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Nuclear Fusion Real Soon Now
Mr. A. Coward writes "Researchers at the
National Ignition Facility are attempting to produce nuclear fusion. They'll focus 192 amplified lasers on a pellet of frozen hydrogen. 'NIF experiments will be the first to create fusion that gives off more energy than it takes in.' That will have to be quite a bit, since it will take 500 trillion watts to ignite the pellet in the first place. The facility has been plagued with delays, and so far only 4 of the 192 lasers have been completed. Researchers believe they will first achieve fusion sometime around 2014."
In 1960 we where gong to have fusion in 1980.
In 1980 we where going to have fusion in 2000.
In 2004 we'll have it in 2014.
Things are starting to look optimistic!
Yeah, but it'll only be good for 50 years, and then we'll have to trash it. What a waste...
Umm, fusion is most certainly NOT impossible. Stand outside tomorrow around noon and look up at the sky. See that big burning thing that hurts your eyes? That's a nuclear fusion reaction.
Ahh, hasn't break even been passed experimentally quite some time ago?
m l
http://www.jaeri.go.jp/english/fusion/fusion.ht
This claims break even in 1996, and 1.25 power increase in 1998 in the JT-60 tokamak..
And this article seems to be stating they plan to hit breakeven in 2014 or further out.. hmmm.. perhaps they mean some special kind of break even, like the first ones using our method, or in the US, or something like that..
When Redmond announced Longhorn.
The cost of the lasers and the associated ancillary paraphernalia associated with the fusion plant. If the cost per kWh from the setup and maintenance of the equipment needs to be x cents / kWh and using renewable / clean sources of electricity can generate at x/5 cents / kWh then it wont fly.
Great to see that it is now thought probable that fusion can actually be an energy producer though.
"And we have seen and do testify that the Father sent the Son to be the Savior of the World" 1 John 4:14
National Ignition Facility home page
National Ignition Facility project status and photo gallery with lots of pictures
LLNL Science on High Energy Lasers
it doesn't work like that.
the money hasn't just been going into a big hole with a sign saying "Fusion Power". it's been employing people and adding to our understanding.
sale of foil hats will be at an all time high
We'll certainly need the power of fusion for it.
Let's see...
Assuming that '500 trillion' means 500 x 10^12 watts... They said it would be for a 'few billionths' of a second: maybe 2 x 10^-9 seconds?
Am I counting wrong, or does that come out to about a million watt-seconds, or 0.277 kilowatt-hours?
I consume more energy than that makin' coffee.
Never attribute to malice that which can be explained by mere idiocy.
As Mr. Potts says, Watts are a unit of power. 500 trillion Watts is the power being put into the reaction by the lasers. Energy is not the same thing as power. Power is energy divided by time.
According to the article, the beams will be fully on "only for a few billionths of a second". For a naive estimate of the total energy being output by the lasers, we can simply multiply (500 GW) * (2 ns).
Now, this yields a quantity with dimensions of energy: (500 GW) * (2 ns) = (1 kJ). To get a handle on this, it is the amount of energy that is output in heat and light by a 100W light bulb shining for ten seconds.
For a scenario Slashdotters are familiar with, it's the amount of heat generated by a 1 GHz Athlon thunderbird in 12 seconds.
Let's see, we get fusion in abou 10 years. That's 2014. Maybe 10 years later, we have a terrible disaster. That's 2024. So in 2044, I'm predicting we get a slashdot story about a cute biker chick riding around "ghost town," or what used to be Livermore, California.
Actually, once you've generated it and it puts out more than it received, you can recycle the process indefinitely. then its a matter of harnessing the output effeciently AND saving enough of the overage to eventually set a second chain of lasers firing, then in a few years the power output will grow exponentially and poof, free energy, mass space exploration, colonization, pure research civilization, galactic domination, intergalactic war with insect race, universal domination, peace and love and enlightenment, fin.
its kinda like putting a million bucks in the bank and living off the interest, but also putting aside enough of the interest to increase your returns.
This is my sig. There are many like it, but this one is mine.
Power is not the same as energy. It is energy per unit time. It is rubbish to say there will have to be a large energy output because the input power is high. By way of example, 500 trillion watts for a femtosecond = 500 joules. This is not an unreasonable amount of energy, contrary to the attempt to imply otherwise by shouting '500 trillion'.
Actually, if you read the article 2014 is someone else's estimate, and the scientists hope for results substantially sooner.
