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Z Machine Advances Fusion Race
Sandia Labs has announced a new milestone in Linear Transformer Driver technology that aims to solve one of the biggest obstacles to practical fusion reactors. Getting the current needed to "spark" a burst of fusion is doable; getting a constant series of sparks going to create a continuous chain of fusion bursts has never been achieved. The LTD, which allows the Sandia Z machine to fire once every 10.2 seconds, makes it look achievable. The press release (which has been picked up in a few places, but with no further analysis) says that practical fusion power could now be 20 years off.
Weren't we closer 30 years ago?
Wow, sent an e-mail as suggested when clicking on "use classic" banner, and got a fast response that addressed my msg
Wasn't it 20 years off 20 years ago?
I think that I'll stand by my idea that even if/when we crack fusion enough to be able to build a fusion power plant it'll have to be so big to be worth it, that they won't be able to get the funding to do so.
Basically, Containment costs go up by the square, while energy release goes up by the cube. To make it worth it, we might be looking at a 100 gigawatt reactor*, of which half goes towards sustaining the reaction.
*1-2 gigawatts is a pretty big reactor today.
I don't read AC A human right
> says that practical fusion power could now be 20 years off.
Twenty years off what? And are they light years or dog years?
Cold fuses you!
A stunted oak tree shades the inland road.
Badass Resumes
Well, since every comment here is about that "20 years off" quote, I'll add mine.
That twenty years (here and decades ago) assumes that governments won't pull funding for fusion research. But they did, and will again. ITER could have been built years ago. It wasn't a lack technology holding it back, it was a lack of money. So don't blame the scientists who give those 20 year estimates, blame your governments.
Wouldn't be more honest to say "We have no clue when fusion energy will be practical. Maybe some fundamental research breakthrough will make it doable next year, maybe we need to struggle with the current approach for another thirty years. Please fund research" ?
Nuffsaid
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Don't know about his cat, but Schroedinger is definitely dead.
Actually, measured in light years, practical fusion is only 1.58e-5 light years away.
Fusion reactors could produce some short lived waste, but they are not prone to melt down and so don't need the heavy containment that fission reactors require in most countries. Table top fusion is also advancing so I'm not so sure things have to be big to be useful. For Tokomaks this probably is a requirement but not neccessarily for other methods.s -selling-solar.html
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Mr. Fusion on your roof: http://mdsolar.blogspot.com/2007/01/slashdot-user
It is worth noting (and it is also mentioned in TFA) that this development advances the field of Inertial Confinement Fusion, which is an area that has not traditionally been considered the most likely candidate for commercial fusion power generation. ITER and all other experimental tokamak reactors are of the other variety (magnetic confinement fusion), where a magnetic field is used to keep the plasma in place during the reaction. During ICF, each fusion reaction has a duration short enough that it isn't necessary to hold the plasma back against the forces of gravity. Hence the need to produce a "spark" quickly and efficiently, as many consecutive reactions are necessary to produce any significant amount of power. http://en.wikipedia.org/wiki/Inertial_confinement_ fusion
The article lacked a photo of the Z Machine in operation. Amazing!
I think the 30 years joke is a bit passe. In realilty, the funding for fusion has suffred some major hits in the last 30 years after the big spike in the 70's. To measure a field's achievment in years is somewhat nieve, as total funding dollars is more realistic. If 1970 funding dollars had continued for the next 40 years, I think we would be there now, but alas we will have to wait for the money to trickle in. Iter is a great step forward, but work in innovative concepts that are alternatives to the tokamak are also good in looking for economically viable fusion schemes.
Practical fusion power is always 20 years from the present. That was true 40 years ago, it is true today, and will be true 40 years from now. This is a little known consequence of general relativity.
Bad choice of name. The Z-Machine, which is short for Z-Pinch Machine is a fusion confinement machine that has been around for five and a half decades. http://en.wikipedia.org/wiki/Z-Pinch Numerous experimental devices have been built around the world in government labs and universities.
