh of sun can be extracted, for example) but they are also renewable. Fossil fuels don't.

grammar (1)

Bananatree3 (872975) | about a year ago | (#41037477)

BTW, my grammar in my above comment sucks I know lol

Re:grammar (0)

Anonymous Coward | about a year ago | (#41038437)

Really, your grammar doesn't look so bad. The only errors I see is your talking about kelvin watt hours (kilowatt hours would be kWh) and your capitalization of fossil fuels. I'm not sure that either one counts as a grammatical error.

Re:Solar (0)

Anonymous Coward | about a year ago | (#41037587)

As Amory Lovins puts it [youtube.com]: "Oil is becoming uncompetitive at low price before it becomes unavailable at high price."

Re:Solar (2)

marcosdumay (620877) | about a year ago | (#41038015)

A gallon of bio-diesel be cheaper per gallon than petrol diesel at some point, Solar will be cheaper per KWh than burning coal at some point.

That's not such a simple certainty. It's very likely that solar will get cheaper than coal at some point, but the judge is still out on biodiesel.

There is a feedback loop hidden there, dumped by the EROEI of those sources.

EROEI (2)

Bananatree3 (872975) | about a year ago | (#41038087)

Had to google, that and learned something! It appears biodiesel is at the very bottom of the EROEI list: per this Wikipedia chart. [wikipedia.org] 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.

Re:Solar (0)

Anonymous Coward | about a year ago | (#41038037)

"When that happens, the entire economy will flock
over to these alternatives because of price benefits." ... which will reduce demand for fossil fuel and reduce its price.

Alternative will never replace fossil fuels. It's classic supply and demand that even you should understand.

Economics 101 (2)

Bananatree3 (872975) | about a year ago | (#41038295)

Company A mines coal.
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.

Re:Economics 101 (0)

Anonymous Coward | about a year ago | (#41038483)

Finite doesn't mean "small" or "soon". The sun is also a finite resource because it will run out eventually, it's just that it is going to take so long that we don't care about that. Coal and oil won't run out anytime soon, so economically it doesn't matter any time soon that they are not renewable - just like it doesn't matter any time soon that solar isn't renewable. Indeed, the laws of thermodynamics state that there cannot exist a renewable energy source of any kind. What you are saying will happen eventually, yes, but not any time soon and certainly not soon enough to be much of any help with our current CO2 issues.

Re:Economics 101 (1)

Bananatree3 (872975) | about a year ago | (#41038679)

The factor isn't just a matter of resources, but also emotional markets.

Let's say a solar panel system on my house will cost 5 years to pay itself. Let's say it will output >80% of its original rating for 20 years.

If I take out a 5 year loan with minimal interest to pay for the solar panel system, all I'm paying for is the interest in the end. The next 15 years give me a net zero electric bill at least and possibly a net profit.

As a consumer that's a helluva deal. One option gives me a guaranteed cost for 20 years. The other option is to fork cash over for the next 20 years.

Assuming the above economics, solar provides a 400% profit over the next 20 years.

The funny thing is, this isn't that far off, and renewable energy conversion technologies are only getting cheaper.

Re:Solar (2)

I_am_Jack (1116205) | about a year ago | (#41038359)

Alternative will never replace fossil fuels. It's classic supply and demand that even you should understand.

Alternative energies will never replace fossil fossil fuels, right up until the moment they do, and then they will. That's a simple enough example of how a planet of a fixed size will always have finite limits on mineral resources that I'm sure you should be able to understand.

Re:Solar (0)

Anonymous Coward | about a year ago | (#41038445)

You are right, but the consequences are not what you think. Once there is enough demand for energy, the price of fossil fuels will rise higher and higher until they meet the price of alternatives and at that point the fossil fuel price will stay there as people move to the alternatives. However, this still means that the fossil fuels will be used to 100% capacity - it's just the spillover that goes to alternatives. What really needs to happen to decrease use of fossil fuels is for production of fossil fuels to decline either because we exhaust fossil fuels or because the production costs of alternatives go below the production costs of fossil fuels. That might happen eventually, but I doubt that "evenutally" is going to be any time soon - maybe in 50 years.

