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Fusion Plasma Plant in The Future
NightWulf writes "The BBC reports that Europe and Japan are currently looking to host a new JET power plant. This new plant creates plasma, which is akin to creating a star on Earth. Interesting to note that 1kg of fusion fuel would produce the same amount of energy as 10,000,000kg of fossil fuels."
Step away from the car... This is a fusion research reactor, not a reactor to be used as a power source...
does this solve the energy problems?
Do you need a website upgrade?
you idiot. Fusion can not go Chernobyl, and the only radio activity is the Neutron bombarded walls of the chamber which dissipate quickly enough to not be a big problem
I am the Alpha and the Omega-3
why? vented Plasma is not toxic.
read about Fusion from Wikipedia please and cure your ignorance before you start some crazy anti-fusion lobby
I am the Alpha and the Omega-3
Deuterium... cheap. The oceans are full of the stuff. Tritium and helium-3 are harder to come by; we'd probably need a lunar harvesting operation if we were going to go for fusion on a commercial scale.
Real Daleks don't climb stairs - they level the building.
If anyone is interested there is a wealth of information on JETs website
Including some pretty cool pictures of their kit.
50-100 years is nothing, and it's not the fuel or exhaust that you need to worry about, only the parts of the reactor itself that become radioactive from neutron bombardment. So, we only need to store retired reactor parts for 50-100 years, which is much less mass and much less duration than what we currently produce from nuclear plants, and massivly less environmental impact when compared to the equivilent fossil fuel usage.
Goodness -- I was surprised by the number of wildly incorrect postings about nuclear fusion. Some I could have tried to clear up myself, but a better recommendation would just be to read up for five minutes before posting some misinformed comment.
Wikipedia has a good article on Fusion Power. Read it, then post.
Not much. The waste produced by a fusion reactor is helium - probably the most harmless stuff you can get. The process of fusion produces neutrons, so the fusion container itself will become mildly radioactive, but nowhere near the kind of nastiness you get with fission.
In addition, fusion is inherently fail-safe. If something goes horribly wrong with a fission reactor, you can get a runaway reaction. Meltdown. Not good. But in a fusion reactor, you have to carefully maintain the right conditions for the reaction to happen at all. Screw up and the light goes out, that's about it.
Real Daleks don't climb stairs - they level the building.
No, but you can get helium-3 out of the regolith, where it's been collecting in small quantities for a few billion years out of the solar wind.
Real Daleks don't climb stairs - they level the building.
But since when do we power our power plants with oil?
We will always depend on Arab oil in some way or another.
Oil is used to make plastics, and from what I see it seems like everything is made out of plastic.
American cars for one.
So the Arabs will find a way to still charge $100.00 a barrel.
I think perhaps you don't grasp the fundamentals of what a magnetically confided burning plasma reactor really means. While a reactor of this sort aims at providing net power production via nuclear fusion, you have to be aware that a significant amount of energy is used to create the magnetic fields, and other auxillory control mechanisms like nuetral particle beams and radio/microwave power used in controlling the plasma to get the very precise conditions under which net power can be achieved. You turn off any of these control systems..the plasma start under performing. Unlike fission, you aren't trying to control a run-away process by slowing it down. In terresterial magnetic confinement fusion reactors..you are doing everything you can think of to produce the very specific conditions that maximize the amount of nuclear reactions. And if the plasma conditions change or your control system fails, plasma performance quickly degrades on its own because of naturally occuring instabilities in the magnetohydrodynamics that govern bulk plasma behavior.
Nothing like a world ending 'meltdown' can happen, a magnetically confided plasma has so many different ways to dissipate energy. The trick has always been and always will be to get enough nuclear reactions out of this plasmas to make it worth while to build them as an energy source, becuase running them invovles using lots of energy just to create the plasmas conditions at all.
No need for us to prove it. You can do it yourself. The equation is E=mc^2. c is a really big number.
How can we continue to believe in a just universe and freedom to eat crackers if we have no ale?
The plasma is VERY thin... and there's a reason why they have to try very hard to keep it away from the reactor walls. Not because the walls will melt but because the plasma will instantly cool down and stop doing its fusion thing.
"Studies have shown that people who eat peanuts live longer than those who do not eat."
Iter - latin for "road" - is the next stage, but not the final.
It will produce more energy than put in, will will not create electricity as such.
"Creating" electricity, as a normal powerplant does, will be the next stage. As in DEMO.
So another year before knowing where to build iter, it should have been decided long ago. A few years to build it. 20 to 30 years of research. A few years op political maneuvering for deciding demo, building and doing research for another generation.
So 50 or 60 years before we have an electricity producing fusion plant.
For a brief primer, read this article.
I'm not tense. I'm just terribly, terribly, alert.
But whats the possible damage if one of these plants pulls a Chernobyl on us?
