Slashdot Mirror
Fusion Gets Closer With Magnetic Field Correction
jparadise writes: "Seems folks over at the
the U.S. National Fusion Facility in San Diego have figured out a way
to fiddle with magnets to contain plasma and make their scale-model fusion generator produce energy significantly in excess of what they're putting in. It's not the final answer, doesn't look like, but it seems (maybe? hopefully?) like a step in the right direction ..."
Without the huge projects funded by military research you wouldn't have things like telecommunication satellites, microwave ovens, nuclear energy, computers... the applications are far off and many times not immediately visible (like from the creation of a computer until the big breakthrough of home computing and the internet was 50 years), but the gains are exponential. You couldn't do your protein folding research to find cure for cancer without those supercomputers...
My father started working on fusion at ORNL in 1969. At the time, scientists though they could build a commercial reactor in about 25 years. Every 5 years they would revise the time frame -- "We'll have commercial fusion in 25 years." I'll bet we are still 25 years away from commercial reactors.
One problem that I did not see discussed in the article is the neutron problem. Neutrons are a byproduct of working with tritium. They can't be contained in magnetic field. They also tend to embed themselves in the walls of the reactor vessel where they will eventually weaken the vessel itself. Has any progress been made on this problem?
I wish one of those eco-terrorists would try and mess with some of my property. I would laugh as I shot him in the gut and watched him die a slow, agonizing death.
The DOE has generally budgetted more money into ICF fusion then magnetic confinement fusion, and from what I can tell, its paying off. I know people who work at LLNL on the NIF project, and despite lab managemental scandles, its coming along quite well. So what's your feeling towards intertial confinement based fusion? I know neither method will amount towards a fusion powerplant for at least another decade (2010 by LLNL projections in NIF design stage, far to optimistic), but ICF in NIF and its predicessor projects (ie, NOVA) worked amazingly well. I always here about the Tokamak failures, so how is ICF works then MCF, and how will ICF pan out?
That was Marge Simpson scolding Lisa for building a perpetual motion machine.
So it looks technically feasible after all. Since the first experiments most people have been thinking you can't get more out of fusion than you put into it. It's interesting since the physical laws behind fusion power aren't exactly known and thus it isn't really possible to prove how much is the theoretical maximum that fusion can deliver. We can look at the sun for one example, but you can't have a power plant that big on Earth. (The same goes for superconductivity, no one knows whether it's possible to achieve under room temperature)
Maybe now the scientists can get some real funding out of their governments... after the cold war projects that require huge amounts of effort like the creation of the nuclear bomb and moon travel have been kinda gone. I wonder what the world would be like if the soviet union hadn't collapsed and flexing of the superpower's muscles had poured in the same amounts of money into science that they did 50 years ago...
Exactly how would clustering fusion reactors that don't give out more energy than is put in help? Power plants in general are more efficient the bigger they are.
For instance, people keep whining about electric cars with the argument that the energy must be produced elsewhere and that makes pollution - but the power that is lost in transmission of the energy is easily gained by the increase of efficiency when using huge power plants instead of a small one in every car.
Energy production just isn't the same as computer power. Computers become less effective when they get hot, power plants get more effective :) This is a fundamental law of thermodynamics.
It seems that if current expiremental reactors are producing just more energy than is put in (say maybe 1.1x), this new reactor will produce four times the energy (4.4x) with a net energy gain of ((4.4-1)/(1.1-1)) or 34 times more usable output energy. This seems like a pretty major breakthrough.
-- Too lazy to get a lower UID.
As one of the aforementioned "evull oilmen" I'd like to ask, if Bush etc. are so corrupted by the oil industry, why do they stress nuclear fission power su much in their energy plan?
I mean, it's a nice theory, but the realities of nuclear power's potential (instead of the if-we-use-it-we're-going-to-die crowd) and the fact that he's pushing it suggest otherwise.
Finally, if fission can't be made safe, what makes you think they'll allow fusion? The reactor walls get radioactive, which causes a fairly long-lived waste problem by itself. What's the point in developing fusion if we can't even deal with fission, which is a much simpler system?
(currently testing something about signatures here)
Yes, I concur. Way back when I was doing some research projects on Ball Lightning, it appeared that Koloc's model was the only one that was matching the reports I got. Especially the one where... hmm... maybe I should save that detail for the patent application.
Seriously, I like Koloc's idea a lot, and wonder what he could do with more funding.
(currently testing something about signatures here)
Tritium has a half-life of somewhere around a dozen years; one of the decay paths is to Helium-3. So you can make Tritium into Helium 3 just by waiting.
(currently testing something about signatures here)
Except solar power isn't free; there's the cost and amortization of the solar cells to consider.
PS: I'm having trouble getting to new scientist's site. Any alternative sources of this news?
(currently testing something about signatures here)
Actually, the main political problem with SPS is that we don't have cheap launch vehicles. Which is, IMHO, a problem of political origin.
(currently testing something about signatures here)
On the other hand, these people are "old money". Their families (and their family's lawyers and portfolio managers) didn't get that way thinking short term.
maybe they can make them small enough to power my Honda!
These are my friends, See how they glisten. See this one shine, how he smiles in the light.
You get more energy than you put into it but it does require fuel to generate more energy.
Think of it like a car. A spark is required to ignite the gasoline but more energy is release in the combustion of the gasoline than the spark provided.
I'm just guessing here.. But wouldn't a failure in one of these things most likely be in the magnetic containment?
100M degree Kelvin plasma would melt through the walls of the reactor real quick once a section of the magnetic field collapsed. And probably squirt out and melt anything nearby.
Since it's hydrogen fusion there wouldn't be any highly radioactive elements. Helium and possibly Beryllium (sp?) isotopes, nothing like plutonium. So cleanup wouldn't be that bad I suppose.
Anyway, I just wonder how damaging a containment failure would be on a full sized reactor.. a 6 inch hole in the reactor and things up to 5 feet away melted.. Or everything within a mile vaporized?
has done that for almost 20 years, produce energy significantly in excess of what they're putting in! But they had a lot of problems... Only 4 reactors/generators like this could give enough power to the whole country!
<rip>
A breeder, or fast, reactor is designed to produce both power and new fuel at the same time. Breeder reactors do away with the moderator so that the neutrons retain higher velocity and kinetic energy. When these neutrons are captured by U-238, which is nonfissionable, they can convert it into a transuranic element, known as plutonium-239 (Pu-239), which is fissionable. This new fuel can be separated out after generation in a reactor for use as fuel in other reactors. Since U-238 is much more plentiful than naturally occurring U-235, the development of breeder reactors may bring a long-lasting nuclear fuel supply.
The small EBR-1 breeder reactor first produced electric power in the United States in 1952. Other breeder reactors have since been developed in the United States, France, Germany, Italy, the United Kingdom, Japan, Russia, and India. The world's only operating commercial plant is the Super-Phoenix, a fast-breeder reactor in France.
</rip>
--
"Science will win because it works." - Stephen Hawking
Probably takes them in a car, too.
Are there any fusion protest groups yet?
Against the National Ignition Facility
"Friends of the Earth" Europe say: "The commercial use of nuclear fusion is pure fantasy. Already 25 years ago the same people had predicted that in 50 years fusion would be a viable energy resource, but it seems like we are always 50 years away from fusion becoming economic. The European Council has to stop this waste of millions of taxpayers money."
Green groups say Fusion is a Scam
"Friends" of the Earth wants to "Terminate existing tokamak reactors, cancel construction of the similar spherical torus reactor, and adhere to a withdrawal from the International Thermonuclear Experimental Reactor (ITER) program."
Sierra Club The dangers posed by the probable releases of tritium used by fusion plants, the problems with decommissioning these plants, and their high costs lead the Sierra Club to believe that the development of fusion reactors to generate electricity should not be pursued at this time.
In other words, either we get cheap, clean, nearly free unlimited energy, or our future is gonna look uncomfortably like those Mad Max movies.
"How many light bulbs does it take to change a person?" --BMcC-->
As well you shouldn't! :P
The enemies of Democracy are
It's hardly worthless, just less informative than it could be. There is enough information to conclude that they more than broke even.
First, previous research broke even but could not get much past that. This new technique produces four times as much fusion, but uses a very small amount of additional energy. Qualitatively, that is enough to conclude that it is well past breaking even.
The enemies of Democracy are
since aquiring another neutron would make U-238 into U-239, NOT Pu-239. Unless the article meant protons, but I wouldn't believe anything someone says about fission if they can't keep neutrons and protons straight.
The enemies of Democracy are
Good idea.<P>
But, well, the fusion guy's problem was solved.
What about the AI character's problem?
(slightly offtopic)
:)
That's interesting, especially considering that here in Quebec pretty much all electricity is provided by a Crown corporation called Hydro Quebec, its basically a monopoly and the company is run by the government, but in Quebec we have some of the cheapest and most reliable electricity in the world, we actually WAY more than we can use, and we sell ALOT of it to Ontario and the US.
One thing that I have thought about, is that we have way more than we can possibly use, and that's AFTER losing more than 80% of it in transit, imagine what room-temperature superconductivity could do, we could run 1 cable from here to California and take care of their energy problems for good, at the same time as becoming the richest province in Canada
Actually, Jupiter does have a small fusion reaction going on inside it, it gives off about the same amount of light as it reflects from the sun, so the Jupiter we see in the sky is about twice as bright as it should be.
I think they're scared that they may become irrelevant. I mean, when's the last time you heard environmentalists complain about the cost of a plan or research?
Waiting isn't that much of a problem when it's 10 or 5 minute intervals in the city. Also cars may take you from A exactly to B, but the convenience is gone when you can't park your car anywhere near B.
But in the US it's a different matter. Cities aren't as dense: distances are larger, good coverage with public transit is harder, more parking space.
So what you propose is to use lots of electric power to accelerate particles, and then turn the particles' kinetic energy into electricity. Why not just cut out the particles and use the electricity directly, since you have it anyway?
It already is working. Didn't you see The Saint? It can explode light bulbs and send cool light effects into the sky!
Oh, my god!
You're so wrong. The energy production of fusion (and fission for that matter) comes from the difference of the bonding energy of the nuclei before and after the reaction. The helium's is lower than the two deuterium's. The difference if radiated in form of photons.
Go back to your books, because knowledge really rules.
Szo
Red Leader Standing By!
From that url: What is Fusion?
:)
Fusion is combining the nuclei of light elements to form a heavier element.
This is a nuclear reaction and results in the release of large amounts of energy!In a fusion reaction, the total mass of the resultant nuclei is slightly less than the total mass of the original particles. An example can be seen in the Deuterium-Tritium Fusion Reaction. This deuterium-tritium fusion reaction results in an energy gain of about 450:1. This difference is converted to energy as described by Einstein's famous equation, E=mc^2 Deuterium and tritium are both isotopes of hydrogen. Deuterium occurs naturally in nature - about one part in 6000 is found in ordinary water. Tritium can be produced from lithium.
Now please tell me, how is it different from what I just said, and where is the radiated neutron?! Study some physics, it won't hurt you. I know, I did it
Szo
Red Leader Standing By!
Smarter Hydrogen? What's next? Intelligent Methane? *brrrap* 'scuse me.
Perhaps... Heat Pollution would become a problem, but hopefully that would be worse than greenhouse-effect causing gasses that we release by Fossile fuels, if such gasses do in fact cause global warming (of which I'm not fully convinced.)