Re:Solar (1)

Bananatree3 (872975) | about a year ago | (#41038545)

What really needs to happen to decrease use of fossil fuels is for production of fossil fuels to decline either because we exhaust fossil fuels or because the production costs of alternatives go below the production costs of fossil fuels. That might happen eventually, but I doubt that "evenutally" is going to be any time soon - maybe in 50 years.

I think you're underestimating the ingenuity of the alternative energy sector manufacturers. They're producing a conversion technology rather than producing the resource themselves. They give their customers much more than energy, they give their customers some intangible quality that fossil fuel makers can only dream of:

  • A sense of independence - customers can generate more energy independent of external supply.
  • One cost - Houses are bought with mortgages, and even if alternative energy converters (solar/wind/etc) are expensive up front they have a guaranteed output/failure rate (like MTBF for harddrives). Coal/oil/natural gas prices are speculated on commodities markets. If a customer has a cost-competitive choice between a guaranteed energy cost over 20 years or having to pray and hope with fossil fuels, they'll invariably take the guaranteed offer.

    Companies like Apple sell products not just on technological features, but intangible features like "coolness" or "ease of use". "energy independence" and "guaranteed cost" are intangible but factor heavily in one's purchase.

Re:Solar (0)

Anonymous Coward | about a year ago | (#41037315)

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....

It's nice to know that physical limits no longer play any roll in determining what technologies can be developed. When we want faster than light travel enough, i'm sure we'll be able to do it.

Re:Solar (1)

Bananatree3 (872975) | about a year ago | (#41037531)

Light speed? Who knows.

High temperature linings inside a fusion reactor? Just put together a mammoth, well ran, flush-with-cash R&D program and see some company somewhere invent the breakthrough. If the issue is just finding the right alloy, molecular structure, etc. etc. it simply comes down to how big your R&D and engineering programs are.

Re:Solar (-1)

Anonymous Coward | about a year ago | (#41038283)

"Light speed? Who knows. "

That statement alone invalidates your opinion on pretty much everything. Sorry, you're in my loony bin now.

Re:Solar (0)

Anonymous Coward | about a year ago | (#41037661)

Oooohh, what kind of roll? I'm in the mood for a nice cinnamon roll with plenty of icing, you know, for physics!

Re:Solar (0)

Anonymous Coward | about a year ago | (#41038103)

We already know that there are no physical reasons why fusion power can't become a practical option. There are plenty of engineering reasons, though, and those are the expensive ones.

Re:Solar (0)

Anonymous Coward | about a year ago | (#41038135)

" There are plenty of engineering reasons"

Such as the physical limits of real materials...

New ways of thinking (2)

Bananatree3 (872975) | about a year ago | (#41038397)

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.

Re:Solar (0)

Anonymous Coward | about a year ago | (#41037321)

Too bad solar together with pretty much all other renewable energy sources utterly suck for providing baseline energy load. Though solar in itself is pretty decent, it's only problem is storage for when Sun isn't shining (enough). Transportation over long distance is another relatively costy thing.

In short-ish term I'd like to see thorium rectors, in a bit longer and possibly not actually quite workable thing would be alternative way of doing fusion in form of Polywell.

Re:Solar (1)

Bananatree3 (872975) | about a year ago | (#41037581)

The reason they utterly suck is because their short-term, large-scale economic viability has been almost nonexistent. It's a waiting game to see when fossil fuels become expensive enough that heavy re-development of these alternatives will make sense. The closer we get to that price curve intersection, the more R&D companies will spend to make alternatives suck less.

Re:Solar (0)

Anonymous Coward | about a year ago | (#41037749)

The reason they utterly suck is because their short-term, large-scale economic viability has been almost nonexistent.

Not really. They suck because we have no working energy storing mechanism that would be good enough for storing entire nation's energy for the night, not to mention a few weeks that would be needed for replacing fossil fuels.

It's not economics, it's physics. Though at least in theory there could be ways of providing that storage mechanism. Creating hydrocarbons or H2 would be one, though extremely wasteful way of doing it.