Well, the most significant damage would be to our understanding of physics, since there is no possible way that a fusion reactor can "run away" like a fission reactor can.
Think about it this way: for a fusion reaction to happen, the outside control is critically important: in typical designs, the control is provided by huge electromagnets (magnetic confinement) or by powerful lasers (intertial confinement). If the reaction did somehow get "out of control," the first thing that would happen is that the control systems would be destroyed, and there would be no way to keep the reaction going.
Compare this to a fission reactor, where the reaction can proceed without any outside control whatsoever (for example, the natural uranium reactor in Russia or wherever that was). That is why there is so much effort currently put into designing "passive safety systems" for fission reactors - which are basically hacks that make a fission reactor behave as if it could not work without outside control.
Honestly, if it were so easy to get a runaway fusion reaction (in non-bomb form), don't you think we would have achieved one by now?
Alpha particles - helium core - and neutrons are created in a fusion reaction. The alpha particles carry about 20% of the energy, the neutrons about 80%.
After the alpha particles give of their energy to the surrounding plasma, the have to be removed in order to keep the fusion reactions going.
So left are the neutrons. These are neutral particles. So forget about something like an ion-separator (sorry, don't know the correct english term. same principle as an ion-engine. Using lorentz force: f= qE + qvxB).
So you use the energy of the neutrons to boil water.
Aside from the initial jumpstart of energy required could it not sustain itself afterward using its own energy, perpetually maintaining itself once stability has been established?
Keeping the plasma hot enough for fusion to be possible is only part of the picture; you also have to solve the confinement issue. You not only have to keep the ionized plasma confined (and no, a material "containment vessel" similar to what's used in fission reactors doesn't work; you need something nonmaterial, such as strong magnetic fields), you also need that confinement to be within a very small volume for reaction rates to be sufficiently high (for any kinetic "collision"-ish process, reaction rates are proportional to the square of the density). Heat is necessary for the nuclei to be moving fast enough for fusion to take place; but heat is also the enemy of keeping the plasma at high density.
JET reached (or came very close to) the break-even point (produced as much power as it consumed). ITER will surpass it and actually generate power. (5-10x as much out as is put in, so that would mean that the heating required during fusion would be around 50-100MW). See here, for example.
It's also designed to be repairable in the event of a failure (in the way a commercial reactor would need to be), and its designers have benefitted considerably from the experience of JET. The BBC has covered this reactor for some time: I'm surprised slashdot has only picked up on it now.
Let me point you to the sun as an an example of what it takes to keep fusion conditions viable over long timescales without extra energy input. Thats a hell of a lot of mass to produce the gravitational energy to keep a burning plasma self-confined, not to mention the large scale bulk motion of the solar plasma that is still not completely understood that allows the sun to create its own magnetic field via a dynamo effect. Regardless of what the open scientific questions about how our sun and other stars operate, few if any competent researchers will argue that a self-sustaining magneticially confined plasma is something that can be created on earth, simply because of the scales invovled to produce a dynamo. Earth's core for example, is probably a good example of the amount of material needed to produce a dynamo..and thats not even a fusion plasma..just a magnetic dynamo..getting to the much higher pressure/temperature conditions required to produce a self-sustaining magneticlly confided plasma will require stellar mass.
-jef
Exactly. Let me spew some physics for a moment.
The temperature of a gas is related to how fast the particles of the gas are moving. The hotter the gas, the faster the average kinetic energy. However, not all the particles move at the same speed. There is a distribution of speeds, with most of the particles at or below the average speed. However, a very thin "tail" of particles travels at speeds much, much higher than the average. In the Sun, it is these very high-speed nuclei, way above the average kinetic energy of the plasma, which collide and fuse.
So, why can't we get fusion with temperatures equivalent to the center of the Sun? Pressure. We can't hope to achieve pressures anywhere near that in the Sun. In the sun, the pressure is so immense that the particles are squeezed extremely close together. Imagine these particles moving at insane velocities, in such close quarters. They will collide with each other extremely often. This extremely high collision rate allows fusion to occur, because it brings the super-high-energy nuclei together more often.
On Earth, at very low pressures (at least relative to the core of the Sun), the particles are moving fast enough to fuse, but they just don't collide often enough. They aren't close enough together. Thus, to make up for this, we must increase the temperature so that a larger fraction of the particles are in the kinetic energy realm where fusion can occur. In other words, we make up for the lack of pressure by increasing the temperature.
A quick Google reveals a current price of about $300/kg for heavy water, which must include the energy costs of separating it. Deuterium is 4/20 of this, so about $1500/kg for pure deuterium. Prices will probably fall with real mass production.
Consciousness is an illusion caused by an excess of self consciousness.
Seastead this.
Oh, and as an added bonus for geeks in that area, they have a public open house coming up on June 12!