/.er actually read the article?
I know, I know, suggest a
Ooh, a sarcasm detector. Oh, that's a real useful invention.
I know a number of people working on NIF and hear of its progress every few months. It's been plagued with problems largely due to budgeting, as scandals have hit the lab and much of the money was funneled out. The LLNL management was largely replaced due to these activities and for a while the entire laboratory was on the brink of being shutdown.
The four beams mentioned in the summary are really just a testbed. In the previous system, Nova, there was a smaller machine called Novet that had the same purpose. I always forget the newer machine's name, but this is standard practice versus a major delay. NIF is behind the original schedule, but that's due to problems (e.g. lens issues) and technical challenges always faced in such large R&D projects.
From what I hear, things will be going pretty well from now on. Since this is an international effort (led by the US), other countries are building their own versions. France has similar system that was brought up last year with help from LLNL personnel and has allowed the lab to avoid many of the same pitfalls the French have faced.
My main contribution to this thread is simply that NIF doesn't seem to be heading towards cancellation, like many government projects. The people behind it are extremely competent and far smarter than I am. The scandals are behind them and will be making steady progress. It's a really, really impressive effort.
"Open Source?" - Press any key to continue
Nothing is wrong with this statement. You are probably referring to the Law of Conservation of Energy, which states, more or less, that energy cannot be created or destroyed. The confusion with nuclear reactions, fission and fusion, is that the reaction liberates energy stored in the nuclei of the reactants. No energy is being created, but more energy (hopefully) is harnessed than was used to start the reaction.
Think of a spark plug in a piston engine. It releases a fairly small amout of energy to start a reaction that releases a larger amount of energy stored in the fuel/air mixture.
Fusion will be a Good Thing once the bugs are ironed out.
It's interesting that the NIF first full light is now pushed back to 2014. There's a small chance we may just beat them to ignigion.
I work at the Omega Laser(still the most powerfull in the world at 60 Terawatts! ya!) and there is currently construction going on here to complete what is called Omega EP(extended performance) by ~2007. Omega EP will produce an astounding 2.6 PETAWATTS(million billion watts!!) of power for a around a picosecond (so about 2-3 Kilojoules per shot which is much less than the NIF's megajoule scale shots) making it, by far the worlds most powerfull laser when complete. The new laser will use what's called chirped pulse amplification to produce its incredibly high petawatt scale power.
Using the current 60 beam 60 Terawatt (~30Kj) laser to compress a pellet of hydrogen fuel and then just before the moment of maximum inward compression and then stagnation; the EP petawatt beam will fire, producing an instant injection of Mev scale electrons directly into the center of the collapsing target and hopefully producing high fusion yeilds and perhaps even approaching ignition. The Gekko XII laser in Japan with its 500 terawatt scale CPA lser has validated this scheme, which is called "fast ignition", reporting that with the CPA laser used at maximum compression with their 12 beam 40 terrawat laser they've achieve an increase in neutron output(fusion yield) by 1 to 2 orders of magnitude...Can't wait till we can fire ours up!
- "Hear that?! The percolations are imminent! Cease your ingress!"
Perhaps we should send a couple of settlers to the capitol and use them to help finish this Great Wonder!
Oops I misspoke, I meant to say the Omega laser is actually the most ENERGETIC UV laser in the world at ~30Kilojoules/shot, Not the most powerfull, as there are a few other chirped pulse lasers with higher powers out there but not higher energies(most can only do a few hundred J per shot though this is still enough to do direct laser induced nuclear reactions).
- "Hear that?! The percolations are imminent! Cease your ingress!"
Who cares? I don't.
We need cheap, clean power. Fission is cheap and clean if done well, but with past waste disposal practices waiting to bite us on our collective bums in the future and certain incidents like that one in the Ukraine 18 years ago in the public memory, I don't think we can afford to risk it. Oil and coal are dirty and running out. Solar, wind, tidal? Useful adjuncts to conventional generation techniques, but blighted by NIMBY and power storage issues.
Everything that has been spent on fusion research could be multiplied tenfold, a hundredfold, and the payoff for humanity would still be worthwhile.
