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Laser Fusion Passes Major Hurdle
chill writes "The National Ignition Facility at Lawrence Livermore National Laboratory has performed their first controlled fusion experiments using all 192 lasers. While still not ramped up to full power, the first experiments proved very fruitful. The lasers create a lot of plasma in the target container and researchers worried that the plasma would interfere with the ability of the target to absorb enough energy to ignite. These experiments show that not only does enough energy make it through, the plasma can be manipulated to increase the uniformity of compression. Ramping up of power is due to start in May." The project lead, Dr. Sigfried Glenzer, is "confident that with everything in place, ignition is on the horizon. He added, quite simply, 'It's going to happen this year.'"
Clean, safe, American-made, no foreign oil, low level of pollutants, and a reasonable amount of entropy (heat) released. Sounds like a winner to me.
Just don't take it any faster than 85 miles an hour.
Unless you want to visit the '80's, the '50's, or the old west.
Official Heretic from the "Church of Global Warming". Proven right thanks to whistle blowers. AGW = Flat Earth Theory
However, just as with fission, it's likely nothing will be built without massive amounts of subsidy, and it will pay off only in a span of decades. Unless the public and officials are willing to think longterm, fusion is going to be delayed regardless of whether the technical hurdles are overcome.
Now fusion energy is only 10 years away!
The project lead, Dr. Sigfried Glenzer, is "confident that with everything in place, ignition is on the horizon. He added, quite simply, 'It's going to happen this year.'
Huh. I had always thought that some international police force like "The International Fusion Gestapo" would be dispatched upon hearing this news and show up at your lab and start smashing mirrors and urinating on lasers until you revised your statement to be "15 to 20 years away" so that all their dues paying members would have time to reach tenure before you ruined the party.
I mean, there was no other logical explanation why so many seemingly brilliant scientists continually gave us incorrect estimates of achieving milestones in fusion research. Is this just being overly optimistic or was he carefully picking his words so that they will know if this method is viable (above break even energy production) or not within a year? And if so, where will he get his funding given the if not scenario?
My work here is dung.
but its low powered and has quick half-lives. additionally, there are no geopolitical overtones concerning fuel sources: you just need sea water. no climate changing pollution/ city-choking smog for that matter. no peak oil this or that, no bubbles and spikes in supply or pricing
additionally, if everyone had electric cars, there would be no petrodollars funding saudi arabia, a backwards fundamentalist regime that funds wahhabi madrassas in places like pakistan, that give rise to all of these well-funded (from saudi "charities") militant assholes in the muslim world
no funding of gas bag chavez in venezuela, no funding of neoimperial russia and putin, no funding for nigerian graft and corruption...
it will take a long time, but if we can remove the reason for the world to have any vested interests in backwards regimes, propping them up and preserving them unnaturally, and we instead let these regimes instead rise and fall on their own intrinsic value in governing fair societies, then we will have taken a mighty step forward in terms of progress in this world
of course, it will be decades before we're all driving electric cars powered by fusion plants. but one can dream, cant' they?
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
Why aren't they using an array of neural-network-controlled, articulated metal arms to control the fusion chamber?
Dewey, you fool! Your decimal system has played right into my hands!
What is wrong with a pay off in decades. This "profit now" attitude is going to kill America. You think the interstate system paid off sooner than decades? You think the interstate system was a failure?
My addiction: Arguing with idiots. AKA Slashdot!
Are you sure it's wise to ignite your nation?
I'm glad that there's plenty of water between me and the nation in question.
What's really scary, being a kid at the time the movies came out, is that pretty soon the "future" they visit in the second movie will be our past (we're only five years away)...
Ignition means more fusion energy released than laser energy in. Yes, there are issues in scaling it up, but none that are known to be insurmountable. Already there have been experiments to look at target injection (a 2 GW power plant would be at the 5 - 10 Hz region), high rep-rate lasers (Mercury is an example of a high power, high rep-rate laser) and the lining up of the laser in this situation requires less precision than that of anti-missile systems that are around.
Also the Hohlraum approach is unlikely to be used in a power-plant, as it doesn't give the biggest energy gains, so this is basically a significant step towards projects such as HiPER. If NIF achieves success in ignition as is widely expected the money should be around for projects like HiPER.
You think the interstate system was a failure?
Well... given that the existence of the interstate infrastructure created the incentives that destroyed the locomotive as the main means of in-land shipping in America, and in other ways promoted the reliance on the automobile that's ended public transit in most areas and greatly exacerbated global warming... possibly yes. : p
But I think the parent's point was actually the same as yours -- cynicism about Everybody Else's willingness to do something that'll have a profit after the next quarterly earnings report.
Freedom isn't free; its price is the well-being of others.
And, let's admit everything works: what quantity of nuclear waste will such a machine produce? And of what type?
Don't give me the "it's fusion, so it's clean, duh" line: this machine is going to generate an enormous amount of energy and a lot of that will in the form of a "carefully controlled thermonuclear explosion" (BBC dixit) -- which means radiation, which also means neutrons. And neutrons are not really good for your health.
