New Advances Bring Fusion Closer to Reality 785
An anonymous reader writes "The Christian Science Monitor reports on new advances in nuclear fusion research. For years we've been waiting for the technical breakthroughs that would make cost-effective fusion energy a reality. Are we getting close, or are the problems insurmountable?"
"Splitting atoms" (Score:3, Informative)
What I object to, though, is the insinuation that we are the ones splitting the nuclei of the radioactive elements. These things are radioactive precisely because of their tendency to decay and in fact split themselves. They don't even split into other elements. You can't turn uranium into gold, for example, even though it ought to be a straightforward process of splitting off the required number of protons from each atom (if the "we're splitting atoms" camp claims are correct).
We use the heat generated by the decay of radioactive elements to fuel our generators. We do nothing like smashing atoms into smaller bits.
Just a pet peeve of mine whenever I see a nuclear power article.
Re:Christian? (Score:3, Informative)
http://www.csmonitor.com/aboutus/about_the_monito
Re:Christian? (Score:1, Informative)
Re:Cheap? Clean? when will we learn (Score:5, Informative)
The plasma disperses and the fusion stops. What do you think happens when they shut the field down now after their tests?
"Wow, these are bad, very very very bad also."
Really? Why?
"The folks that came to our little burg for a 'rah rah' meeting claimed that power would be so cheap, it wouldn't be metered."
And it would have been had the anti-nuclear nutters who stopped the whole thing in its tracks. Yes 3 mile island happened and then chernobyl. So what? When an airliner crashes 400 people die. Do we stop all flight? Tens of thousands of people die in car crashes every year. Do we ban cars? No.
"The situation with nuclear power has not changed just becuase we are looking at 'new and improved' fusion"
If the halfwitted political loudmouths of society can be convinced this new form is "better" than the old form (whether it is or not) then we may get somewhere with it. If it ever works that is.
Why don't you read up... (Score:2, Informative)
My understanding is that it is one of the oldest and longest running *actual* news sources that has remained rather committed to the *actual* scientific truth, not the false truth pushed by Born Again Christian Fundamentalists.
Re:Christian? (Score:1, Informative)
Re:Years away (Score:1, Informative)
Re:"Splitting atoms" (Score:3, Informative)
I was having a discussion with my wife and several friends a few nights ago, and the topic turned to energy concerns. I was amazed to find that I was the only person in the room who wasn't opposed to nuclear power plants, but then I remembered that I was the only person in the room with an engineering background and anything more than a high school physics class under my belt. I showed them all this Wired article [wired.com] and it actually seems to have helped their understanding of how nuclear power can be safe. That's a hard concept to sell to almost anyone who's spent years being convinced, or convincing themselves, that nuclear power cannot be safe, but I've found that it is possible to convince some. I'm also very proud of my wife, who has abandoned her "They can build it, just not near our house" attitude.
Reason for Low Funding (Score:4, Informative)
With observations like that in reputable news sources like the Economist it is no wonder that investment in fusion waxes and wanes. People want a return on investment before the next election, not 30 years from now.
Re:Christian? (Score:4, Informative)
I'm sorry, we're looking at a theological magazine for technical articles?
I'm a total atheist, but the Christian Science Monitor is an extremely good publication, very independent.
It was apparently originally founded by a wealthy and religious woman about a century back. It is owned by a church, but you couldn't tell from the content. What you can tell is that it's not just another news organization for which profit is the all important thing.
Re:Atheism isn't the same as secularism. (Score:2, Informative)
There is such a thing as non-religious. And it has nothing to do with faith. Its called atheism.
Some useful links (Score:3, Informative)
http://www.jet.efda.org/pages/content/fusion2.htm
http://hyperphysics.phy-astr.gsu.edu/hbase/nucene
http://en.wikipedia.org/wiki/Timeline_of_nuclear_
http://www.fusion.org.uk/ [fusion.org.uk]
http://www.iter.org/ [iter.org]
Re:"Splitting atoms" (Score:3, Informative)
heh heh. Actually coal plants do produce radioactive waste. Instead of putting it in a container and storing it, they disperse it in the atmosphere.