Getting rid of excess heat is easy enough if you decide to spend the money to do it - just set up a solar heat plant, point the mirrors at a patch of empty sky, and run it in reverse (use a heat exchanger to heat the working fluid from your waste heat, run it through the pipes in the mirror array, and let it beam its blackbody radiation out into space).
Yes, it takes a fair bit of power to move heat across this big a temperature differential (you need to heat the pipes up until they're glowing orange to get a decent rate of heat transfer). However, you'd only need to do it in the first place if you had power to burn.
To prevent confused responses - you're not building a giant toaster-oven. The heat you're stuffing into the pipes comes from the city or industrial park you want to cool off, via heat exchanger. You're not generating it from scratch.
The downsides are that the D/He-3 reaction has a higher energy threshold, so it requires a better confined plasma to make D/He-3 energy production plausible. Also, the supplies of He-3 on Earth are limited. Of course this disadvantages leads to a interesting convergence of interest between fusion research and space exploration. There's plenty of He-3 (deposited from the solar wind) on the moon. So He-3 mining could be powerful reason to maintain a base on the moon.
I'd understood that He3 was one of the decay products that you get from neutron irradiation of a fusion reactor's lithium blanket. A few other articles that I'd read claimed that this was the main reason a lithium blanket was used (the idea was that a H2/H3 plasma fusing would transmute enough of the blanket into He3 to provide H2/He3 burning for power generation).
Is this still a viable option, or has it been shown to be impractical?
Let that stream of plasma impact some new magnetic fields. It will push on the field lines, imparting momentum to them. This could accelerate the magnets generating those lines, even if they were on the other side of the wall. If those magnets were attached to wheels, could you actually make a "magnetic turbine", directly converting the kinetic energy of the plasma into mechanical work?
...'94? '95? can't remember) :).
Maybe a real physicist can enlighten me... Is this possible?
I'm not a real physicist either, but I faked being one well enough to get a free vacation out of it (IPhO
It turns out that you can get electrical power directly from a plasma stream by the Hall effect (similar to what you describe). Fire a stream of plasma through a magnetic field that's perpendicular to the direction of plasma motion, and you'll get negative charges deflected one way and positive charges deflected another way. Put electrodes beside the plasma stream to collect the charge, and you have a power source. Look up "magnetohydrodynamic generators" in your favourite encyclopedia for more information.
As for fusion plants, the best approach to tapping power that I've heard of is to put a big block of lead or concrete around the reactor, let it heat up from absorbing gamma rays and other crud coming out of the plasma, and run steam turbines off of it.
Current fusion engineering designs call for deuterium and tritium to be used as the fuel. You can easily get a virtually inexhaustible supply of deuterium from seawater. Tritium is another matter altogether. The only source available for this is fission reactors.
A fusion reactor would produce more than enough neutrons to breed tritium (and hopefully helium-3 as well).
And don't forget the other things that are petroleum based - the industrial chemical industry , the plastics industry, and the fertilizer industry to name a few - when oil gets scarce (coming soon) everythings gets expensive.
Plastics can be produced from anything hydrocarbon-based. You can already do it easily from plant matter - petroleum just happens to be cheaper for the time being. Ditto most organic chemicals used in industry. Most fertilizers that I know of are based on minerals, not petroleum (a fertilizer provides mostly nitrogen, phosphorus, and potassium to plants, none of which petroleum is terribly rich in; typical fertilizers are based ammonium nitrate, potassium nitrate, or pick-a-random-phosephate, if I understand correctly).
Nothing that oil fields are vital for.
No, they won't. If energy becomed more expensive, people would just return to nuclear power. If you think that people are going to resign from driving, driers and air-conditioners, you're insane.
If it's forced on them incrementally, I think they might. Especially since the alternative with or without fusion power is to have an Evil Nuclear Plant right next to their city (fusion isn't much cleaner than fission for low-level waste).
It's a case of foolishness (hopefully) defeating foolishness.
Please, do not use all the water in the oceans just for fueling the fusion in those power plants... We (mankind) need it as long as we want to actually LIVE on this planet...
You'd only need to take the deuterium for the first million years. Removing 1/7000 of the oceans' water would not cause substantial problems.
Pretty interesting idea. But that patch of empty sky is actually full of a lot of air. The heat has to pass through a lot of air before it gets free in space. Since conduction and convection are much more effective than radiation at transmitting heat, wouldn't you just end up making your local chunk of the atmosphere very warm?
:). As you raise the temperature, radiative cooling starts to dominate (transfer by conduction goes up linearly with the temperature difference).
Heat lost by radiation goes up as the fourth power of temperature - this is why you'd have the coolant hot enough to glow orange
If I understand correctly, the atmosphere's pretty good at blocking light in the thermal IR band, but you can see by example that visible and near-visible passes through quite easily - most of the sunlight shining on earth reaches the ground.
Heat the coolant up to a thousand degrees centigrade or so, and most of its emission will be in visible and near-IR (thermal IR is the band that objects at room temperature shine in).
Now, a week of cloudy days would make this system less effective, but you could get around that by using a nearby lake for heat storage until the sky clears again (though that won't be very nice for the inhabitants of the lake).
Bottom line, if someone can come up with a cheap/light way to store electricity (either through a flywheel or through a superconducting coil), we'll still keep boosting my Exxon stock. And we'll do it by drilling in your backyard.
Fuel cells for cell phones should be appearing within the next 2-5 years or so. Prototypes already exist, and energy density is almost as good as a chemical fuel.
Fuel cells at present are a pain for things like cars because storing the hydrogen they use is very annoying (it's nowhere near as dense as a liquid). However, fuel cells that can process methanol are buildable, and will IMO probably be what brings fuel cell cars into the real world. Or you could just pump methanol into an interal combustion engine made of ceramics or otherwise made corrosion-resistant.
Methanol can't be easily produced by "recharging" fuel cells (unlike hydrogen), but you can make it by fermenting plants or by direct synthesis (burn CO2 incompletely in a hydrogen atmosphere and use fractional distillation on the combustion products).
In summary, power storage won't be a problem for long.
anyone with a tenth of an IQ point knows that fusion is clean and safe, unlike fission.
Fusion is certainly safer than fission from a high-level waste point of view, but how exactly do you propose to prevent the reactor vessel from becoming radioactive? Even "relatively few" neutrons is enough to cause major headaches for disposal of replaced parts for a multi-gigawatt reactor.
Claiming that it's perfectly clean will only make backlash worse when the public finally clues in. Remember when fission power was supposed to be safe and clean?
What about the supply of deuterium? It's not perpetual...
It's close enough to perpetual that it makes no difference.
About 1 hydrogen atom in 7000 is deuterium. Hydrogen accounts for 1/9th the mass of water, which means that the mass of deuterium we could extract from the oceans is about 1/63000th the mass of the oceans.
Assuming an average depth of about 3km and a coverage of 2/3 of the Earth's surface, you have about 1e18 tonnes of water on the planet. Let's say 1e-5 of that is deuterium that you can easily extract, and you get 1e13 tonnes of deuterium.
Fusion is about 1% efficient at turning mass into energy. Let's say that your fusion reactor is 0.01% efficient in total (pessimistic estimate). This gives about 1e13 J/kg, or 1e16 J/tonne.
The total amount of energy we could extract from fusing the oceans' deuterium with these fairly inefficient fusion plants is about 1e29 J.
If we want our fuel supply to last a million years, that gives a world power consumption of 3e15 watts. Far, far more than we consume now.
If, within the next million years, we build reactors good enough to fuse light hydrogen, we'll have enough fuel to last us until the sun burns out (several billion years). Or we could just ship in deuterium from elsewhere in the solar system. Either way, barring a *huge* population expansion, we won't run out of power - ever.
In other words, either we get cheap, clean, nearly free unlimited energy, or our future is gonna look uncomfortably like those Mad Max movies.
Actually, what would be more likely to happen is a slow and painful shift to renewable forms of energy and a lifestyle that consumes less power.
Fossil fuels won't run out all at once - they'll get incrementally more expensive as they become scarcer and more difficult to extract. As price climbs, people will out of necessity start using less power, and alternative forms of power generation will become cost-competitive (even if their own cost doesn't change).
You'll see more houses with photocell shingles. You'll see a mirror-based heat plant or a wind farm next to most cities. More people will take public transit, because it's cheaper than driving. House design will depend more on passive heating/cooling and good insulation than on furnaces and air conditioners (they'll still be used; just on lower settings). People will have to hang-dry their clothes instead of tossing them in the drier. And so forth.
A Mad Max style catastrophy would only happen if energy supplies ran out all at once. A nuclear war or an asteroid strike could cause this, but I doubt fossil fuel problems will.
ok, so you have this plasma "floating" in the bottle at 12 gazillion degrees. the power goes out. doesn't your ball of plasma just eat it's way through anything it touches and head towards the center of the earth?
The plasma is very hot, but also very tenuous. You might have a few thousanths of a gram of matter in the reactor. As soon as this touches the reactor wall, it cools down to room temperature. Your reactor wall gets warm. That's about it.
Also, as your plasma is much less dense than air, if anything, a ball of plasma would rise.
You'd never get a ball. What happens is that as the containment field weakens, the donut-shaped mass of plasma expands until it touches the side of the container. In theory, if you had a "hole" in the containment field instead of the whole thing weakening, you could get a jet of what looks like flame, but this is next to impossible to do even if you're _trying_. The natural shape of the field is more-or-less uniform.
Plasma is just a hot, conducting gas. It follows gas law like everything else.
This site gives a general overview of current fusion studies.
For the more technically inclined, you can check out the journal Fusion Engineering and Design (Sorry - if the link doesn't work for you, it's probably a pay-per-access journal and your business/school/self isn't a subscriber). Anyway, it's full of juicy fusion engineering and design details.
Repeat after me: Flux Capacitor,
Mr. Fusion never seemed any better, to me at least, than a really expensive Ronco Food-Dehydator....
signal, noise, to me it's all the same.
1.21 would be the correct.
signal, noise, to me it's all the same.
The byproducts of fusion are excess neutrons that
convert any materials around them into dangerous
radioactive isotopes. Fission reactors have
internal shields to capture execess neutrons,
but none of the fusin designs have such yet.
He-3 may be a possible outcome of neutron reactions with Lithium, but I think the main product is tritium. Anyway, in order to have enough neutrons around to react with a lithium blanket, than you lose have toone of the advantages of D/He-3 - fewer neutrons. Anyway, I may be recalling this incorrectly, but I don't think that you expect to get much He-3 from a lithium blanket.
...
--
I hope we shall crush in its birth the aristocracy of our monied corporations
And I'd be a Libertarian, if they weren't all a bunch of tax-dodging professional whiners.
Berke Breathed
Well, if the fusion reactor uses D/He-3 fusion mentioned elsewhere in commments here) instead of D/T, then it is possible to avoid the steam cycle. D/He-3 reactions yields a proton (instead of a neutron) as one of the products. The electrical charge of the proton can be used to trap its energy electrical, and avoid the step of heating water.
...
--
I hope we shall crush in its birth the aristocracy of our monied corporations
And I'd be a Libertarian, if they weren't all a bunch of tax-dodging professional whiners.
