Biggest Obstacle of Nuclear Fusion Overcome? 444
Yetihehe writes "Nuclear fusion could become a more viable energy solution with the discovery of way to prevent super-hot gases from causing damage within reactors. The potential solution, tested at an experimental reactor in San Diego, US, could make the next generation of fusion reactors more efficient, saving hundreds of millions of euros a year."
Re:hmmm.. (Score:2, Interesting)
Like with space travel.
Vapourwear (Score:4, Interesting)
From TFA
"I think it's a very interesting solution to a very important problem," says William Dorlund, a plasma physicist at the University of Maryland in College Park, US. But he warns it will be difficult to apply the solution to functional reactors until the theory behind the technique is well understood.
Translation:- Vapourwear
Re:biggest obstacle will be environmentalist. (Score:5, Interesting)
Fission, on the other hand.. is problematic. It might be the only viable alternative at the moment (well actually I'm just saying that to not get flamed) but nobody can say it doesn't have its share of problems. Waste being the biggest, safety (yeah yeah I know, pebble reactors, yada yada
Viable is a key word (Score:3, Interesting)
Nuclear fusion could become a more viable energy solution
This is what mankind needs to be sustainable, a cheap and clean energy source. Lets face it, we are adicted to energy and burning all that oil and natural gas is not sustainable. Plus it is costing a fortune. So hopefully they can find more solutions like this and put this technology to widespread use. 5 cent a KWH anyone?
Re:biggest obstacle will be environmentalist. (Score:2, Interesting)
Well, occasionally perhaps, when you run in to someone who understands the distinction. It seems that every time I bring fusion up, it has to be explained that it is not fission. A lot of people hear the word "nuclear" and just immediately get worried. This is why the term NMR ("nuclear magnetic resonance") had to drop the word "nuclear" to establish the MRI ("magnetic resonance imaging"). The word "nuclear" wasn't marketable.
crap! (Score:5, Interesting)
Fission also produces neutrons.
Since both reactions produce neutrons they have the same issues - namely dealing with radioactive wastes.
Fisson is easy to create. A team of boy scouts can do it in their own back yard. Fusion is very difficult.
Fission can be totally safe. It can also be very dangerous. It depends on the reactor design but the issue is that the technology is already on the shelf. IE. We can do it now and we have been able to do it for 50 years.
Now the issue is that with the USA designed high pressure reactors, they only use about 2/10 of 1% of the uranium that is mined. What this means is that with a better design we can get about 475 times the milage from our uranium.
There is so much energy available to us that it is almost beyond our imagination. Consider that there are about 114 reactors in the USA which have been running say about 50 years. 50x475 = 23,750 years. There has literally already been enough uranium mined for almost 24,000 years for a well designed reactor like the IRF (Integral fast reactor - look it up in the wikipedia). If we wish to produce 100% of our energy from uranium we have enough uranium mined already for over 2,000 years. Of course the best solution is to use this energy to free up hydrogen which we can combine with carbon to produce synthetic oil (syncrude!). We need about 75 GWe reactors right now here in Alberta. We have a terrible hydrogen shortage. The price of gasoline at the pumps is a symptom of this problem.
Yet - we keep reading stories about the holly grail - Nuclear Fusion.
Yes, some day will will build a fusion reactor. The research is a good idea. But the idea that it will be problem free is a false idea. The biggest obstacle is not wear and tear due to plasma - the biggest obstacle is neutrons flying around and these are difficult to control. In fact - the best solution might be to pack a bunch of thorium around the plasma and use the neutrons to transmute it into U233 which we can cart off to a fission reactor. As an alternative we can pack U238 around the plasma and cart of the Pu239. These are viable fuel cycles - unfortunately at present they are not politically correct.
Re:I just want a Mr. Fusion in my car (Score:3, Interesting)
But what you can't gain energy doing is 56Fe + 56Fe -> 112Te
So you always have to have something lighter than iron as part of your fuel if you want to gain energy.
and i thought ... (Score:2, Interesting)
So, politics rather than brains is dictating the speed of advance in this field.
Re:1:1.2784 (Score:3, Interesting)
Re:crap! (Score:5, Interesting)
Fusion produces orders of magnitude more neutrons.
In a fission plant, excess neutrons are bad. You want the pile to be barely critical, a stable, but not runaway, chain reaction. So you actually don't have a lot of neutrons flying out of the pile. You moderate the ones you do produce, and use them to fission additional fuel atoms.
But in a D-T fusion scheme, the bulk of the liberated energy is produced in the form of a very energetic 14 megaelectron-volt neutron. And this neutron doesn't participate in additional reactions, DT fusion isn't a chain-reaction process like fission is. The neutron will leave the plasma. Heck, ideally, that's how you get energy out of the reactor, by trapping that neutron in a surrounding blanket, causing that blanket to heat up so you can use that heat to boil water. Every single D-T fusion generates one of these neutrons, so the neutron flux will be many many times that of a fission plant.
But that's not an issue because of "radioactive waste." The wastes we're concerned about from fission aren't neutrons, they're from fission fragments and decay daughters. Some of those might emit neutrons themselves, but really, that's not the primary concern; neutron-induced radioactivity is actually pretty short-lived.
The reasons neutrons are a concern in a fusion plant is that continuous high-energy neutron bombardment does very bad things to all known materials that you might want to build a reactor vessel out of. When a neutron strikes an atom, it displaces it within the crystal lattice. If that happens once, no big deal, but in a commercial fusion reactor, the reactor vessel will experience 300 to 500 displacements per atom over the lifetime of the device. That means that, right now, we don't even know what to build one of these things out of. Austinitic steels start to swell, crack, and degrade after only about 30dpa, and the very best candidate materials we know of can only handle about 150; those might be acceptable, if the cost of changing the inner wall out isn't too high, but we just don't know.