A hundred years from now, I want a fresh set of environmental and social problems. I want our biggest concerns to be the marginal increase in salinity in some ocean currents from desalination plants and some wacky local weather issues due to waste heat from the fusion plants. I want population growth to be a non-issue because of better education of formerly developing and subsistence economies and cultures. I don't even care if my great-great-grandchildren speak Hindi or Arabic or Mandarin so long as the improvement between my life and theirs (materially and in freedoms) is comparable to the improvement between the Middle Ages and now - is it really an issue that I don't speak Middle English, Old Norse, Latin? Or that most of the world doesn't either?I want it to be a world in which pertoleum is seen as too valuable to burn, and as a valuable raw material for manufacturing. I want a world in which it is so cheap to transport and recycle our waste that is easier to "mine" our garbage than process new raw materials.
The thing is, power that is too cheap to meter (at least in personal-use quantities) is going to shake up things considerably. In the West we have all sorts of neat manufactured goods because power is cheap compared with a century ago. Imagine conveying those benefits to Africa, India, China, Iraq without the environmental downside. Imagine a world in which manufactured goods and food are so easy to produce that it doesn't matter that a significant percentage of the population don't make or grow things. Many Western economies are heading towards being services-based rather than manufacturing-based, but we can only continue to do this at the expense of the developing world - unless we can give everybody the same opportunities. We can turn the advent of fusion power into a golden age. Our descendents can wonder at a world in which it made more sense to build something in Beijing than Boston because the people in Beijing were paid less and lived under worse conditions than those in Boston. Our great-great-great-great-grandchildren can scratch their heads in wonder at the fact that people used to get sick and die because they could not afford to heat their homes in winter. They can stare in history books in disbelief, not comprehending what it would be like to live in a world before Universal Service Obligations extended beyond basic telecommunications to the energy necessary to sustain and enjoy life.
So, is this some left-wing Utopia? Maybe. But there's no reason it couldn't be shared by all - except that those currently holding the purse-strings will feel threatened - it's only natural that present energy suppliers may feel this way, although the more astute ones will already be diversifying and looking at possible futures. New industries will spring up that we can't even imagine now. Jobs will be displaced - but will we really need a coal miner then any more than we need cloth fullers now? Half the jobs our great-great-great-great-Grandchildren will be doing probably haven't even been invented yet.
So, when will the great payoff from fusion occur? With the first child's life that it saves. With the better husbanding of the scarce resources of this world, and with access to those of the rest of the solar system (Str
Essentially that's true, I suppose. NOVA was around 100 Terawatts per shot (I've heard it was capable of 100 Kilojoules per shot but I suspect it was actually less). NOVA only had 10 beams though and this ended up creating huge problems. When a pellet was imploded on NOVA the beam/beam instabilities and nonuniformity of the irradiation on target caused very large hydrodynamic instabilities as it imploded (Rayleigh-Taylor instability mostly) which spoiled the fusion reaction before it could really start.
The Omega laser with its 60 beams produces much higher irradiation uniformity and even though it's lower power than NOVA(which was decomissioned in '99) it holds the record for neutron production in a shot at something like 5X10^13 neutrons, indicating a much 'cleaner' convergence and fusion burn. There were several lasers at LLNL before the NOVA laser with various names like Janus, Argus and Shiva, which all used the fundamental frequency of Nd:glass lasers at 1064 nanometers(infrared) and the great contribution in the early '80s to ICF laser fusion by the Omega guys was the idea to convert this IR to its third harmonic at ~351 nanometers in the UV. This greatly increased laser absorption efficiency on target and consequently increased target compression pressures/temperatures accordingly. Allmost all high power Nd:glass lasers use this technique today.
- "Hear that?! The percolations are imminent! Cease your ingress!"
You can buy pure heavy water for about $300 per Kg. Making tritium from that is simple. The AC is delusional, you don't need to make it atom-by-atom. Just put some heavy water need a reactor for a couple of days and you're all set!
As I source I give you this link Heavy Water: A Manufacturers Guide for the Hydrogen Century.
As for his "ideal" proton-proton reaction. First of all it's not in the slighest bit ideal. A Deuterium-Deuterium reaction is the ideal one. You can't make a proton-proton reaction anyway - you need neutrons. And guess what you do with the neutrons? You attach them to protons and make: you guessed it, deuterium!
The only thing the sun does, which we would not do in a lab is convert protons to neutrons by adding electrons. That's the only thing that you are not going to see mass produced in a lab. The sun does not do proton-proton fusion, you can't do that. What the sun does it take protons convert half ot them to neutrons, and hook them up with protons to make deuterium. Then it does deuterium-deuterium fusion.
-Ariel