Berke Breathed
The downsides are that the D/He-3 reaction has a higher energy threshold, so it requires a better confined plasma to make D/He-3 energy production plausible. Also, the supplies of He-3 on Earth are limited. Of course this disadvantages leads to a interesting convergence of interest between fusion research and space exploration. There's plenty of He-3 (deposited from the solar wind) on the moon. So He-3 mining could be powerful reason to maintain a base on the moon.
...
--
I hope we shall crush in its birth the aristocracy of our monied corporations
And I'd be a Libertarian, if they weren't all a bunch of tax-dodging professional whiners.
Berke Breathed
Why the hell are we working on making our own self contained fusion reactions when we have the solar system's largest self sustaining fusion reaction going on not 93 million miles away?
99.99999% of the sun's energy output flows, wasted, into the interstellar depths. A tiny fraction of this energy falls on our planet's surface and is used by us (either in stored form as fossil fuels, or more or less directly as solar, wind, etc...)
Ultimately the only real solution to our energy woes lies in figuring out how to catch just a little extra sunlight, convert it into usable forms of energy and move it to the Earth's surface.
Solar satellites are the answer. We have the technology now. We know how to make it work now. People have been designing complete, workable systems that use nothing more than existing technology for the last quarter century. Why aren't we funding them instead of this pie in the sky "always another two decades off" technology.
Certainly our skills in manipulating hot plasmas will eventually reach the point where a Fusion plant will become feasible. But by that time we could have built and launched an entire fleet of solar satellites, or paved over every major desert with solar tiles or reflecting concentrators.
-josh
In the worst case, it already is safer, though - a catastrophic failure might destroy the neighborhood, but there shouldn't be any lingering radiation to harm future generations. Whereas Chernobyl will probably be making reindeer sick for hundreds of years (or until we find a perfect and everlasting containment system). So use the best safety devices (because these plants are expensive to replace) but also build them out in the desert somewhere, or in orbit.
Your right to not believe: Americans United for Separation of Church and
The orbit thing was just off the top of my head. I imagine you could use microwave transmission to do it. Of course, then your microwave receivers have to be out in the desert somewhere, so why not just put the fusion plant there in the first place...
Your right to not believe: Americans United for Separation of Church and
Well, except for the heat and the radiation, possibly. OTOH, I'm not sure that intense magnetic fields over long periods of time are all that safe, either.... Wasn't there something about that encouraging cancer?
Caution: Now approaching the (technological) singularity.
I think we've pushed this "anyone can grow up to be president" thing too far.
OK, I'm not a physicist, but the ideal gas law is certainly not for incompressible gases. The very presence of the volume term in the equation explicitly takes into acount the compression of gases. It is generally liquids that are incompressible.
Even if it does not strictly apply, it does give some idea how high temperatures and high pressures are related and how tempurature drops when high pressures are released by the loss of containment. I expect that electrostatic repulsion of ions in a plasma would only increase the drop in temperature from the loss of containment.
I have discovered a truly marvelous sig, unfortunately the sig limit is too small to contain i
ok, so you have this plasma "floating" in the bottle at 12 gazillion degrees. the power goes out. doesn't your ball of plasma just eat it's way through anything it touches and head towards the center of the earth?
No. The only thing keeping the temperature high is the containment. If the containment is lost, the fusion stops (and the net energy output stops) and the plasma expands and cools.
Exercise for the student: Review the ideal gas law (PV=nRT) and calculate the temperature of a 1 million degree plasma as it expands from a volume of 1 m^3 to 10^3 m^3 and reduces in pressure from 3 million atmospheres to 1 atmosphere.
I have discovered a truly marvelous sig, unfortunately the sig limit is too small to contain i
I just copied the (nuclear) plant we have now. Then, I added some fins to lower wind resistance. And this racing stripe here I feel is pretty sharp.
--Homer Simpson
--
--
"Outlook not so good." That magic 8-ball knows everything! I'll ask about Exchange Server next.
If I remember from High School, there's enough Deuterium in the earth's oceans to last thousands and thousands of years at our current growth rate if fusion becomes feasable.
Of course, my High School physics class was a long time ago in a city far far away so I could wrong.
I am not a physicist, this is just my understanding of the process.
The fusion reaction stops, since the pressure provided by the containment is necessary to maintain the reaction. As the poster below mentions, if the plasma ate through the torus, I imagine some radiation would be released between the time containment was lost and the plasma fell below reaction temprature.
The problem with fusion reactors seems to be the opposite of fission. That is the problem is not keeping the reaction below melt-down level. The problem is keeping it fast enough so that enough energy is produced to sustain the reaction. Therefore, I don't think a failure in a fusion reactor would produce a "China Syndrome" or anything like that.
BMW showcases cars that run on hydrogen
BMW officials traveled to one of the nation's smoggiest cities to show off a fleet of luxury cars that run on rocket fuel, but belch virtually nothing more than water and steam from their tailpipes.
Company officials said Thursday that the hydrogen-powered cars are an important step in weaning the automotive industry from the oil that has nurtured it since the internal combustion engine first powered automobiles in the late 1800s.
cpeterso
Where in the article does it say they've made a scale model produce more energy than they're putting in? They haven't; they've just overcome one obstacle, out of many.
They found a new method of enhancing plasma containment, and they've tested it, and it works... it in no way means they produce more energy than they use; the second they do that, we're in the fusion business... even if it's a very small margin.
The article actually says nothing about getting an excess of power out of anything.... other than stating that hitting the 'break-even' point is the current goal of fusion research.
Dunno where they got that terribly misleading statement from.
You are right; as soon as we have a power excess, we're in business.
Now, imagine the reaction to beaming power down to a rectenna using microwave radiation. As soon as the word "radiation" gets mentioned, expect people to go ballistic.
If you beam power down via infrared laser, you'll get "death beam" cries.
The REAL problem with the whole situation is the massive level of scientific illiteracy. . .
Well, Hot fusion, cold fusion...as long as there is fusion, I'm all for it...I just hope that it doesn't create ungodly amounts of EMF fields and reset everyone's palm pilots. :)
JoeLinux
Kill -9 'em all, let root@localhost sort 'em out.
Screw the children. I was thinking about myself.
-B
With a fission reactor, if there is a problem, you drop the control rods and everything comes to a halt.
With a fusion reactor, what would happen if you completely lost power to the magnetic fields? Would it blow up like a H-bomb or at least level the building? People aren't going to allow these kinds of plants to be built unless they are as safe or safer than fission plants.
-B
Geez, trying to give a simple explanation, you right, the average nuke would be a bit much, but it gives the average person a good image of a quick large burst of energy.
Actually no the containment is fairly energy cheap, the real problem is the startup energy versus the energy it creates. Basically to start a fusion reaction you basically need a huge energy burst, essentially a nuke. But small fusion reactors do not give off even the amount of energy of a nuke, so you actually used more energy to start the reaction than you got out of it. Then you have very large reactors like the sun, which while its very energy expensive to start, it virtually last forever and the ratio of start energy to output is very good. But the problem is figuring out how to contain a large reactor, and this is a way that has been proposed of containing a reaction that is large enough to give a positive output versus input.
Actually I wasn't quite telling you the whole story, while the size thing is true, also you can have a smaller container that "burns" much hotter, which will also produce a positive output, containing that is a different type of challenge, and that is the aim the MFC it appears. Sorry I really didn't get a chance to read the article as its highly slashdotted, and my brain much have been elsewhere :(
Actually, The script said "Gigawatts," it's just that nobody knew how to pronounce Giga back then. Funny, huh. (Funny if you're a geek, I guess. At least, it's funny to me.)
Q: What's a Serway?
A: Oh, about 175 pounds.
www.timcoleman.com is a total waste of your time. Never go there.
I remember reading a while back (2 years+?) that the Tokamok reactor had generated it's first power in a microsecond burst or something, and I think that was the first power generated by a controlled fusion reaction.
Then I heard nothing. I kind of thought we were moving into an area of engineering improvement with fusion, meaning the major problems were solved and we were just trying to figure out how to make it feasible. I guess that isn't the case.
Does anyone have any good links for the state of fusion research?
Thanks.
In fact, the rate at which man is using primary energy is about 1/10,000th the rate at which solar energy is hitting the earth. Four orders of magnitude, not eight.
Sheesh.
Farnsworth achieved fusion in the sense that his device produced fusion reactions, emitting neutrons. It did NOT achieve anywhere close to breakeven. Noone has ever achieved close to breakeven in an electrostatic device of the kind he proposed, and there's good reason to think it would be hard.
Achieving fusion reactions is *easy*. Anyone can do it with some deuterium and some electrodes in a discharge tube with a very high voltage power supply. This was first done in the lab in the 1930s. Heck, the 'Amateur Scientist' column in Scientific American showed how the layman could do it decades ago. The hard part is achieving breakeven, which these simple basement schemes cannot do.
> Also, fusion will be MUCH cheaper than gasoline.
This is nonsense. Fusion promises to be very expensive. Oh, sure, *deuterium* is cheap, but deuterium by itself isn't useful. You need this big expensive reactor to get energy from it.
This kind of economic illiteracy shows up often in naive talk about energy. Sunlight is free, wind is free, does that make electricity generated from these sources free? Of course not.
You do get 3He from the decay of tritium produced in the blanket of a DT fusion reactor.
However, most of the tritium produced in that blanket has to be recycled back as fuel for the DT reactor. The net reaction is D + 6Li --> 2 4He. To make 3He you need extra neutrons from (n,2n) side reactions. As a result, the 3He output will only be a sideshow, a minor byproduct of an energy system that produces most of its energy from DT reactions.
To have a system that is primarly D3He fueled, you need to be able to mine 3He somewhere. The moon has been suggested (but at 10 ppb the economics are dubious). Beyond that, Uranus may be a good source, and maybe we can mine 3He from the thin atmosphere of some as-yet undiscovered Kuiper Belt Object. A body the density of Pluto with a radius of ~2800 km and a temperature of 30K could retain 3He in its atmosphere. It would be about 3% of the mass of the Earth, about half the mass of Mars.
No, the energy spent in the magnets is not what keeps fusion reactors from reaching breakeven. What keeps them from reaching breakeven is the distressing tendency for the energy to leak out of the plasma. BTW, this is also why fusion reactors tend to be big -- energy escapes less readily from a larger plasma.
> Basically to start a fusion reaction you
> basically need a huge energy burst, essentially
> a nuke.
Basically, you're full of shit. That statement is completely wrong. The energy content of the plasma in a fusion reactor will be measured in megajoules, not the terajoules of even a small nuclear weapon.
Check with the military. I shared a lot of upper-division/graduate physics and math classes with officers at the Orlando Naval Training Center (now closed, iirc). I can't remember if they were on the nuclear officer track, or already certified and in Orlando to train recruits.
Anyway, they knew how something about naval propulsion with nuclear-fired steam turbines. I made the mistake of making some comment about the "steam" coming from the tea kettle one time, and got a quick lecture on what happens when superheated steam hits human flesh. It's not pretty.
For every complex problem there is an answer that is clear, simple, and wrong. -- H L Mencken
So how would you convert the energy produced into electricity?
Steam turbines might seem archaic, but they're still used for the simple reasons that they're a well-proven technology and high pressure steam contains a *lot* more energy per unit volume than pretty much anything else in routine use. (After whatever heats the water in the first place, of course!)