And ITER won't even begin to explore those issues. ITER's flux will only generate 3 displacements per atom.
Fusion is very very hard. My money says that we'll never use commercial fusion power.
Obstacle? (Score:2, Interesting)
Re:I just want a Mr. Fusion in my car (Score:3, Interesting)
Actually, the isotope with the highest binding energy per nucleon is nickel-62. You can look it up. [kaeri.re.kr]
I'd paste in a nice table that I just made, except the lameness filter won't let me.
But anyway, the isotope of Nickel with the highest binding energy per nucleon, using figures from the linked table, is Ni-62 at (8.794497 +- 2.3e-05) MeV.
For Iron, it is Fe-58 at (8.792144 +- 2.4e-05) MeV.
By way of comparison, the most abundant isotope of Nickel is Ni-58, at 68% abundance according to Wikipedia.
Ni-58 has binding energy per nucleon of (8.731963 +- 2.5e-05) MeV.
As for Iron, viz. Fe-56 (at 92%), with (8.790248 +- 2.4e-05) MeV.
Anyway, binding energy is very important but it is certainly not the only thing which determines what isotopes get produced most often.
Why this REALLY is big news (Score:2, Interesting)
The ELM's are effectively "bubbles" of plasma that "impacts" the wall. This leads to erosion of the wall
and significent heat loss. First, the plasma cools from the contact. Second, the wall erodes and atoms,
beinging significently heavier, never really get up to temperature. Third and most important, the atoms
from the wall cause brumstrumalung(sp) radiation. Each of these is a major energy loss and principle
reasons why fusion has never really worked.
Re:Biggest obstacle? (Score:3, Interesting)
Solar and wind are approaching economic viability as supplemental energy sources. What I mean is that they are good at helping meet some of the peak demand, but not so good as a baseline power source, since the wind doesn't always blow and the sun doesn't always shine. In particular, there are several hours each day in which the entire continent is in the dark (wind is also usually calmer at night). In an all-solar/wind energy scenario, you'd also need an enormous amount of energy storage capability (electricity-to-hydrogen-to-electricity in fuel cells, maybe), which rather dramatically raises your costs.
Nuclear, on the other hand, can be more expensive, but are well suited to be run continuously (aside from maintenance every once in a while), since fuel is only a small fraction of the cost per kW/h.
What makes more sense than either source on its own is nuclear fission to supply most of the baseline power, with solar and wind to supply peak power, and a few natural-gas fired plants for backup. Conveniently, peak generating times of solar and wind tend to correspond to peak demand.
Given the above scenario, you'll run out of fuel for your fission reactors in half a century or so (give or take a few decades), unless you start using breeder reactors, which aren't really a widescale-proven technology, and pose some nuclear proliferation issues. If you're going to pour research money into breeder reactors, why not spend it instead on fusion, which is pretty much the ultimate terrestrial power source?
Biggest problem? (Score:2, Interesting)
Re:1:1.2784 (Score:2, Interesting)
Gold retains its stable value according to *international* prices, as gold is more likely to be valuable to a larger number of people around the world than USD or Euro or any single currency. USD are worthless in some regions, because they are unable to be traded with local money marketers. Gold on the other hand, has no such limitation. Everyone, and I mean eveyrone, wants gold. So chnages in the price of gold are in actuality changes in the price of the major currencies used to measure it.
That is why, when measured in USD or Euro over the last few years it can appreciate significantly. Not because the value of gold is rising, but because the values of the currencies relative to *global* prices are falling. Strengthening major currencies like the Chinese Yuan, Indian Rupee and various middle eastern currencies could cause this, as could a strengthening South African Rand, South Africa being the largest supplier of gold currently.
You said that currencies like GBP, USD and Euro have proven to be a better store of wealth. That is because you are so used to measuring the value of dollars *in* dollars, that you will obviously perceive a dollar to always be stable to the dollar. Your GBP, USD and Euro are stable by tautology. To give you the extreme example, were the British government (or the US govt or any govt) to collapse, your currency notes would instantly be worthless. One ounce of gold today however, will get you roughly the same amount of food and shelter as it would have under the Roman empire 2,000 years ago. Try saying *that* about a $5 note in 2,000 years (ignoring the fact that a $5 note would probably be a rare collector's item by then).
There is a proposal by the Arab Leage to create the "Gold Dinar" which would be a common currency between Arab countries the same as the Euro is a common currency for European nations, with one important difference. Every dinar would be backed by a certain amount of gold. Anyone holding a dinar note would be eligible to go to the central bank and convert it into the set value of gold. The amount of gold a Gold Dinar would convert to would be fixed, and the central bank would only be able to print as many notes as they had gold in their vaults. Thus credit squeeze and liquidity crises would never happen, and money market manipulation would be impossible. Political stability aside, even if the entire country collapsed, the people's wealth in their earnings would be convertable to gold and retained unlike in Western countries where a government economic default means that ordinary every day people lose money.
As fiat currenies "create" fictitious wealth, leaving the real wealth in the hands of those that hold the economic assets (the corporate class of super-rich), a government collapse leave the peasants (you, me and Aunt Hilda) with nothing, and the super rich with everything, as they control the assets like the land, the bulidings, the gold and of course the military, while we're all left with our hands full of toilet paper and houses that defaulting banks are allowed to sieze to pay back their secured creditors who, again, are the super rich corporate types.
Wake up. Your dollars are nothing but paper.
- Naz