Contrary to the misconception people keep throwing arround, it wasn't 20 years of 20 years ago. The confusion arises because one was talking about different things. One estimate was when we would reach break-even. That eastimate was for year 2000, and at the time ( 1970) it was 30 years into the future. As it happens, the JET reactor has managed to heat a plasma to the temperatures needed for break-even, but that doesn't mean it is practical as a powerplant. I have a 30 year old book about electricity generation, which estimates the first powerplant for 2050. Furthermore, last time I heard "it was always X years ago", X was 30. Before that X was and had "always" been 50 years ( Tho my Swedish book still says 2050 and was written in the 70ies ). I bet in 2040 we will hear people saying how widescale worldwide deployment of fusion powerplants was "always" 10 more years. When in fact, the estimate of today is that the technology needed to build a practical powerplant ( not necessarily an economically competative one ) is 2027. These "that is what they said back then" quotes usually have no substance in reality. It is just like saying "well they said chernobyl was safe", which of course nobody ever claimed ( in contrast the department of energy stated that no water cooled graphite moderated reactor would be licensed in the US ). However, the claim sounds so damning that people want to believe it. It is the same thing with fusion. The scientists never claimed we would be using fusion plants today. They claimed that IF funding was continued, and IF projects were not cancelled, then we would be able to have a controlled fusion reaction by the year 2000. As it happens we have done better than that. We have managed to initiate fusion reactions that produce more energy than is needed to sustain them. This is however not the same thing as an economically competative powerplant, and it is not the same as ignition ( a fusion plasma that needs no external energy input once it is burning). If you keep changing the goal to be something more difficult, then yes, the goal will always be in the future, that doesn't mean the original estimate was wrong tho. It just mean you were talking about something else.
The original hydrogen bomb was known as the "Super" before it was called a hydrogen bomb, and the idea is what every wide-eyed geek in elementary school imagines the H-bomb to be -- put an A-bomb next to a vat of deuterium, and the A-bomb blasts the deuterium hot enough to make it fuse.
As the dudes as Los Alamos started building computers to do numerical models of fluids and radiation and everything, it became apparent that Teller's Super was a dud. The physics of radiation were such that simply sticking a fission bomb next to a pile of heavy hydrogen was simply not going to do anything. What if you sweetened the deuterium with tritium -- then what? As it turned out, you would need gobs of tritium, so the whole thing was a non-starter.
As it turns out, Stanislaw Ulam came up with the idea of a staged atom bomb -- a small atom bomb would provide the shock to compress a big freepin pile of plutonium to make a big honkin atom bomb, and Teller got ahold of that idea to make the staged H-bomb. The staged H-bomb used to be a very dark secret, but the combination of Richard Rhodes "Dark Sun" and that Progressive Magazine article kind of let out at least the general H-bomb concept. Teller's stamp on the staged bomb was that prompt x-rays from the atom bomb would be the way of getting compression instead of Ulam's original idea of the shock wave, but that the radiation would act first is obvious once anyone with physics knowledge starts working on a staged design, and Teller kind of took all the credit.
But the actual staged H-bomb not only focuses A-bomb radiation to compress a pile of deuterium, it also compresses a plutonium "spark plug" in the middle to make Ulam's staged A-bomb. The combination of heat and pressure from the radiation compression along with the flood of fast neutrons from the plutonium spark plug manage to fuse the deuterium, which produces its yield mainly in the form of yet more neutrons, which provides fission of a U-238 blanket to provide much of the explosive power of the bomb.
Fusion is really, really hard, even with the heat and pressure from an atom bomb, and the real H-bomb is a Rube Goldberg set of multiple effects which use fission-driven neutrons to produce fusion neutrons to produce gobs of explosive power from non-critical fission of U-238. Fusion is really, really hard, even for the Sun, because while the Sun is not using deuterium but straight hydrogen, for all of the intense heat and pressure in the interior of the Sun, the reaction rates are really, really low, which is a good thing, because otherwise the Sun wouldn't have lasted 5 billion years to allow us to be here.
So back to the fusion power reactor. All of the claims of imminent fusion power are based on using lots of tritium for D-T fusion for the same reason that Teller's Classical Super would have needed gobs of tritium and for the same reason that the actual H-bomb that burns D-D needs three stages of fission to get its explosive power. Just as the need for tons of T made Teller's Super a non-starter, the need for tritium means that the current frontier of fusion power is a non-starter. Yes, you breed tritium in the lithium blanket, but you have to compare the breeding doubling time with the half life of tritium and wonder how much seed tritium will you need to get a fusion power economy going and how many decades of breeding tritium will be required to switch the economy over the fusion power before the oil runs out.
I remember seeing a powerpoint lecture given by one of the researchers there, who calculated that to make the Z machine feasible for providing fusion power, they would need to fire one of these off every 0.1 second, so once every 10 seconds is not even close. Plus, the simple fact that there's an enormous explosion going off ten times a second, which destroys the chamber that holds the capsule, makes it seem like there's a definite engineering feat to overcome, otherwise the whole thing is liable to crumble to bits. Right now, they only fire off the Z machine a few hundred times a year... going from that to a few hundred times a minute is a big step.