Look at this link [epa.gov]
Notice that you get more than 3 times more dose if you live near a coal plant than if you live near a nuclear plant. (If you live within 50 miles of a nuke plant you get 0.009 mrem as opposed to 0.03 mrem if you live within 50 miles of a coal plant.)
Silicone Carbide? Fusion in breast implants? (Score:4, Informative)
Silicon and Silicone are often confused.
OTOH, perhaps this will be the next big thing. Talk about too hot to handle...
-j
Re:Ask Slashdot? (Score:4, Informative)
That isn't a problem any more. The EU decided a few weeks ago to build ITER in france by themselves and inviting the Japanese to join if they like (dont know what's happening with the US participation, but considering that they didn't join until a short while ago and wasn't paying much anyway it hardly matters)
Re:Cheap? Clean? when will we learn (Score:5, Informative)
This is not good for the retaining magnets - the magnetic field quenches, and the energy goes into heating up the magnets. Even the superconducting (and therefore cooled) ones warm up - boiling off a lot of refrigerant, and possibly/prbably distorting/damaging the coils..
Afer this event, th reactor was shut down for a long period (I think months), while the coils were checked for damage and realigned.
As for the amount of energy in the plasma itself - it's relatively small. Although the temperature is high, the particle density is actually quite low, so the total energy contained is (relatively) small. It *won't* go up like a hydrogen bomb.
The core lining in JET was lithium. It gets mildly radioactive due to being bombarded by neutrons all the time, but this is not a big deal. The neutron activation of the concrete and steel rebar used in the construction of the core (it has to withstand high mechanical forces from the magnetic fields) is more of an issue.
The plasma isn't meant to touch the tokamak wall, as it causes long and expensive downtime, but it's not as catastophic as (say) setting light to an oil well.
Re:The Law of Thermodynamics (Score:5, Informative)
Re:Years away (Score:2, Informative)
Re:Dumbed down (Score:1, Informative)
Re:Of course we will! (Score:3, Informative)
The CSM is actually a very respectable news source, and not especially influenced by CS ideology. It's no more about CS than The Economist is strictly about economics, or the New York Times is just about things that happen in New York.
Re:"Splitting atoms" (Score:3, Informative)
Since the day someone first burned coal. Coal has a uranium content of around 1ppm which is concentrated in the ashy residue after burning. It also contains measurable quantities of thorium, radon and radium. Coal ash can be as radioactive as an average granite (about 10-30 ppm uranium). If the powerplant doesn't have highly efficient filters then these tiny particles go up the smoke stack where they can be breathed in. Someone living downwind of a coal-fired power station accumulates about an additional 1% radiation exposure.
It's not a major problem (not compared to the acid and mercury thrown out by coal-fired plants), but fly ash from coal-fired power stations is widely used to improve concrete which may then get used in housing and offices. There people could be exposed to much larger amounts of radiation - particularly from the constant release of gaseous radon into their environment.
Best wishes,
Mike.
Re:"Splitting atoms" (Score:1, Informative)
"Radioactivity from burning coal" from Science News - October 1, 1994. W. Alex Gabbard, using EPA figures, found that, in 1982, U.S. coal burning power plants, which consumed 616 million tons of coal, released 801 tons of uranium and 1,971 tons of thorium into the environment, with roughly 11,371 pounds of the uranium as U-235."
From: http://cnts.wpi.edu/rsh/Docs/RADIOACTIVITY/Links2
Nuclear plants do not produce anything near 2,772 tons of radionucleides of 'ash' (burnt fuel) per year. Actual emissions are (ahem) somewhat less.
Re:science is as science does (Score:4, Informative)
"It's a real newspaper published by a church -- The First Church of Christ, Scientist in Boston, Mass., USA.... let's be clear: The Christian Science church doesn't publish news to propagate denominational doctrine; it provides news purely as a public service. Here's why: If the basic theology of that church says that what reaches and affects thought shapes experience, it follows that a newspaper would have significant impact on the lives of those who read it.