Remember, the plume of vapor over your tea kettle on the stove is not steam. It's water vapor condensed from a very small amount of steam. Steam is invisible, and tends to do things like fling heavy fighter aircraft off of flight decks or instantly cut people in half if they walk in front of a pinhole leak.
For every complex problem there is an answer that is clear, simple, and wrong. -- H L Mencken
Now that they spin the plasma in the tokamak, would it be possible and make sense to let collide two counterrotating 'donuts'?
Perhaps so that the point(s) of collision stay at the same place?
Just curious
chess
Well to build it you also need an atomic vector plotter and a Bamberweenie 57 Sub-Meson brain, if I am not mistaken. Then you need a Golden Bail to make it operational, but the finite improbability generator should take care of that.
if ($it != $onething) {$it = $another;}
a) One couldn't get his AI beyond the three-year-old level. It was blazingly fast, but refused to mature.
b) The other couldn't get his torus to manipulate its magnetic fields fast enough to maintain the fusion.
Sound familiar? Of course, the solution was simple: The AI guy handed off his project to the fusion guy, and overnight the problem was solved! When toddlers try to eat something they don't like, they push it around with their tongue and teeth and try to swallow without letting it touch the sides of their mouth...so he put the AI in charge of the fields and programmed it to hate the taste of plasma!!
God, I miss that mag. I should look into a subscription...
------------------------
Co-founder of GerbilMechs
Here are my papers.
"Simultaneous Electron Density and Ion Temperature Measurements of a Moderately Dense Plasma Using Doppler and Stark Broadened He-II Lines" (with others), Applied Optics (Letters) v 17, p1481, 1978.
"High Temperature, High Density Plasma Production by Vortex Ring Compression" (with others), Physical Review Letters, v 41 #3, p166, 1978. "
The Interaction between Two Force Free Plasma Vortices in the TRISOPS III Machine" (with others), Physics of Fluids, v 22, p379, 1979.
There are other Trisops papers, but I do not have the references here at work.
I do not have references to the Plasmak work.
My understanding of ITER, is that even on paper they did not solve the first wall problem, and with a diverter heat load of 1-20 MWatts/M**2
I post this as a former fusion researcher and a former project manager for the Office of Fusion Energy (OFE) of the Department of Energy (DOE)
Many decades ago the international fusion community put all of its chips on the Tokamak. It has been a disaster.
Even if a Tokamak could produce break-even fusion ( getting more energy out than you put in) the engineering obstacles to creating an economically successful reactor are daunting.
Many years ago, the OFE sponsored a study, Project Aries, of the costs of a Tokamak reactor. Even using the usual optimistic assumptions, the cost came in way above solar and wind power, let alone fossil fuels.
Another symptom of the problem is that three times in a row, projects to build larger Tokamak have collapsed in the design stage. That is, even before anything was build, none could come up with a working design. The International Thermonuclear Experimental Reactor (ITER), the latest attempt, collapsed as the price tag spiraled above $20 billion (US)
The whole OFE degenerated into a "you scratch my back and I'll scratch yours" process where the lab directories divvied up the pie. All non-Tokamak ideas were cut off, including the one I worked on.( more below).Congress cut the OFE budget almost in half a few years ago in response to this.
That being said, I respect the findings of the DIII-D team. The DIII-D is very well run research project, the their accomplishment is to be applauded. Now for a blatant plug. In the 70s I worked on a small project at the University of Miami, the Trisops project, which was defunded. The amount of money was not an issues ( our request was quite small), but the non-Tokamak nature, and the nerve of the principal investigator, Dan Wells, to point out that the Tokamac was unworkable.
The Trisops machine was recently moved from the University of Miami, to Lanham Md, with a small NASA grant, but there is not money to run it. You can see a report on it.
Another interesting project, the Plasmak(TM) project that is being run by Paul Koloc ( out of his garage!!).
The holy grail on fusion research is a stable plasma structure. The Trisops project achieved it one way. Paul has noted that ball lightning, which has been known for millennia, is a stable plasma structure. He has machine that produces ball lightning, and is measuring it. He gets no DOE funding of course.
I work at princeton plasma physics laboratory in the computational plasma physics group. Politics have jack shit to do with why we don't have fusion working. The fact that plasmas are goddamned hard to model and understand and maintain stably ARE why we haven't gotten fusion energy yet. We get PILES of USDOE funding every year and pour it into more and more innovative research. No one is standing out picketing plasma research labs because anyone with a tenth of an IQ point knows that fusion is clean and safe, unlike fission. In summary: pull your foot out of your mouth and your head out of your ass, and talk about something you know.
Plasma looks a lot like hot grits, I understand
A higher dependency on Solar Cells and heat-energy-converting/trapping devices could also help lower the amount of heat we have to deal with.
(By "heat-energy-converting/trapping" devices I presume you mean solar water heaters and the like.)
Solar is NOT a solution to "global warming". That's because solar panels capture nearly all the incoming radiant energy. Solar cells convert a few percent to electricity (that ends up as heat when it's used) and the rest to heat at the panel. Solar heaters just capture it and turn it into local heat.
The problem is that they replace something that reflected a significant part of the incident light still as LIGHT - at frequencies that pass right back through the greenhouse gasses. Dropping the albedo at the surface means you've boosted the greenhouse effect BIG time, without even touching the gas concentration.
Fortunately, global warming is NOT a big issue. As it stands it's you're talking raising the temperature a couple degrees a century. That's like moving your farm 50 miles south or a couple hundred feet down the hill. Big deal. TINY compared to the ongoing climatic cycle.
But it's doubly not a problem because it's a RISE in temperature. It's TRIVIAL to drop the temperature by tens of degrees: Just inject a few tons of dust into the upper atmosphere - like volcanos do from timt to time. Inject as much dust as you need to get the cooling you want, and if you overdo it a little bit most of it will be down in a year or so - so just reduce the amount you're injecting until you get the temperature where you want it.
Now if it were global COOLING we were worried about - like the return of the ice ages - that might be an actual problem. (But we could just burn a LOT of fossil fuel and hold it off another few centuries, until we can put some moon-sized mirrors at L4 or L5 and solar-cook the planet as much as necessary.)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
If this were a production reactor, the question should be, is there a more efficient or cost effective method to get the power out than heat+water=turbine-power? I would guess the answer is not yet on the scale needed for a power plant.
It seems that the amount of energy spent in the magnetic containment fields is what is keeping fusion generators from reaching a breakeven point. Isn't it true that the superconductivity in high temperature superconductors can be maintained solely by the power needed to keep the conductors cold enough? Beyond that, it seems that the current in the coils can be as high as needed without further increases in power input. To reach breakeven one would theoretically only need to increase the plasma density. Is there something I don't know about plasma containment that continually depletes the magnetic fields?
Is there a fusion expert out there who can shed some light into the energy requirements of plasma containment?
At first I thought I might agree, but then I thought about what the reaction "products" were. IIRC, you get fast neutrons (high kinetic energy) and high-energy photons (gamma radiation). There is a kind of amusing simplicity in the strategy of letting these slam into some object, raising the average kinetic energy of the object's molecules (hence it's temperature), then extracting that energy from the other side. As others have pointed out, steam turbines are surprisingly efficient.
Are there materials that could be used for the gamma-ray equivalent of a photocell?
Given that neutrons have no electrical charge, is there any way to extract the kinetic energy other than smacking them into something?
Does a significant amount of the reaction output show up as "fast" helium? Is that any easier to deal with than neutrons?
We've been predicting that commercial fusion is only 20 years away for the last 30 years. Does this mean we can safely predict that commerical fusion is now only 10 years away...for the next 30 years?
Al.--
The Daily ACK - Eclectic posts by yet another hacker
This article just reminds me of the complete lack of direction the US has had for a long time in its energy policy. Bush has recognized this, but hasn't really proposed a solution.
Why on earth isn't US Energy Policy pushing hard for the development of fusion based technology? Isn't it obvious this should be the centerpiece of our effort? Unlike fission, fusion is clean, safe, sustainable, and environmentally friendly. It's just hard technically.
I believe the environmental movement has fallen into the trap of being against things, but not for anything. If you are worried about global warming, advocate fusion research.
Similarly, dependence on foreign oil is a great security risk and results in mideast leaders being a little to big for their britches. Iran, Iraq, etc... The mideast is extremely volatile and if it wasn't for oil, the US wouldn't have to care.
I'll see you guys on CNN!
I know it is theoretically the perfect power source, and that it shouldn't produce environmental problems like nuclear waste or dirty emission - but I also know as-sure-as-eggs-is-eggs that there is going to be a protest movement against it, regardless. Which leads me to my question...
Are there any fusion protest groups yet? I'm always late to join protest movements so I get crappy seating at rallies and never get to talk to the news media about my important opinions on the subject.
If you know of any, please post. If it helps, I am SINCERELY against the late 60's musical movement by the same name.
(signed, someone who genuinely wants to make a difference, as long as others are watching...)
I'd love to see a more indepth article on this. Most people I talk to don't believe me when I say that we've hit a breakeven point, and seeing this is refreshing. Its interesting, the plasma almost seems to be snagging on field imperfections, magnetic friction or something weird like that. Can anyone find a meatier version?
Slightly offtopic, but has anyone read the Night's Dawn Trilogy by Peter Hamilton? Earth was a rather nasty place due to heat pollution from fusion reactors...some funny comments on Chaos theory and weather too, an armada of butterflys...
http://thechubbyferret.net - Ferret pictures and informative links.
(Then our next problem will be heat pollution)
Perhaps... Heat Pollution would become a problem, but hopefully that would be worse than greenhouse-effect causing gasses that we release by Fossile fuels, if such gasses do in fact cause global warming (of which I'm not fully convinced.)
A higher dependency on Solar Cells and heat-energy-converting/trapping devices could also help lower the amount of heat we have to deal with.
And of course Trees help quite a bit, too. If would could just stop cutting them down.
"Everything you know is wrong. (And stupid.)"
"Everything you know is wrong. (And stupid.)"
Moderation Totals: Wrong=2, Stupid=3, Total=5.
Well, here's a little calculation that might help convince you about the greenhouse effect. I'm too lazy to look up the numbers and everything right now, but if you look in any basic astronomy book and this calculation should be there.
Take the luminosity of the sun and using the cross-sectional area of Earth and knowing Earth's distance from the sun, and accounting for it rotating for a more-even heat distribution, you can find the average solar power striking Earth.
Now assuming the Earth is in thermal equilibrium with it's surroundings, it will thermally radiate at this same power rate. Assuming Earth is a simple blackbody, what is the temperature that it radiates at? In other words, what is the temperature of the surface of Earth, as determined by the power of the sun and the distance from that sun?
The answer comes out to roughly (it's either a few degrees above or below this value) 0 degrees celcius. That is, around the freezing point of water. Granted some parts of Earth are frozen, but most parts are able to easily maintain liquid water, often at substantially higher temperatures than 0-degrees C. What accounts for Earth to be this warm? It's the greenhouse effect!
Most scientists will readily argue that the greenhouse effect is real, and in fact necessary, for life on the planet. So I hope that answers your question about the effects of greenhouse gases and global warming.
The real question, though, comes about when we consider how would the surface temperature change as we adjust the CO2 levels from what they were a hundred years ago. That's the harder question to answer.