Re:Solar (0)

Anonymous Coward | about a year ago | (#41038071)

actually i believe capacitive batteries/ultra-capacitors are close to horizon, they would solve this issue

Re:Solar (1)

Anonymous Coward | about a year ago | (#41038159)

I think you might be underestimating the insane amounts of energy that is being used at all times. Going by wikipedia US alone was using a bit under 30PWh of various energy sources per year in 2006. Per day that is around 3.5TW/h of energy. That's the equivalent of about 80 billion ipad2 batteries, not including losses.

How much more efficient are those capacitive batteries/ultracapacitors per volume/weight/cost than regular li-ion batteries? It would take improvement in orders of at least a few thousands to make it work in the scale required.

Re:Solar (0)

Anonymous Coward | about a year ago | (#41038523)

Their efficiency is currently about equal but the fact you can dump charge an ultracapacitor without expensive control circuits makes them appealing

THORIUM (3, Insightful)

sanman2 (928866) | about a year ago | (#41037595)

Thorium is better, it's clearly doable, much safer, and it's incredibly abundant.

Re:THORIUM (1)

Anonymous Coward | about a year ago | (#41037743)

For nuclear power, not lining reactor walls.

I cannot conceive of how Thorium would be even a remotely safe material to line a fusion reactor with.

Re:THORIUM (0)

sanman2 (928866) | about a year ago | (#41037985)

I thought the whole point of a fusion reactor is nuclear power, and not just to make something whose walls you want to line.

Re:THORIUM (1)

benjfowler (239527) | about a year ago | (#41038583)

The reactors have to run hot and efficiently enough to heat up the walls and blanket, where the heat is pumped away to drive a turbine.

The plasma is trapped using incredibly powerful magnetic fields, but there are points in the reactor where hot particles come near the wall (e.g. the divertor region). This is required to pump out waste helium and other impurities to keep the reaction running.

Re:THORIUM (4, Interesting)

benjfowler (239527) | about a year ago | (#41038561)

Thorium is very heavy. This is a bad thing.

For a tokamak first wall, you want a very tough, lightweight material. Something with very few electrons to strip off when it inevitably contaminates the plasma. If you use heavy elements, loads of energy is wasted ionizing the contaminants, and the energy is radiated away.

They're using beryllium, which is a very lightweight metal, doesn't retain expensive fuel, but toxic six ways to Sunday. It melts at a low temperature, but the operators of JET have installed elaborate safety systems to prevent as much as possible, damage to the first wall.

For the divertor (the 'exhaust pipe'), they use tungsten: heavy, but has the highest melting point of any known material, and there are few worries about contamination of the plasma, where the plasma edge ('scrape off layer') contacts a physical surface inside the reactor.

These are way better than the old material: carbon composites; which are incredibly tough and don't melt or sputter easily, but trap fuel away from the plasma.

Re:Solar (1)

Panaflex (13191) | about a year ago | (#41037667)

AKAIK - nowhere at any time has ANY scientist shown ANY meaningful energy return on hot fusion research. ITER is the biggest failure of ideas I've ever seen.

Seriously, that money could be spent on beer and pizza.

Oil will be gone far sooner than expected - the strategic national stockpile or beer and pizza is not enough to sustain an energy-free economy. Beer and pizza won't just be for Sunday football No, we're going to need all those calories once the economy swings back to human power!

Q problems by an order of magnitude (2)

SuperBanana (662181) | about a year ago | (#41038563)

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.

correction (1)

SuperBanana (662181) | about a year ago | (#41038655)

Research on tokamacks started in the 50's. They've been at it for 62 years, and they still can't solve a number of problems, including the fact that the high energy electrons generated tear the machine apart. Nevermind the fact that large parts of the machine become (effectively) permanently radioactive.

Beryllium, that's inconvenience (2)

AbrasiveCat (999190) | about a year ago | (#41037277)

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.

Re:Beryllium, that's inconvenience (2)

fuzzyfuzzyfungus (1223518) | about a year ago | (#41037365)

I'm told that children just can't resist the sweet taste of beryllium salts. They seem like logical candidates, if we can train them sufficiently in the necessary machining techniques.