The part that becomes radioactive from neutron bombardment is called the "reactor vessel". It weighs about 1000 times as much as the fuel in a fission reactor. The irradiatted iron/nickel/chromium/cobalt/whatever-else-is-in-yo ur-alloy-of choice has a much shorter half-life, and this is far more radioactive than the spent fuel rods.
You'd probably get more irradiated metal in a fusion reactor than a fission reactor, though this no doubt depends on design details. But the neutron flux will be higher, per watt, so expect it to tend toward more radiatted metal rather than less.
In other words, don't expect fusion to be cleaner than fission. There'll be a different mix of radioactive byproducts, but it is by no means clear that there will be less, or that said byproducts will be easier to dispose of.
"I do not agree with what you say, but I will defend to the death your right to say it"
"Helium causes death??? Come on; get real. Helium is an inert gas (if you don't know what inert means, look it up). It is not a poison and it cannot hurt you by breathing it. Divers use a mixture of helium and oxygen when they go deep because pressurized nitrogen is poisoness. The only way that helium could hurt you is if you were breathing pure helium (no oxygen). You would pass out and eventually die from a lack of oxygen not from any property of helium. This is true of any gas that you might breath that does not contain oxygen.
If you are sucking on a helium filled balloon and start to get light headed, just pull the balloon out of your mouth and take a breath of normal air. If you don't stop sucking on the balloon when you get light headed, you will probably drop it when you pass out and the problem will fix itself."
Please stop spouting Urban Legends that have no validity.
There are some fission designs that require active intervention to remain active, and have been in active production in Germany and South Africa.
c to r
My understanding is that these designs have been ignored in the US due to the costs to get approval from the Nuclear Regulatory Commision are too high.
http://www.wordiq.com/definition/Pebble_bed_rea
plus-good, double-plus-good
I don't think that was the question the poster asked at all. Its a very complicated process to turn the nuclear energy released in a plasma back into electricity, and requires a metric buttload of human effort.
The goal of course of any fusion reactor is to get enough energy out than it takes to produce the fields and other things...to produce net energy that can be put to use. The point at which this happens is called break-even, there is a handy dandy ratio called Q=power-out/power-in that gets used to describe the reactor power. Q=1 is break even...the reactor produces just enough energy via nuclear reactions to make up for the energy needed to be spent by humans to power the reactor. Of course what goes into defining Q is sort of dependant on who you talk to. The efficiency of turning the energy released in the nuclear reactions into electricity is a matter of debate. The process we do most efficiently is turning steam into electricity...turning fast moving energetic nuclear particles into steam is something we aren't really good at doing. Anyways...i digrest.
The point at which a plasma is self-sustaining is Q=infinity and is called ignition. Plasmas that ignite, don't need external power sources to continue their fusion processes. They go about their business all by themselves if given a supply of fuel.
Production reactor designs aim between something like Q=5 to Q=20. At first glance a higher Q value would seem to be a better thing. But actually it isn't. Q isn't just a measure of how much net power your are getting out, but its also a measure of how much control you have over the plasma itself by external means. It could very well be the case that the most economical reactors long term are ones that can be better controlled at Q=5 than higher performing Q=20 reactors.
-jef
http://www.nrel.gov/geothermal/geoelectricity.html
Prolonged neutron bombardment makes many metals brittle. Fortunately it is a relatively well understood phenomenon which is familiar from the operation of current reactors - some of which have run for over 40 years.
Fusion reactors can expect some embrittlement with time, but the consequences are much less likely to be serious than with a pressurised vessel such as a PWR.
The biggest problem will be that the plant will have to be mothballed for a period before dismantling at the end of its life. Again that is something we know about as the US and UK are already dismantling their first generation of nuclear reactors.
Best wishes,
Mike.
The US already has at least one of these already.
The Princeton Plasma Physics Lab in Princeton, NJ has been experimenting with fusion since 1951.
I've toured the reactor, in addition to working there one summer, and it is a very fascinating technical achievement. Basically you have a large magnetic containment device (big donut) which contains a vacuum. The vacuum and the magnetic field keep the plasma from melting the containment device. Tritium (used to be deuterium) is placed inside and a huge amount of energy is pumped into the donut converting the gas inside to plasma with a temperature hotter than the interior of the sun allowing fusion to take place. Currently the amount of energy released is less than the energy needed to generate the fusion.
To give you an idea of how much energy is needed. The energy from the localpower company is used to get a bunch of giant dynamos spinning. To get the dynamos up to full rotational speed takes, IIRC, about 10 hours. All this stored energy is then released all at once.
The vast majority of their power is Nuclear, I was suprised .
77% Nuclear
14% Hydro
8 % Fossil
1 % Other
Thanks,
Ex-MislTech
google "32 trillion offshore needs IRS attention"