I do believe that as a species, through engine emissions and other means, we are starting to significantly alter the planet's ecosystem. Probably through increased population alone will the effects start to manifest themselves. .V / _` (_-<_-<
.\_/\_/\__,_/__/__/
__ __ ____ _ ______
\ V
make world, not war
The Ice Ages were brief intervals. AFAIK throughout most of the last few hundred million years, anyhow, the Earth has been, if anything, warmer than it is now.
Hmmmm ... the description sounds all wrong.
... but the description is too vague to tell.)
...") if you don't in fact know what you are talking about.
I wonder about the scientific literacy around here when this comment is at a +5.
Most notably, particles don't helix around electric field lines. Particles helix around magnetic fields. This is high school physics people!
Now if I substitute electric for magnetic, the description makes a bit more sense. With this substitution, it sounds like the poster is describing a variant of a magnetic mirror machine.
This is so old it seems new.
(However, the variation might be original
At Livermore in the 1960s, a giant mirror machine was built and mothballed on the opening day (funding had dried up when the fusion community began its quest for mythical Tokamak fusion reactor). When I last saw the mirror building (three years ago or so), the equipment had been thoroughly picked over by experimenters.
Simple magnetic mirrors always had problems with the mirror loss-cone. Magnetic mirrors work really well except for particles travelling near normal to the current rings (the loss-cone).
Given that particles have to collide for fusion to occur, some collisions end up scattering particles into the loss-cone and thus, plasma confinement is not that great.
Also, the velocity space distribution functions resulting from a loss cone leads to a whole class of plasma instabilities (surprisingly known as "loss-cone instabilities").
More complicated mirror devices have been designed which allieviate some of these problems but they have not received much attention from funding organizations.
Please don't waste other people's time talking authoritatively ("Classical EM shows
Kevin
IANAP, so I am talking out my ass here, but it seems to me that the interior surface of the container of a reaction might just somehow be able to more directly collect energy, similar to the way solar-panels collect light. Of course, I have no idea what kind material might be used to accomplish this. How do solar-panels work? Silicon? Is it just dumb luck that the elements of a solar panel happen to convert light to energy, or is it a man-made composite, built specifically for that purpose?
... fusion reactor vessels will likely not be cheap).
... collisions ...). By that time, all that the sun radiates is a near perfect blackbody radiation spectrum.
Yes, you are talking out of your ass.
Note: I did my Ph.D work in plasma physics but now I work in quantum and optical electronics. I am probably one of the better qualified people here to answer your question.
Conventional fusion reactors fuse deuterium and tritium. Or, if you breed tritium from a lithium blanket surrounding the reaction, you can do fusion using deutrium-deutrium full burn (this is tougher to do than D-T reactions).
However, the by-products of D-T and D-D fusion are mostly high energy neutrons (and some gamma rays and neutrinos and alpha particles...). High energy neutrons are not easy to convert into electricity because neutrons are not charged. In fact, the neutron flux of a large fusion reactor would be deadly and thus a fusion reactor needs to be heavily shielded while operating. (Watch "Chain Reaction" and laugh as Keanu and his advisor walk around the operating reactor after it stabilizes.)
A typical approach for the conversion consists of letting your neutron flux heat a block of lead (or other material) and then running a standard steam cycle.
This sucks on many levels.
First, you end up throwing away much of your power from the inefficiency of the steam cycle. That is the theoretical thermodynamic efficiency of a fusion reactor which can somehow do direct conversion is effectively 100% (hot reservior at millions of degrees, cold reservior at room temp) while a steam cycle is limited by how hot you can heat your materials (hot reservior at thousands of degrees, cold reservior at room temp).
Second, the neutron flux will activate (i.e. make weakly radioactive) the walls of your reactor and steadily degrade the structural integrity of your vessel. As a result, current estimates are that the core of a fusion power plant will need to be replaced every couple of years (which makes energy providers frown
Other approaches are to use fusion reactors as breaders for fission plants (i.e. use fusion neutrons to enrich fission reactor fuel). Many estimates already put current reactor technology beyond breakeven for this type of design. However:
- Design is not politically feasible (some alternative fission fuel cycles might be possible). Fission suffers from NIMBY and fusion-fission breeders have a massive proliferation risk.
- Fuel for fission reactors is not particularly rare and running a fusion plant will likely not be cheap. Thus, economically, currently there is no compelling reason.
Solar cells on the other hand rely on photons exciting electron-hole pairs in a semiconductor. The light from the sun partially consists of photons in the visible and near infrared range which are suitable for conversion by a solar cell.
You might be wondering why fusion reactions produce high energy neutrons and gamma rays and other generally nasty things while our sun shines a whole lot of light. You should remember that the sun is big and the products of a fusion in the sun take hundreds of thousands of years to reach the surface (random walk
Hmm, please compare relative funding between current fusion research and the amount of funding poured into the Manhattan Project, as a fraction of GNP. I don't think that either fission bombs or fission power plants would have been created with funding like that which goes today for fusion research. MASSIVE government programs allowed that research to be carried out and carried to fruition. The flip side of that is that a huge investment in fusion research- like, say, the amount that the federal government is prepared to dump into increasing available fossil fuels- could very well bring commercial fusion reactors into the realm of viability. So - does politics have anything to do with why we don't have fusion yet? Since it lacks a wealthy industry group to bribe politicians to fund it, while the oil companies have exactly that wealthy industry group, I think it does.
"I've always been suspicious of these so called Big Science projects"
Oh yeah - stupid stuff like the Manhattan Project would never be necessary to create fission bombs or fission power plants, eh? And that manned space flight - just tell me how you're supposed to fly around the world when the world's flat?
Big Science very often isn't justified, but is most justified in those areas that require a massive upfront investment that would never be made by industry (fission and fusion are both good examples).
The economics wouldn't be because of more power generated, but because "extra" or "unused" power could be fed back into the system and sent somewhere else. A closed, self-sustaining system which is capable of routing power as appropriate, much like the power grid in the USA, but less centralized. You could use your reactor at home and sell power to your neighbors when you weren't there. Or your reactor could do a quick peer-to-peer auction (next killer JXTA app anyone?) in your neighborhood to find out if it would be less expensive to buy from a neighbor or to produce electricity itself.
So I was thinking more along the lines of clustering for sharing, profitibility and expense mitigation rather than clustering for total energy output increases.
.anacron
Actually, I believe Thomas Edison orginally evisioned power production in this way -- with a small generation plant on every city block. However, electrical utilities have figured out that producing power at really large power plants is more efficient than many smaller ones. A 50 kilowatt deisel turbine power station is more efficient at generating power than a Honda generator in everybody's backyard. And every tiny little gain in efficiency for the big utilities is money in the bank.
Yes, but I wonder if that all changes with fusion reactors. I am not as educated on the inner workings of them as I'd like. I understand the basic concept, but the energy requirements needed to sustain the magnetic field are probably the largest single energy expense in the reactor model. Once we achieve sustainable fusion the next step will likely be making the input energy requirements smaller (so the yeild is larger) and the first place I'd probably look is in the magnetic containment field.
What happens if the containment field fails -- the internal plasma would presumably fly apart, but would it dissapate or would it cause wide spread damage?
Does anyone have an equations or links or any online resources that would indicate what would happen if a "backyard sun" (i.e. home fusion generator) containment field failed? I'd also imagine if you had a "cluster" of these spread out over a home neighborhood or high-rise that a chain reaction could occur if the stability in one is lost. Much like current ICBMs work. A seed explosion which causes the rest of the reaction to start. I wonder what the safe operating distance between these things would be. Or how you'd even find out. Anyone have any ideas?
.anacron
How are you going to get electricity from the fusion reactor (heat)? No, we probably won't be using free electrons from the reaction (heat). The fusion reaction produces a lot more energy in other forms (heat). So (heat), you (heat) probably (heat) would (heat) use (heat) that (heat) energy (heat). Perhaps you would use heat (heat!).
/. have to be logical? Isn't dreaming and speculation allowed anymore?
Yes, heat is the current method of gathering kinetic energy for a power plant. But who's to say we won't find a better, more efficient means of energy capture in the future. Be able to use fusion to STORE energy much like chemical batteries do today. It's just a matter of time.
.anacron
Since when did the posts on
Because it's not yet possible I wonder if anyone has thought about this before -- would it be less expensive to "cluster" smaller fusion reactors together to achieve energy output, or is building one large reactor the "best" way? I just look at the progression of things: Room-sized computers->high-end workstations->desktops->distributed computing ... maybe power generation can follow a similar model? We've already scaled up -- moved from small output steam generators.. is it time to start scaling down again?
Steam is so primative. You'd think with a technical innovation as amazing as fusion, you should be able to find a way of stripping the electrons right off the atoms. Using steam is barely better than Og the caveman beating two rocks together to get fire.
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
Nuh uh to you, too. The system, in this case, is the Earth itself. Once the energy is here, all conversions just move the heat energy around different parts of the "system". And each conversion produces waste heat that gets leaked out into the system at large rather than going to where you want it to go. It doesn't go away until it is radiated out into space. That's just basic thermodynamics.
Also, if heat were "quite willing to radiate off the planet with minimal fuss", then we would have no "solar greenhouse" at all, much less any problems with it. The only difference between greenhouse heat from the Sun and energy sources on the Earth is just the source. Once you have heat, you have to get rid of it (at the right rate), whether it came from the Sun or not. :-)
Now, a more appropriate question is whether we could approach the scale of Earth-impacting solar energy with our own heat producing energy sources like fusion, fission and fossil fuels. I admit I have no idea of their relative magnitude.
Now, a more appropriate question is whether we could approach the scale of Earth-impacting solar energy with our own heat producing energy sources like fusion, fission and fossil fuels. I admit I have no idea of their relative magnitude.
I would have had no idea of their relative magnitude, either, except that I'm a Slashdot Reader.
The recent solar car race article included references that suggests solar energy flux is of the order of 1 kW/m2. With a radius around 6.3e6 meters, the cross sectional capture is around 1.2e14 m2, suggesting the solar input radiation is around 1.2e17 Watts. (Which also could suggest why CO2 emissions that affect solar gains and losses don't have to do much to cause an observable effect on the planet's temperature. But I digress.)
All the recent hubbub surrounding the California electrical generation capacity crunch has bandied about figures for big power plants that generate, oh, like 5 GigaWatts. Looks like there's a factor of about 1e8 before terrestrial generation gets anywhere close to Sol's warmth.
Given those magnitudes, I doubt man-made heat generation would be a problem. It is much more likely the problem would turn out to be some much more prosaic, like worrying about liquid Lithium being in short supply, or finding a way to deal with the irradiated equipment and byproducts of fusion reaction.
"Provided by the management for your protection."
You're just thinking about certain fusion processes. D-3He (deuterium/helium-3) is nearly aneutronic.
Also, power can be extracated from a hot plasma in several ways, not _just_ through the radiation flux. (eg, MHD.)
Good thing they're building this in California. I wonder how long it'll take to brown out one of these babies!
Mordred
That's true of the helium (both helium 3 and helium 4 are stable, while helium 2 and helium 5 have half-lives measured in very small fractions of a second) but not of the hydrogen. Tritium is beta-radioactive, with a half-life of about 11 years.
Worse is that tritium is not found in nature; it must be made in nuclear reactors. There have been incidents of tritium escaping into groundwater around plants made for that purpose.