I also wouldn't want to live anywhere near there; it feels like a moderately strong earthquake in the area everytime they fire that thing; it seems like the ground beneath and around a rapid-fire facility would quickly weaken and collapse.
So yes, the Z machine is an excellent source of x-rays, and those x-rays can definitely be used to collapse a fusion capsule, but how applicable is it for fusion power?
Fuck "in God we Trust," we should just print "don't rock the boat" on our money.
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
Interesting, how that relates to Rober Bussard's Polywell fusor, which he claims can be made into a prototype 100 MW plant in 7 years, provided the needed 200M USD funding?
You can also listen to his lecture at Google Tech Talks in 2006 to get an idea of what he's up to.
BTW, you can donate to this fund via Paypal and sign the petition to renew his funding from the government.
One thing I don't think many people realize is that everything leading up to and including fusion are just heat sources for boilers that power steam turbines. ... all just big old steam engines.
Wood, Coal, Fission, Fusion
Has the efficiency of steam turbines progressed much in the last 50 years?
After fusion would it be better to focus on Steam turbines or the removal of the steam cycle from the power generating equation?
Thermocouple technology would probably be better in the long run than steam technology moving turbines around.
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.....Fusion is really, really hard, even with the heat and pressure from an atom bomb.........
Why spend billions re-creating something on earth which already exists 93 million miles away -- the sun.
It has been keeping us warm and feeding for millennia. The fossil fuels we now burn are nothing more than stored solar energy. This means that all that carbon we are now releasing must have been on the surface of the earth at one time in order to participate in photosynthesis. For that reason alone, all this global warming BS is just that BS and should be ignored. If living plants and animals flourished in such abundance, to create all these fuels, then why exactly would the return to a warmer, more life filled planet be such a terrible thing? Living things, especially people, are very much able to adapt to changing environments, if the changes are gradual. Would growing oranges in Alaska or Siberia be such a terrible thing?
There is this yet poorly understood, yet ubiquitous process called photosynthesis in nature for capturing the free energy this giant thermonuclear fusion device sends our way. It has ben working for untold amounts of time. We figured out already how to refine common sand to make devices to convert some of this energy for our needs. There is a band of wind called the jet stream circling the earth at high velocities. Utilizing only 1% to 2% of its energy would meet all human needs all by itself. Learn how to fly a windmill kite 7 miles up and get the power down to earth.
It seems to me that developing these partially working, known technologies should bear fruit much sooner than pie in the reactor fusion.
All theory is gray
Care to cite your sources on this? Because the IPCC report that was published recently suggests almost the opposite. Already warm climates will become warmer and drier, not more humid; in those climates, water tables will drop as soils are dried out (which also contributes to topsoil erosion due to wind).
As someone else said, who cares if you can grow oranges in Alaska if the bread basket can't continue producing enough for everyone?
In Arizona, we've been seeing abbreviated monsoon seasons and dropping water tables for over a decade. Granted, some of this is attributable to the burgeoning population... but somehow, I don't think the reduction of monsoon rains is completely attributable to population growth. We're also seeing fewer hard frosts in the winter, which means some pest populations (like ticks) are growing out of control.
Again, care to cite a source or provide an argument to support your claims? Because the IPCC report predicted that, for example, a 2 degree C temperature increase might benefit crop yields in North America overall, but any increase beyond that was almost certain to have a negative impact.
The effects in Africa and Central America are predicted to be the most profound, since agriculture in those areas is tied to rainfall, and rainfall patterns will most certainly be disrupted by higher temperatures. Combine that with drier soils that get blown away, a la the Great Dust Bowl, and you have a recipe for disaster.
Of course, this is starting to get WAAAAY off topic. Bringing it all back to the original article, and to your comments upon it: Yeah, practical fusion may be a long way off, but the technological benefits just from trying to achieve it are going to pay off big-time. I am particularly heartened by the fact that the approach taken by the researchers in TFA is substantially different from the magnetic confinement approach taken by the tokamak proponents (e.g., ITER). More teams trying various different ways of achieving fusion means an increased probability that one of the approaches will bear fruit.
In the meantime, there are other sustainable energy sources we can exploit, and still be carbon-neutral. Yeah, it's possible that humans could adapt to some dramatic climate shifts, but what would happen to most civilizations on our planet? What would happen to our cultures? These impacts need to be weighed too.