A newspaper whose motive is "to injure no man, but to bless all mankind," as its founder charged, would have a "leavening" effect on society, as well as on individual lives -- to use a metaphor Eddy herself appreciated and used. The idea is that the unblemished truth is freeing (as a fundamental human right); with it, citizens can make informed decisions and take intelligent action, for themselves and for society."
On a side note, I've just read throught the comments and I'm amazed at the number people that have made comments showing that they know no science... did IQs suddenly drop while I was away?
Re:"Splitting atoms" - yes, we do (I'm a Nuke) (Score:5, Informative)
While Uranium/Plutonium do decay naturally (stability of a nucleus is determined by the Nuclear Shell empirical formula, which is a rough analog of the electron shell theory - everybody wants to be Iron Fe/26, the most stable nucleus), there's another form of decay that's an outcome of genuine nucleus splitting. That's is the decay of of these usually-radioactive fragments. This decay is important to the operation of a fission reactor, but only in determining the criticality of a nuclear pile. 'Critical' == exactly as many neutrons are released in any time period as are absorbed, meaning steady power output. Basically, over 99% of the neutrons necessary to keep a steady level of fission events come from 'prompt' neutrons - neutrons that are freed in the splitting of an atomic nucleus. You get one small chunk (which could very well be gold), one big chunk, and a couple free/fast neutrons.
If these 'prompt' neutrons were enough to sustain criticality, then the number of fission events would increase geometrically. Since the time between generations is about a millionth of a section, this means that a reactor core that's 'prompt-critical' would quickly escalate in temperature until the structural integrity of the core failed, and you have a molten slag of Uranium - which is exactly what happened at Chernobyl.
So the way to avoid this, you have to put in neutron-absorbing control rods to keep the number of 'prompt' neutrons below the number necessary to sustain the next generation of fission events. If 'prompt' neutrons were the only neutron source, your nuclear reactor would quickly cool down. But the decay of the fragments (which are ususally radioactive isotopes of stable elements) release additional neutrons. The 'art' of tuning a nuclear reactor is to insert the control rods just enough so that the reactor isn't prompt-critical, but the decay neutrons are just barely enough to make the pile critical.
One of the biggest problems with fusion in general is fuel. The easiest fusion reaction is deuterium-tritium. Deuterium is plentiful - the ocean is full of 'heavy water' where one of the hydrogen atoms in a water molecule has a proton and a neutron. Tritium, however, is radioactive with a pretty short halflife. You have to make tritium by getting Lithium to absorb a neutron, then decay.
Last time I was up-to-date on fusion research, there was only an estimated 300 years of Lithium to sustain the predicted energy needs of the world. However, with fission fast-breeder reactors like they use in France, there would be 5000 estimated years of power. Fission fast-breeder reactors can be built today - it's just that to make them passively safe, you need to use a liquid metal coolant like sodium, and any disaster like Chernobyl (from terrorists, for example) would be catastrophic. Liquid sodium will explode if it gets wet, so it's a huge engineering challenge. Argonne Nat'l Labs has reactor designs like this, but the US population is scared of nuclear power plants (plus, the cost overruns at plants made them economically unfeasible).
[I am a published principal author and presentor of a fusion reactor design (presented at the 8th Topical Meeting on the Topic of Fusion Energy in Salt Lake City), so I have a tiny bit of credibility. I got out of the field specifically because of the 15-year carrot-on-a-stick paradox.]
Re:Step one - increase the cost of alternatives (Score:2, Informative)
It doesn't work that way. Fusion electricity isn't competing with other sources of electricity, it is competing with the price of running the plant. As it stands now, a controlled fusion reaction generally requires more power than it produces, a net energy loss. Simply increasing the price of other forms of electricity doens't magically make the efficiency of a fusion reactor climb above 0.
Why the guvvies haven't gotten fusion to work (Score:3, Informative)
Re:"Splitting atoms" (Score:4, Informative)
Take a look at some of the research and data on how much naturally radioactive particles are released into the atmosphere through burning of fossil fuels...
According to this Report to Congress on Wastes from the Combustion of Fossil Fuels [epa.gov], radioactivty in fossil fuels is not a problem.