Furthermore, you need energy to make the tritium, which raises your breakeven point.
A deuterium-deuterium reactor would be cleaner, requiring no tritium and having only neutrons as a radiological hazard; the waste would be helium 3, which lacks the superfluid properties of helium 4 but would still be useful for cryogenic cooling and lighter-than-air craft.
--
Ooh, moderator points! Five more idjits go to Minus One Hell!
Delenda est Windoze
Ooh, moderator points! Five more idjits go to Minus One Hell!
Delendae sunt RIAA, MPAA et Windoze
(1) The particles are very hot indeed. Their mass is low. The centrifugal potential well has to be very deep indeed to keep them from escaping. How well does this work? How hard is it to spin them fast enough? The electrons will escape the well more easily than protons/nucleii. How quickly will the plasma become positively charged? (Depends on the ratio of temperature to well depth.) What effect will it have on the operation of the machine that you have a huge current due to the very quickly spinning positively charged plasma?
(2) The particles are whizzing around, and are 'attached' to the magnetic field lines. This suggests that the magnetic field lines will get twisted very quickly, bringing the spin to a halt. This was my first thought, but if you make the field lines into loops (coathanger shapes) then you can whizz your coathangers around without twisting things up. Two problems with this: To make a magnetic field loop, you need a current. To make a very powerful one, you need a very large current. How is this done? Secondly, any 'stray' field lines that don't fully loop will get spun up very quickly, so even a very small non-looped field will magnify by being spun up until it causes you problems. (IIRC, galactic magnetic fields are thought to have been formed from very weak projenitors by this process.)
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
Its nice that the article failed to tell us if they even broke even in the amount of energy put in vs the amount of energy that they took out. I must say the idea looks very promising but I am dissapointed that they did not mention the energy input vs output so I could compare to past progress.
"You can now flame me, I am full of love,"
http://claw.bsdi.com/torek/elec/tesla.html
Sanity is a sandbox. I prefer the swings.
... in Canada:
http://www.iter.org
It's a massive international effort to produce a proof of concept, apparently the power output is going to be on the scale of a conventional power plant. They are expecting it to be finished in about 10 years (IIRC)
Such a price the gods exact for song: to become what we sing - Pythagoras
There's enough deuterium in the top inch of Lake Erie to power the entire planet for a year.
I'd say its damn near perpetual enough.
Also, the moon is rich in an isotope that is ideal for fusion power. I read several years ago that the Japanese kicked around the idea of the possibility of mining the moon for fusion fuel in the future. I'm feeling too lazy right now to look it up for you. But basically, fusion is potentially a source of nearly unlimited, clean, failure proof safe, energy. Its the Holy Grail of energy production. And we've been damn close to realizing it for decades. It's been demonstrated feasible, but now its the engineering problems of getting it economically feasible (ie produce more power than it takes in).
Derek
Sounds like a perpetual motion machine that creates extra energy.
You still have to add deuterium and tritium.
"In this house we OBEY THE LAWS OF THERMODYNAMICS!" -- Homer Simpson
--- Brent Rockwood, Development Lead
BRENT ROCKWOOD, EST'd 1975
Man, if we could just get that whizz-bang computer chip off 007, and do away with Dr. Evil. All the worlds problems would be solved.
As far as my high-school physics & chemistry education allows, it is true that Deuterium is found in large bodies of "light" water in the form of D20 or "heavy water" (certain tests are done using emissions from the Deuterium in "light" water or something like that).
The problem is that it exists in extremely small amounts (somewhere in the order of a particle of D20 per few million particles of H20). So to extract it would require an even greater investment in industrial resources than you would get out of fusing the few pounds of Deuterium that you'd extract. It's like saying that we could extract Gold from the oceans because it exists in trace amounts in sea water. Yes, that's true, but it requires so much effort that extracting it is not economically viable.
Self Bias Resistor
----------
When the pin is pulled, Mr. Grenade is no longer our friend.
The ITER project is very old....The version they are planning to build in Canada is a stripped down version of the original project. The US pulled out of the original ITER project partly becuase the US scientific community is divided on whether money spent on a reactor sized tokamak is a good idea or not. We've learned alot about the limitations of a tokamak design in the last 20 years or so. There is now strong interest in the US to look at other designs other than the standard tokamak doughnut. Low aspect ratio devices(think an apple shape rather than a doughnut) which solves some stability problems that plague tokamak operation. There is also alot of interest in bringing back the stellarator..which is a fully 3-D device (think doughnut, but a french crueller)..now that we have to computing power to start thinking about doing fully 3-D plasma physics. Numerical simulation of fusion temp plasma physics is...HARD....and we are just getting to the point of having enough affordable computers (beowolf) to start doing 3-d modelling of plasma systems.
Very true. I wish I had a moderator point for you.
Furthermore, the 'great american inventor' didn't invent hardly any of the inventions credited to him. He had a laboratory where he hired brilliant but introverted, couldn't sell ice cubes in hell, geeks to invent things, and let him promote and take credit for those ideas.
His primary contribution to America's economic machine was to invent a system of mass producing intellectual "property".
The best way to prevent this from happening is complete disclosure of all knowledge pertaining to fusion, and large-scale mirroring of that information all over the world.
Increasing the earths albedo and reducing its greenhouse effect help to a point. In fact the increasing occurance of cloud cover might begin to block out the sun completly, but that would be an extreme case.
Thermoeletric generators that absorb energy from temperature differentials then beams them into space as microwaves could be possible, or we could simply transmit generated energy into space for consumption off-planet.
A higher dependency on Solar Cells and heat-energy-converting/trapping devices could also help lower the amount of heat we have to deal with.
umm, these devices, which allow you to store heat energy only take heat out of the system until you actually use them, at which point they return all the heat they took originally.
Sure fusion may allow us to have access to alot more heat, but the stuff is quite willing to radiate off the planet with minimal fuss (Given proper atomospheric conditions).
Now turning our planet into a solar greenhouse or toxic waste dump- those are potential problems. "Heat Pollution" is a non-issue.
Seriously, at a fusion conference a few years back one of the speakers raised the "in ten years..." issue and said that by underestimating the difficulties of building a fusion power plant, the industry had lost its credibility. He started talking in terms of 50 year horizons. It was at that point I gave up hope for fusion.
Consider: for fusion to work, you've got to jam at least two protons together and corral at least two neutrons. Since free neutrons are unstable, you've got to generate them in situ. You can't corral them, they don't interact with magnets so you have to hope that two of them happen to be around just at the moment you've managed to squeeze some protons together. Only problem is, the neutrons, once generated, are fleeing the plasma as fast as their little quarks will carry em.
In an H-Bomb, you don't care - you wrap the reaction chamber with uranium and let the neutrons fission the u-238 and u-235. Yep, even u-238 fissions if you've got scads of neutrons. Our H-Bombs generate 70%+ of their power from the neutron - uranium reaction. Less than 30% comes from fusion itself. So unless you wrap fusion chambers with uranium - hmmmm , there goes the neighborhood - you're going to have a heck of a time getting any useful work out of the neutrons.
Bottom line - fusion is a never ending funding hole. Fund the research, but recognize it's a long shot that the research will pay off in our lifetime.
Not sure where that comes from. The GA announcement merely said they had managed to smooth the plasma by spinning it. Thought there was a lot of speculation about "improved prospects...", there weren't any claims of significant energy gains.
You can read the original release at their web site.
IRC Helium-3 isn't very common. Where you gonna get it from?
Secondly, how easily does D-3He fuse? It takes a MUCH higher temperature and pressure doesn't it? That takes energy, and energy you need to get back in order to break even (energy) or break even (money).
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"Right now, there are some severe issues with getting it to work at all.
But, let's assume that tomorrow there is a breakthrough and it all magically works perfectly.
The problem is that most of the energy of the fusion reaction comes out in the form of neutrinos, which you can't practically stop, some heat, but mostly fast neutrons.
The fast neutrons don't dump their energy into heat energy very easily at all. The best scheme I heard for doing that was lining the inside of the fusion reactor with lithium, transmute that for a bit and then stuff the lithium into a conventional fission reaction and use THAT to make steam.
And that's the most realistic scheme I am aware of. The fission reactors, and the disposal issues of all the elements that are getting irradiated make this very far from being a clean process. Fusion power is never going to be clean.
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"Is heat the major energy output?
produce energy significantly in excess of what they're putting in
And this isn't enough? Sounds like a perpetual motion machine that creates extra energy. Think about it. Put these in a "Distributive Model" and I don't think we need to worry about rising gas prices.
Maybe I'm just not *getting it* (and I can already feel the replies that are gonna call me an idiot...).
--
Good quote, too many chars. Seriously, the slashdot 120 char limit sucks!
(Slaps Forehead)
Your absolutely right. My bad.
In this setup plasma particles align themselves with the MAGNETIC field, which is threated through the magnetic rings (duh). The Electric field is generated in the center and radiated outward toward the edge of the bottle.
For more information on this containment theory please visit my professor's web page at: Centrifugally Confined Plasmas
You can also get a good scematic of the design at: This link
I apologize for the confusion.
The tokamak reactor design uses a torus (donut) shaped ring to confine the plasma. Another design is one my (former) physics professor and the group he is in are currently working on. Basicaly the design consists of two magnetic rings, one above one another. The electric field is threaded through the bottom one and through the top one. The electric field bulges out between the two rings making a sort of "coat hanger" cross section between the rings. This forms the shape of the magnetic bottle.
Classical EM shows that the plasma particles will be confined to the electric field lines and helix around them. If there were no magnetic fields the particles would "escape" this system through the top and bottom of the E-fields.
The neat part is that when the magnetic fields change, the system imparts an angular momentum onto the plasma particles. The result is that the plasma spins (in the same plane as the magetic rings). Since the electric fields are in a bent, the centripetal force will push the plasma into the middle of the "bottle" and away from the top and bottom. The anaolgy he gave was take a bead and put it on the bent wire of a coat hanger. Now spin the hanger around its long axis. The centripetal force will push the bead to the "bulge" of the hanger. Similarly, the plasma should be pushed to the "bulge" of the magnetic bottle. Hopefully when enough energy is added to the system the plasma will fuse.
Last I heard the group this professor works in was trying to get funding to program a model of the reactor, so no working model is on the way soon. He claims that thoeretically this setup should be able to cross the energy in-energy out threashhold. Of course only time (and money) will tell.
I think you mean 20 million less people on the planet. Sure, there was a boom AFTER the war, but no.. the war did not create 20 million new people.... if you don't believe me just go ask the jewish communities.
"This is where god would go if he wanted to get off blow!"
Actually, if the containment field failed, the fussion process would stop (it needs the pressure the field generates to fuse), and you'd only be getting no power out of the generator. You might need to replace the container, as well as whatever component failed to cause field collapse. As for the hydrogen-who cares? it's probably in a vacuum, and there wouldn't be enough of it to cause a problem. Remember, fusion produces many orders of magnitude of power more than burning the hydrogen would, so the container would be rated for the active fussion process.
Firethorn
I don't read AC A human right
You wouldn't want to use lead or concrete for this. I know that lead would melt at those temperatures, and I don't think that concrete would maintain integrity when it's that hot.