Re:Beryllium, that's inconvenience (1)

zrbyte (1666979) | about a year ago | (#41037677)

It's probably done by robots.

Re:Beryllium, that's inconvenience (1)

benjfowler (239527) | about a year ago | (#41038609)

Fuck, don't let them hear you call the remote handling equipment 'robots'. I made that mistake, and the scientist showing me around got fair up me for it. It's 'remote handling', not 'robotics', apparently.

Re:Beryllium, that's inconvenience (1)

benjfowler (239527) | about a year ago | (#41038597)

I've seen the facilities they use at CCFE Culham to make and refurbish beryllium components. It's all remotely operated.

Re:Beryllium, that's inconvenience (1)

fa2k (881632) | about a year ago | (#41038687)

It's not inconcievable to use beryllium. The detectors at LHC have beam pipes made of beryllium. These are the vessels which separate the vacuum in which the particles travel from the detectors. ITER is a scientific institution of similar magnitude.

My first thought... shuttle tiles (2)

catmistake (814204) | about a year ago | (#41037293)

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?

Re:My first thought... shuttle tiles (0)

Anonymous Coward | about a year ago | (#41037325)

What material can withstand 100,000C ??? How do we test that?

In fusion reactors.

Re:My first thought... shuttle tiles (1)

Anonymous Coward | about a year ago | (#41037395)

It's not just the temperature. They need a wall material that does erode impurities in to the plasma. Any impurities will radiate the heat away and cool down the plasma.

Re:My first thought... shuttle tiles (1)

Anonymous Coward | about a year ago | (#41037443)

The tiles weren't cool in seconds. They were such amazing insulators that you could pick them up by the corners and not get burned because they wouldn't transfer any significant amount of heat, thus calling them insulators.

Re:My first thought... shuttle tiles (5, Funny)

mrbester (200927) | about a year ago | (#41037607)

What material can withstand 100,000C ???

The pastry wrapping a McDonalds Apple Pie.

Re:My first thought... shuttle tiles (4, Interesting)

mako1138 (837520) | about a year ago | (#41037807)

Space-age materials are pretty amazing, but Fusion-age materials are at a whole different level. I think the community hasn't expressed to the public just how daunting the challenges are. Controlling the plasma is one thing, but engineering the plasma-facing components (PFCs) is a whole 'nother kettle of fish.

The so-called "first wall" is the interior layer of the fusion reactor. It has to stand up to neutron bombardment, but it also has to avoid shedding particles into the plasma. For example high-Z materials such as tungsten, molybdenum, and vanadium are interesting for their neutron tolerance, but if atoms scrape off into the fusion plasma they will radiate like crazy (proportional to Z^2) and drain a lot of energy out of the plasma. That's why they are testing a Be coating (Z=4).

On the other hand, you have divertors, which sit in direct contact with the plasma and basically hold it in place so it doesn't randomly hit the wall. These have to withstand a high heat load. I admittedly don't know much about divertors so I will stop there.

There's also the superconducting material in the coils of the tokamak to consider. Of course there's a whole bunch of neutrons flying around. But also but it turns out that a lot of the issues with superconducting magnets are mechanical in nature. The HEP community has figured out how to build SC magnets consistently, but I think the magnets needed for a tokamak are quite different.

There is supposed to be a International Fusion Material Irradiation Facility, part of the ITER project (and basically a consolation prize to Japan), that will provide intense neutron beams for materials studies. But I am not really sure what the situation/timeline is for that given the funding problems ITER has faced.

Re:My first thought... shuttle tiles (0)

Anonymous Coward | about a year ago | (#41037819)

Don't confuse temperature & heat.

Re:My first thought... shuttle tiles (4, Interesting)

elfprince13 (1521333) | about a year ago | (#41037859)

The problem isn't the temperature alone, it's also that heavy atoms will pollute the plasma if they come loose at all. The Princeton Plasma Physics Laboratory is working on a liquid-lithium walled reactor to try and handle several of these problems. Check out LTX (Lithium Tokamak Experiment) [pppl.gov].