The report says (page 44) that because the radioactive elements are not burned, they concentrate in the ash instead of spreading in atmosphere.
As for the danger of the ash, the report says:
The report concludes that the risks from non-radioactive elements in coal (selenium, arsenic, aluminum, and boron) are of much more concern.
Re:"Splitting atoms" (Score:5, Informative)
it produces very long lasting nuclear waste;
The longevity of some waste is important to consider, but there are three important mitigating factors that are usually overlooked in discussion.
First, longevity and intensity of nuclear waste are inversely related. The really nasty stuff has halflives of hours to days. The mid level stuff on the order of months. It's actually the low level waste that can last such a long time.
Secondly, reprocessing of the low level waste would extract useful plutonium that can be used as fuel again and will further reduce the volume of waste to store. It may even be possible to reduce the volume yet again by irradiating the low level waste to force it to decay faster.
Finally, coal burning releases a great deal of thorium and other radioactives. If coal plants were held to the same standards for release of radioactive waste products as nuclear plants are, each one would produce many tons of low level radioactive waste a year. That waste would also have to be stored for thousands of years.
Perhaps we should measure low-level waste in the unit "hours of coal", that is, in terms of the released radioactive waste per hour from an average coal fired power plant.
The real problem with nuclear power in the U.S. is lack of standardization in plant design and waste management. With standard design, we could build a body of practical operational and engineering knowledge that would apply to every plant. That in turn would allow increased safety.
lies, damn lies, etc... (Score:3, Informative)
Ah the wonders of a contextless statistic. Wow, America has spent more than $17 Billion on nuclear fusion in the last fifty years without producing a commercially viable reactor?! Damn those profligate scientists and their free-spending ways! We must put a stop to this before they bankrupt us!
Oh wait. $17 billion divided by 53 years is... $320 Million a year.
In Federal budgeting terms, $320,000,000 is LINE NOISE. It's more than the National Endowment for the Arts gets, but that's about the only thing I can think of that's smaller. In comparison, check out these fun numbers from Table S-3 of our current federal budget [akamaitech.net]:
Department of Defense: $401,000,000,000 (that's FOUR HUNDRED BILLION, and please note that that specifically doesn't include any money we are spending in Iraq)
Department of Homeland Security: $68,200,000,000
Department of Housing and Urban Development: $31,000,000,000
Executive Office of the President: $300,000,000
Yeah, you read that right: the "keep the White House bathrooms stocked with toilet paper" budget is roughly the same as the fusion budget. Oh wait, maybe we haven't been breaking the bank on fusion research after all...
Re:Yeah, tritium's too rare. (Score:4, Informative)
The first wall will contain lithium, which can transmute to T when bombarded by the fast neutrons generated by the fusion reactions. For more info, see Boeing's [boeing.com] blurb on the shield/breeding blanket designs [boeing.com].
Of course, with improving technology, higher beta (a measure of fusion plasma confinement capability), and hotter plasmas, D-T can be forsaken for other reactions. :)
Re:Yeah, tritium's too rare. (Score:3, Informative)
Um, what is an "explosive bond"? I'm sorry but this can never happen. First energy is released when bonds are FORMED, not broken. Second, any chemical reaction concievable can never initiate fusion of nuclei, the difference in energy scales (per atom) between chemical bonds (electromagnetic force) and nuclear bonds (strong force) is orders of magnitude. THAT is why cold fusion isn't real and never will be.
Running out of uranium (Score:3, Informative)
According to the Uranium Institute [uic.com.au], known resources of economically recoverable U-235 are "enough to last for some 50 years" at today's rate of consumption. If prices go up significantly, we could mine other sources, but even so, "all conventional resources are considered - 14.4 million tonnes, ... is over 200 years' supply at today's rate of consumption"
Today, fission supplies 16% of the world's electricity. If we converted the world to using nuclear power for all our electricity, we would use up the uranium six times faster, so all known supplies would last somewhere around 35 years.
To go beyond this, we would need to resort to more exotic technology, such as breeder reactors or extracting uranium from seawater and phosphate deposits.