Later in TFA it says they'll eventually be fusing a fuel containing a mix deuterium and tritium. Deuterium-deuterium fusion yields tritium and a neutron, and deuterium-tritium fusion yields helium-4 and a neutron. So the byproducts are Helium-4 (not radioactive in the slightest) and neutrons.
High energy neutrons are very bad for you, yes, but that just means you won't be standing near the unshielded reaction chamber. It's not like you have to dump a big pile of poisonous neutrons somewhere. The neutrons will affect the containment itself, but the biggest problem there is just that it becomes brittle, not necessarily radioactive.
It is basically true that fusion is clean. The waste is minimal.
The enemies of Democracy are
It was Doc Fucking Brown, not only was that speedometer perfect, it was digital.
"There are no facts, only interpretations." --Friedrich Nietzsche.
And can it sustain power generation?
You're talking about zapping a very small, supercooled, gold-uranium alloy target with a beryllium sphere containing about 1mg of DT fuel, about 10 times a second.
Have a thought experiment about the engineering involved
what quantity of nuclear waste will such a machine produce?
DT fusion produces fast neutrons, so some. You're looking at much shorter half-lives ; the reactor core will have the same activity as coal ash after about 300 years.
And will ITER be quickly refactored to take this into account?
ITER is a totally different design, so no. I think ITER is a far more credible design than laser-fusion, given that the engineering challenges seem some orders of magnitude easier.
NIF is just a testbed for nuclear fusion, without the inconveniently illegal use of real nuclear weapons.
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If you're firing at 1mg of fuel, by mass, 3/5 of it is Tritium or 0.6mg so (60 * 60 * 24) seconds in day * 10 per second * 0.0006 g = 518.4 g of tritium per day.
The total production in the USA between 1955 and 1996 was 225kg ; the stockpile in 1996 stood at 75kg
AFAIK, this method of fusion is not nor will ever be self-sustained -- it simply doesn't work that way. You have to repeatedly fire the laser, once per fuel pellet. Once the pellet ignites, energy is released. After it's released, the pellet is exhausted. To release more energy, you have to insert a new pellet and repeat. It's not like there's a lot of fuel at the focus of the lasers that just needs one firing to ignite the fuel and it will chain-react. The only way to have a chain-reaction sustain itself with no input of energy would be to have the fuel at the high pressure and high temperature that's found at the core of a star. The laser temporarily creates a tiny spot of such pressure and temperature, but there's no way the reaction can sustain itself without repeated firing of the lasers.
If you reply, do so only to what I explicitly wrote. If I didn't write it, don't assume or infer it.
Don't worry, as soon as anything explodes, someone dies, or they find a "scientist" who can worry and fret, Foxnews will point out how Obama's DOE is funding crazy apocalypse engines.
Unfortunately, we need a populace that is capable of looking to the future as well. Without that, we'll never get the political structure you're describing. People don't vote for politicians who spend money on long term projects.
I'm a physicist, I love these experiments, but...
The people running this thing need to think really, *really* hard how their comments play out in the media, maybe try and be a little more clear. The difference between getting fusion (the physical process) to work and getting fusion (the power generation system) to work is huge! Should they accomplish their goals in a year, they will still be a very long way away from thinking about building an electricity generating system. The line of "getting more power out than we put in" for fusion in the lab was crossed decades ago, and it's still unclear how doing this with yet another method of creating a fusion plasma is going to result in a more straightforward commercial reactor design.
This is how we end up with government officials who think we're all full of hyperbole, and don't actually do any work. I know they're fighting for their jobs at Livermore, but I don't see how they can keep this up long term. At some point, some Congressional committee is going to ask them to deliver on what has been promised, even if it was a confused, incorrect promise mis-translated by the media.
I agree with most of what you said but I don't know where you got "and the lining up of the laser in this situation requires less precision than that of anti-missile systems that are around". That's definitely not true. Laser irradiation on a direct drive target for ignition requires exquisite precision. We recently demonstrated a significant hit on fusion yield in implosions of cryogenic, layered deuterium tritium ice capsules when beam pointing was off by TEN MICRONS. If you're injecting targets into your reactor chamber at 10Hz, you are going to need some serious, super accurate laser pointing unless you want your fusion yield to be severely diminished. That means real time tracking of the target with hundreds of final focusing lenses that are all about 10 meters (at least) away from the target chamber center. Good luck!
You don't even want to get into the problem of the cryogenic microcapsules melting before they reach the target chamber center. I've seen DT ice filled microcapsules melt, boil and explode within ~3 seconds of exposure to the thermal radiation from the inner wall of the TC at ambient temperature. Wanna take a guess as to how much that time is going to be reduced when your TC is at 800 Kelvin reactor operating temperature? Yeah, that means you are going to need to inject the pellets at extremely high velocity to minimize the thermal exposure time, and your lasers will then have to track it that much faster. Furthermore, how the hell do you deal with the horrible vibration on your focus lenses created by detonating the equivalent of roughly 50 pounds of dynamite (200 MJ) in the TC at 10Hz. Yeah... I'm as excited about this as anyone, but we have a LOT of problems still left to solve.
- "Hear that?! The percolations are imminent! Cease your ingress!"