Firethorn
I don't read AC A human right
Yeah, but all power plants do this now, so it's a known concern. You take down a coal plant and put in a same rating fission/fusion plant using the heat cycle to produce power and you'll be producing the same heat as the coal plant. Difference is that you'll be substituting nuclear waste/irradiated containers for coal ash. Personally, I'd rather have the nuclear waste/containers. They're easy to handle and contain. Coal byproducts are produced by the kiloton, and are known hazards. It's a level of toxicity thing. The Coal byproducts aren't as dangerous, but are produced in orders of magnitude greater quantities.
Firethorn
I don't read AC A human right
Can someone explain to me what happens NEXT? Do they heat water to form steam to turn a turbine? Or is the process much more advanced than that now.
It'd be quite cool if they could just go BAM, plasma->electricity.
But what is the actual process (yeah, I'm at work, and far too lazy to go research this right now for myself)
Inputs to the fusion reaction are hydrogen isotopes (safe) the outputs are helium isotopes (safe). The only problem that might be expected would be heat, and we all know heat is dangerous.
Spring is here. Don't believe me, look outside!
There is no way it could "spill all over you," unless you're for some reason inside the reactor torus when the thing fails, in which case you might get a Darwin Award.
A$$hole physics answer
OK....it wouldn't even start due to the additional mass inside of the torus. This would not allow the plasma to heat up even close to the temps needed to create it.
Humorous answer
SanDiego, California (Reuters)
Freddy "Two-Parts Hydrogen, One-Part Oxygen" Johnston was the first person to experience life about 1 second after the Big Bang when he crawled inside the DIII-D fusion test reactor last Saruday night. Just before a test firing of the reactor (and just after Freddy consumed 15 Mai-Tai's and 3 shots of Tequila), the father of twelve was looking for a nice warm spot to sleep off the effects of his earlier testing of mood-altering beverages. Freddy not only snuck by the three guards outside, but also several dozen surveilience cameras to finally find a nice, warm spot inside of the fusion reactor. Unfortunately for Freddy, the reactor core wasn't inspected before the reactor was closed, pumped down to near vacumm and heated to about 40 million degrees Celcius. As Freddy's molecules brokedown into their atomic components, and then into a plasma, scientists running the test were a bit perplexed by their readings (1 part deuterium, 2 parts tequila, 1 part sloe gin) which cause them to go inside and find the (now vaporized) remains of Freddy. Freddy's last thoughts caputred by the security microphone were "Ooh...looks like a big Jelly donut!".
B
Flamebait
Serious inquiries only.
> make their scale-model fusion generator produce energy significantly in excess of what they're putting in
Umm....according to the article, fusion reactors haven't really produced large quantities of power. The linked article states, "The experimental tokamaks that exist around the world, such as the Joint European Torus (JET) reactor at Culham near Oxford, have to date not progressed far beyond the break-even point."
But, at least they're finally producing energy now. =-)
Plasma does not like to cross magnetic field lines; this principle is in fact how tokamak reactors work. If your reactor was continually generating new superheated plasma from the energy in the reaction, you could maybe split off a stream of it and send it down a different channel.
Let that stream of plasma impact some new magnetic fields. It will push on the field lines, imparting momentum to them. This could accelerate the magnets generating those lines, even if they were on the other side of the wall. If those magnets were attached to wheels, could you actually make a "magnetic turbine", directly converting the kinetic energy of the plasma into mechanical work?
Maybe a real physicist can enlighten me... Is this possible?
I stole this sig from someone cleverer than me.
If you could find a source of antimatter to mine, you'd be golden. But that doesn't seem likely.
I stole this sig from someone cleverer than me.
Um I'd be mighty scared if hydrogen had only one neuron;because namely, it would lend evidence to my jewish friend that the universe was a brain fart of god/jehovah. Well maybe the CBR is him lighting that fart, oh I should stop ;)
An Education is the Font of All Liberty
Well, solar cells work a bit differently, though I forget the specifics right now. Something about the light bumping electrons off of metal alloys (I could be getting mixed up with chlorophyl). Either way, if a material could be created that could convert heat directly into electricity (like a solar cell does with light) then the efficiency of any reactor would go up. Note that I am not saying that the heat -> electricity conversion would have to be 100% efficient so it shouldn't violate the laws of thermodynamics.
These things are supposed to pump out huge amounts of heat, right?
Couldn't that be considered an environmental problem?
Controlled thermonuclear fusion with a continuos isotropic neutron output was achieved by Philo Farnsworth in the ITT labs in 1967.
Currently Chrysler is selling a neutron source based on a simplistic recreation of one of Farnsworth's earlier tube designs. The device is advertised as creating neutrons by controlled thermonuclear fusion - which it does.
There are several amateurs who have duplicated Farnsworth's work and have achieved fusion in their basements.
These facts are a massive embarrassment to the people at the top of the magnetic fusion community - and as a result there is zero funding available for people using the electric field - inertial confinement principles outlined in the Farnsworth patents.
Most people in the fusion field have never even heard of Farnsworth.
Farnsworth is best known as the person who created the entire system of television in 1927. Farnsworth is enshrined in the Inventors hall of Fame at the patent office in Washington DC. Sadly Dr. Farnsworth suffered a series of strokes shortly after his fusion work and died in 1971. His work has languished in obscurity ever since.
Wasn't it 1.21 Jigawatts?
I donate all spillover Karma to the charity of my choice... Ada was still a babe despite what people may say...
This comment has been submitted already, 276473 hours , 30 minutes ago. No need to try again.
I think you were compiled with the lameness filter. What gives with this? Time to go back to the drawing board.
--
Entropy ain't just a good idea. It's the law.
Which do you think we'll run out of first?
Petrolum (A complex chemical formed from bioloical and geological funcitons, found only on Earth)
Enriched Uranium (a heavy element)
Deuterium (Hydrogen with another Neuron)
For both Uranum and Hydrogen's isotopes, we can always just go and look for them elsewhere. For Petrolium, well, unless we find a place that had life thousands of millions of year ago, we're not finding it anywhere but home.
that the only way we have invented to caputre the energy of a nuclear reaction was by superheating water and using steam pressure to turn turbines. That always seemed like a hack way to collect the energy. Anyone know if the energy collected from this thing is more direct than heat+water=turbine-power?
Well, your fingers weave quick minarets; Speak in secret alphabets;
std::disclaimer<std::legalese> sig=new std::disclaimer; sig->dump(); delete sig;
Highly unlikely. All the evidence I've seen (and gathered from talking to a friend of mine who's a transit planner) shows that cost alone plays relatively little role in determining individuals' choice between public transit and driving. What it primarily comes down to is convenience: People make their transportation choice based on what they perceive to be easier for them. If gas prices in the U.S. doubled (as they arguably should), you'd get a huge amount of griping, and maybe a handful of people would change their habits, but most people would just suck it up and continue driving -- because in most places, for most people, it's simply way too much of a pain in the ass to take mass transit. At least, it's perceived to be a pain in the ass, and perception is reality in this kind of thing.
Incidentally, mass transit is not, in general, particularly cheap to begin with. For example, the cost of operating the bus system in Seattle, where I live, works out to something like $5 per ride. (Of course it's subsidized so riders pay only a fraction of that amount.) There's a new light-rain line -- one line, not a network -- proposed for the city that looks like it will cost upwards of $4 billion (or about $8,000 per city resident) simply to construct. And of course, in this running-out-of-energy scenario we have to take into consideration that as energy prices climb, so to will the cost of operating mass transit too (buses and trains require pretty substantial amounts of power either in the form of fossil fuel or electricity).
Yet the really insidious problem isn't money, it's time: People don't want to wait for public transit to arrive, and they don't want to cope with the fact that it doesn't go door-to-door like a private automobile. For some strange psychological reason people are much more sensitive to waiting around two minutes for a bus to come than they are to, say, crawling slowly through traffic for half an hour.
I'm not anti-mass transit, I'm just a realist. It's hard for me to see energy scarcity and cost reducing dependence on the private automobile (at least in the U.S.) unless we're talking about an order-of-magnitude difference, and that's a long, long way off. (Proven oil reserves are larger than they were 30 years ago, and all that...)
"Biped! Good cranial development. Evidently considerable human ancestry."
In the meantime, why are we wasting time drilling for oil and chasing cold fusion pipe dreams when we should be pushing forward in the direction of the infinite improbability drive.
Paladium fuel is incredibly expensive and rare. But all you need for the IID is a bit of fairie cake and a cup of tea.
Wait- you're turning into a pengin. Stop it.
Inside the cavity a plasma of deuterium is heated to 100 million kelvin and held in place with powerful magnetic fields. Deuterium is a heavy isotope of hydrogen, and when its nuclei collide under this intense pressure, some of them fuse to form helium, releasing large amounts of energy.
The consortium on the global "Funny Talk" crisis will be starting up next year!
Don't read this!
The previous poster is talking in Kelvin degrees. Kelvin is the way of calculating temperatures in Termodynamics and about everything else.
The Kelvin zero is -273 Celsius IIRC (yes, minus 273 Celsius). This is what is called "absolute zero".
Celsius zero is +273 Kelvin. And, then, to get your Farenheit, you do Farenheit=32+(Celsius/5)*9 , so its roughly Farenheit = 32 + (Celsius/2).
Now, 26.7 Kelvin is roughly a 1/10 of 273 Kelvin.
Here's your 10-factor!.
Enjoy.
Well, we're still plugging along and maybe we'll have commercial and/or military fusion power by 2020, but so far it sounds like the problems with using it remain the same:
... my point is, we only think we know what goes on inside the sun, by inference, and our perceptions - no promises that other things we have no idea of couldn't happen, like nifty white holes or other cool side effects.
1. Eventually the shell becomes radioactive. Not as much as in fission reactors, but it does happen. We still do not have proper disposal procedures for nuclear reactor shells - technically, we should lift them up, barge them down a river, put them in a plastic bag (or some kind of skin), and sink them down to the induction zone of the continental plates.
2. Power distribution still suffers from the main problem - a lot of energy in one place. You lose a lot more energy when you pump it out onto the grid.
3. They still make great sites for international terrrorists to play with society - if a plant produces 10 percent of the grid and you cause it to fail at peak load, you can get some nifty cascade blackouts in the grid; the same goes for pushing it to higher generation. This is why it's good to have multiple grids and multiple power sources in multiple places.
4. For all we know, there are star guppies that like to hop and play around the sun, causing nifty splashes (solar flares) in their frolics. Some adventurous ones might see the shiny pebbles on earth and decide to go for a jump - oops, there goes life on earth
5. Heat. Using this creates heat, liberates it. Are you sure you want to make the planet warmer? More heat in system means I get beachfront property sooner than 2100. Nothing's free.
It all comes down to this - all power sources have unanticipated side effects and environmental costs, we always get suckered by the bright side and ignore the dark side of the equation until after we start using them on massive scales in long-term production.
--- Will in Seattle - What are you doing to fight the War?
An IID has already been developed. Unfortunately, during its first successful test it changed the laws of physics in such a way that the IID's existence was no longer possible.
fusion is what we're going at here. Fusion doesnt require (or generate) the nasty radioactivity that fission does.
-
of course, these kind of reactions are the 'ideal' energy source, assuming you can get the necessary fuels and equipment in place. Of course, that's still a long way away. We're closer on fusion in the sense of having a usable energy source.
-
iirc, i was reading an article the other day that said you can generate electricity directly from the spinning plasma. I (or the article) could be wrong however.