Re:My first thought... shuttle tiles (2)

benjfowler (239527) | about a year ago | (#41038619)

Yeah, carbon fibre composites.

They were using carbon tiles in JET until fairly recently too. They have some big advantages (tough as hell), but serious disadvantages too (retails fuel and contaminants).

"the current world's" (0)

Anonymous Coward | about a year ago | (#41037311)

"The current world's largest"? You're telling me we know of larger ones on other worlds?

Basically readability is, I know, something /. editors seem not to care for these days, but such obvious glaring issues surely need fixed. "The world's current largest" is the grammatically accurate English language way to describe it.

I'm now desperately hoping I have not made any such grammatical error myself, which is why I'm posting as an AC.

Interesting (3, Interesting)

interval1066 (668936) | about a year ago | (#41037329)

Its a little like the old puzzle "What do you use to hold an acid that can eat anything?" Difficult, but interesting, problem.

Re:Interesting (1)

gmanterry (1141623) | about a year ago | (#41037421)

Its a little like the old puzzle "What do you use to hold an acid that can eat anything?" Difficult, but interesting, problem.

I always wondered about that too. I remember being taught about the scientific search for the 'Universal Solvent'. Why didn't these people realized that they were dealing with an impossible subject? As far as I can determine fire is the closest thing to the Universal Solvent.

Re:Interesting (0)

Anonymous Coward | about a year ago | (#41037811)

I always wondered about that too. I remember being taught about the scientific search for the 'Universal Solvent'. Why didn't these people realized that they were dealing with an impossible subject? As far as I can determine fire is the closest thing to the Universal Solvent.

Technically that is water. No one said it had to dissolve /quickly/ or completely.

Re:Interesting (0)

Anonymous Coward | about a year ago | (#41037827)

Its a little like the old puzzle "What do you use to hold an acid that can eat anything?" Difficult, but interesting, problem.

I always wondered about that too. I remember being taught about the scientific search for the 'Universal Solvent'. Why didn't these people realized that they were dealing with an impossible subject? As far as I can determine fire is the closest thing to the Universal Solvent.

Nope... would you believe the Universal Solvent actually plain ol' water.

Re:Interesting (0)

Anonymous Coward | about a year ago | (#41037777)

Its a little like the old puzzle "What do you use to hold an acid that can eat anything?" Difficult, but interesting, problem.

idk but I think it's probably an interdisciplinary problem. I'd ask an expert in xenobiology, like Lt. Ellen Ripley.

Re:Interesting (1)

K. S. Kyosuke (729550) | about a year ago | (#41038267)

Its a little like the old puzzle "What do you use to hold an acid that can eat anything?" Difficult, but interesting, problem.

Microgravity and surface tension?

Re:Interesting (0)

Anonymous Coward | about a year ago | (#41038467)

You don't. Simple as that.

Instead keep it in a field. Electromagnetism, laser, or even gravity, will do the job.

In related news ... (2)

PPH (736903) | about a year ago | (#41037339)

... insurgents in West Africa take control of tungsten and beryllium mines pillaging and burning villages in their path. It is expected that their profits related to the fusion reactor market will sustain inter-tribal conflicts for generations to come.

If this [youtube.com] is the alternative, I say we start developing rare earth mining in this country ASAP.

Re:In related news ... (0)

Anonymous Coward | about a year ago | (#41037705)

The main obstacle to REE mining in the USA is thorium. Because thorium is typically found together with REEs, and because it is (slightly) radioactive, this makes REE mining prohibitively expensive in the USA. Whatever thorium comes out of your mine along with the REEs has to be treated as "nuclear waste," which is why there is very little REE mining activity in the States these days.

Google around on "thorium reactor" or "LFTR" and you'll see why it would be a "win-win" for us to reclassify thorium. It would simultaneously free up REE mining and allow easier development of 4th-gen nuclear reactors.

Re:In related news ... (1)

PPH (736903) | about a year ago | (#41038501)

Whatever thorium comes out of your mine along with the REEs has to be treated as "nuclear waste,"

And again we'll have to deal with the sobbing hippie factor. Someone should tell them that since it [wikipedia.org] is a naturally occurring radioactive element, it must be good for you. Just like everything else in the natural products store (like hemp).

Seriously, folks. Get over the "nuclear waste" histrionics. The technology to handle this stuff exists and it can be secured without too much trouble. Or, better yet, consumed in a reactor.

how long will it last with homer at the contols? (3, Funny)

Joe_Dragon (2206452) | about a year ago | (#41037369)

how long will it last with homer at the controls?

Re:how long will it last with homer at the contols (0)

Anonymous Coward | about a year ago | (#41038095)

The real problem is once homer screws it up where are we going to get a replacement beryllium sphere?

Fraudsters (-1, Troll)

Anonymous Coward | about a year ago | (#41037583)

ITER is a huge fraud, a disgusting waste of taxpayers' money, and will NEVER work economically, if it in fact ever DOES work. The so-called 'scientists' working on it are just on a gravy train for life, they get paid no matter how badly they perform. What a ridiculous farce it is.

Re:Fraudsters (5, Insightful)

Anonymous Coward | about a year ago | (#41037725)

It's not supposed to work economically, experiments are like that.
Troll harder next time.

Re:Fraudsters (1)

endinyal (2700219) | about a year ago | (#41037925)

You're absolutely right. We also should never have sent people to the moon. What a waste of money that was. Not like anything ever came out of that right? Computers, satellites, GPS, your cell phone, etc.. Go back into your hole...

Re:Fraudsters (-1)

Anonymous Coward | about a year ago | (#41038481)

Are you claiming that we didn't have computers and satellites before the moon shots? Are you claiming there's some kind of connection between test pilots playing golf on the moon and GPS? Can you trace that out for me? What exactly didn't exist before and that only could have come from walking on the moon?

Seems to me computers were well on their way BEFORE we went to the Moon... [youtube.com]

You know, they used wheels on the lunar rover, are you saying we wouldn't have wheels if it wasn't for NASA? Learn some history of technology and some facts, you're making a fool of yourself.

Huh? (1)

Zomalaja (1324199) | about a year ago | (#41037739)

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).

Re:Huh? (2, Informative)

Anonymous Coward | about a year ago | (#41037823)

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.

Re:Huh? (2, Informative)

Anonymous Coward | about a year ago | (#41037855)

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 know what (0)

Anonymous Coward | about a year ago | (#41037853)

I'd use wet toilet paper myself.

Underground? (0)

Anonymous Coward | about a year ago | (#41037955)

Why not just build the reactor underground? Huge amounts of mass to sink the escaping energy if containment is lost. Good reuse for the LHC maybe?

Re:Underground? (1)

Anonymous Coward | about a year ago | (#41038175)

If containment is lost it's hardly a problem. For one thing there's very little fuel in the reactor and for another it stops producing energy the moment the magnets lose power, in contrast to fission reactors.

There is no way a tokamak can be cost competitive (5, Interesting)

InterGuru (50986) | about a year ago | (#41038171)

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 [wikipedia.org], 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.

The unsolved problem isnt the wall but disruptions (1)

stooo (2202012) | about a year ago | (#41038411)

The critical problem is the power of the disruptions in the machine, which will be strong enough to destroy the machine quickly.
These disruptions can't be avoided and are a flaw of tokamaks which is becoming a problem at this scale.

The wall being made of beryllium will also be a problem, together with the tritium in the chamber will make this thing extremely dangerous. If this thing releases materials after damage due to disruptions, we will not really be able to clean the mess.

Re:The unsolved problem isnt the wall but disrupti (1)

ModelX (182441) | about a year ago | (#41038689)

I listened to a talk by someone doing materials research for the first wall. Apparently disruption of the plasma is not the big problem, what they are doing is optimizing the whole process of producing, running, cleaning and recycling the first wall tiles. They are testing different materials by bombarding them with neutrons, then they are trying to separate the nasty stuff and recycle what's useful.

They're doing it wrong. (0)

Anonymous Coward | about a year ago | (#41038603)

They should feed the power generated back into the magnetic containment field and thus the stronger the energy produced, the stronger the containment field.

Make it a feedback circuit.

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