-
This patent was filed 3 years ago. Anyway it's good to know its progress.
If they get this right, we'd effectively have a safe, inexhaustable source of clean energy. You can only wonder what the world would be like:
- All roads with an inductive loop and electric cars standard
- Pentium IX 100 Ghz combination processor/home heating system
- No more turning the lights out after you
Reliable, Great Value Hosting: $7.95/mo 2.4G/120G
How are you going to get electricity from the fusion reactor (heat)? No, we probably won't be using free electrons from the reaction (heat). The fusion reaction produces a lot more energy in other forms (heat). So (heat), you (heat) probably (heat) would (heat) use (heat) that (heat) energy (heat). Perhaps you would use heat (heat!).
If we use heat, we probably would use some sort of fluid to capture the heat energy for conversion to kinetic energy, and from that on to electricity, just like a conventional power plant. So, no matter what characteristics the reactor has, it would be tied to the characteristics of fluid turbines of some sort. As it happens, generally the bigger the turbine, the more efficient it is.
I might also wonder how the extreme amount of equipment redundancy (lots of expensive equipment) could make clusters of reactors competitive. These aren't mere computer cases; each facility would have to have immense amounts of control equipment. All of that control equipment is redundant--one could work as well as 50, if there were only one reactor, instead of 50--but actually becomes *less* safe as the redundancy increases. That's because if any one of those control units fails, that system fails. If the control equipment is preventing a toxic leak of some sort, that failure could be disasterous.
During Mao's Cultural Revolution in China, someone sold the leader on the idea of each family having its own iron smelting furnace, as a means of modernizing China's manufacturing process. The result was a disaster. It is more efficient for a group of trained people and a dedicated location to manage large amounts of iron smelting than it is for millions (or billions) of people to do their regular work and smelt iron on the side. It is also less toxic.
Taking stuff apart since 1969 (TM)
Oh my, suburbia invaded by giant mutant dandelions, what a nightmare, or extremely low-maintenance lawn, depending on your approach to yard work. 8-) Except that these were found "in an area that was untouched since the days of the accident," leading me to suspect that these are just ordinary dandelions that got left along long enough to grow really big. I have no idea how big a dandelion can grow, do you? But you get enough people out looking for something weird and they are going to find something, because there's always something weird out there. Call it the Erin Brokovich effect.
I wouldn't have wanted to save that gas in a tank and breathe it all, but the way it was vented it would have spread over a wide area and raised the background radiation level a fraction of a percent. A coal-fired plant releases more radiation in the fly-ash. Your TV set and CRT computer monitor emit more radiation. It was nothing to worry about, except that the way this happened (a stuck valve undetected for hours) suggests that either the operators were incompetent or the control console was beyond human comprehension...
Fusion power might have less environmental impact than solar cell production, and it doesn't cut out around supper time. I'd certainly rather have a fusion plant nearby than a giant bank of lead-acid batteries, but I think there are better ways to store a city's worth of solar power for the night...
your analogy about gunpowder is 100% wrong.
, 00.html
see this article and read it: http://search.ebi.eb.com/ebi/article/0,6101,33623
A: None. The Universe spins the bulb, and the Zen master merely stays out of the way.
Yeah, but what if we say maybe current reactors produce only 1.02x as much energy as they put in, since you pulled that 1.1x out of your ass anyway. Then we get ((4.4-1)/(1.02-1)) or 170 times more energy! That sounds really good! But wait! What if we pull some different numbers out of our ass? 1.003 gives us 1033 times as much energy! This breakthrough is sounding better and better all the time!
main(c,r){for(r=32;r;) printf(++c>31?c=!r--,"\n":c<r?" ":~c&r?" `":" #");}
For black bodies, the radiation power is proportional to the fourth power of temperature. The radiation received per unit area is inversely proportional to the square of distance. Putting these together, if we assume the radiation earth receives from the sun is in equilibrium with its own radiation into the space, then
(T/t)^4 = 4 (R/r)^2
where T, t are the surface temperatures of sun and earth; R, r are the earth-sun distance and the radius of earth. The factor of 4 is the ratio between 4pi (in area of sphere) and pi (in cross section).
So this comes to
t = T / sqrt(2R/r) = 26.7 K,
given R=1.5e11 m, r=6.4e6 m, T = 5800 K.
This is far below 0 degC (off by a factor of 10). Why? Can this be explained away by the deviation from blackness alone?
Yeah, fusion seems to `get closer to reality' once every ten years or so, and they've been saying the same thing for the past 30 or 40 years:
"Must be funding time again!"
Most likely the #1 Unfunny Meta/Moderator on
It seems that through most of the Earth's history we had Ice Sheets that covered Canada and Russia and kept most of the now moderate climates cold. Recent studies seem to suggest that civilization grows when the climate get warm and the ice sheets retreat. If human beings can end all Ice Ages as long as we are here, would that be such a bad thing?
"Energy is far cheaper now, and continues to drop in price..." Funny, I seem to recall my energy bill going through the roof last month. Seriously though, I don't expect the energy companies to go running to fusion, unless its sigificantly cheaper than fossil fuels. Though I doubt that the consumer will see much of a price drop. Let's face it, they will just use the extra savings to pad thier profit margin. Ever notice how quickly prices go up, then creep back down real slow?
Necessity is the mother of invention.
Laziness is the father.
... Alright, now what can we do with it?
While I'm sure this question has been aimed at the more creative of you by your phb's, it has an insidious quality about it in this discussion. Namely that someone is getting close to creating a really efficient highly energetic system. Great, then what do we do with it?
While I'm sure this'll risk being labeled redundant, I noticed that several posts raise the question of getting energy out of this system.
The answer, at least since Cestesibus's chronicler Hero recorded it, has been to let the system transfer energy into an expanding liquid, and use that liquid (air, steam, etc) to drive a mechanical system.
An interesting paper (warning, pdf) supporting an alternative fusion concept describes obliquely how magnetohydrodynamics may provide an inductive transfer of current from the plasma mass to the surrounding apparatus with an efficiency ranging from 70 to 95% depending on the fuel used to form the plasma mass.
Nietzsche on Diku:
sn; at god ba g
:Backstab >KILLS< god.
Remember the villain in "Batman 2"? He was proposing a power plant that drained power from Gotham City. It looks like the technology is catching up with Batman at last. What next, utility belts?
Don't blame Durga. I voted for Centauri.
It is a problem with deuterium-detuerium reactions, though, but no worries, there are oceans of helium-3 in Jupiter... we just gotta extract it.
Also, fusion will be MUCH cheaper than gasoline. Consider the fact that the fuel supply for fossil fuels is limited, wheras deuterium is found EVERYWHERE. We have oceans of it here... It is a very good long term solution for any technological civilization, just in terms of fuel supply. Burning old dinosaur bones will only last so long.
Of course we have had the technology to make technically* workable fusion power plants for quite some time. You just build a geothermal-style power plant in someone else's back yard. You then drop a Hydrogen Bomb... er... I mean "fusion powered heat generating device" down a deep shaft and set it off. The heat released is recovered in a method similar to the way geothermal power plants work. Two H-bomb sites... er... I mean "heat recovery areas" would be needed for continous electricity generation so that one would be functioning while the other was being prepared for the next detonation... er... I mean "heat release event". I can't find the source of this design, but I know it has been around for a while.
* I doubt it would be economically workable; and that is the important measure of a power plant. It certainly isn't politically workable; it would undermine non-proliferation efforts by introdicing the idea of non-military H-bombs.
Did you know that a fusion reaction releases far less energy than what is being explored at Fermilab, CERN, and (soon to be) SSC? Basically, by accelerating protons and anti-protons in opposite directions (not difficult to do, since they would naturally accelerate in opposite directions in a magnetic field) and smashing them together, you fully put Einstein's E=mc^2 equation to use. All mass goes into a whole crapload of energy. Harnessing that energy? Still working on that. Creating the anti-protons? Very time consuming. But, all in all, very doable in the not-so-near future. Compare that to a fusion reaction. Sure, E=mc^2 still works, but it's not really what it seems to be... You see, the m is actually change in m! And in fusion, you change about 1% of mass into pure energy. Fission, by the way is worse, at about 0.1% efficient. And don't bother about fossil fuels. They're about 1 millionth of a percent. If you want to know more... I suggest you check out "The God Particle" by Leon Lederman (Nobel Prize winner in physics and former director of Fermilab). peace out.
IWARS.
People, in general, disappoint me. Politicians even more so.
No, the fairie cake is if you want to build a Total Perspective Vortex!
You are Here -------->.
Fascism starts when the efficiency of the government becomes more important than the rights of the people.
I imagine the plasma ball would very quickly expand and cool as soon as it broke out of containment. The hydrogen/helium would go up, not down, and just float around in the upper atmosphere, which is what H/He does. It would ruin the day of anyone standing close by, but it wouldn't eat the planet or anything.
Or perhaps not. IANAP.
Just remember the Manhattan Project was military war project to design a weapon of mass destruction. This tends to get priority over any domestic research. As to safety concerns, every new invention has a hidden drawback and sometimes has lethal consquence. Poor Madam Currie.
I believe what you said is part of the theory of cold fusion, but it doesn't apply fission or to the type of fusion we are talking about here. Proof: go to site http://ippex.pppl.gov/ABOUT_FUSION/FUSION_DOC2.HTM L it explains how fusion works.
Another question is: What if we were not burning fossil fuel? How long can plant life last with .3% of CO2? Maybe (I know this goes far, and i'm not in anyway shure about this) it is good that we return CO2 to the atmosphere. Plants use up more CO2 than animals (except human beings...) burn. How long would this have continued? Isn't the self repairing program mother earth has running responsible for some catastrophic vulcanic eruptions millions of years ago? Maybe we are saving the world by burning fuel!! Just imaging, what a joke. Still I vote FOR Kyoto.
For the last few decades, we've heard that fusion was going to be a real power source in "about ten years." If we are actually getting lots more out than we put in, getting there cheaply is all that remains. MAYBE, we are only ten years away now. Personally, I'm waiting 'till someone says five.
I'm not quite as pessimistic. They have reached the point where they are getting significantly more energy out than they are putting in. The seems to be a legitimate chance that the process is close to correct and merely needs more tech and more efficient processes. I don't have the physics background you appear to though, so I won't be too strong in my statements.
It just bothers me how tough it is to make a really good form of efficient environmentally friendly energy. Fusion is better than fission, which is better than gas, which is better than coal, which is better than...but really how good can it be?
I guess what I'm trying to say is that I remember talking to my high school physics teacher about solar power, and saying "why don't we just pave over new mexico with solar cells." Seems like a good idea, except for the new mexicans, but it isn't. Doing that would create a big gap of heat over the desert since it can't be radiated back, which would tear apart the climate there. So even solar power seems to be a bad source of energy.
Sometimes I just wonder whether we will be able to find something really perfect as an energy source...or even if we are supposed to.
Well AC if you said EMF fields ... I don't need to say anything else.
this is a good point, and to further illustrate the power of politics in these matters, I saw the monetary figure "$60 billion" used twice this week. One was the figure trumpeted for building a good, old-fashioned icbm shield, and the other was the estimated cost of building a Supersonic Mag-lev tube (with current technology) to, get this, England. Could we accelerate fusion research with $60 billion? IMO (hee-hee), probably.