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A Step Closer To Cheap Nuclear Fusion
ewsnow writes "The Focus Fusion Society reports that the scientists and engineers at Lawrenceville Plasma Physics have finally built an operational Dense Plasma Focus device. While still at less than half power, they were able to achieve a pinch on their device. The small company that Eric Lerner started recently gathered enough funding to start a two-year study on the validity of his theory regarding fusion-inducing plasmoids. If the theory holds, the device will produce more electricity than it consumes. In contrast to the billions of dollars spent on Tokamak fusion (think ITER), LPP is conducting their research on a budget around a million dollars. Yet, if it works, it will provide nuclear fusion with much simpler equipment and much less cost. Eric Lerner and Focus Fusion have been discussed on Slashdot before."
Sorry but the reaction "H + B -> 3 He" is nuclear fission -- the fission of boron.
You should take a look at the video they made on google; yes they are crackpots unfortunately...
Sigs are too short to say anything truly profound so read the above post instead.
Apparently, he's against cheap power AND cheap food. The poor should starve! That'll solve the problem.
Can you be Even More Awesome?!
Which is really not all that checkered considering building hydroelectric dams have killed more people than Chernobyl did.
http://twitter.com/OLDTELEGRAM
Your point of view is common, but not correct. From dictionary.com:
Theory: "a coherent group of general propositions used as principles of explanation for a class of phenomena: Einstein's theory of relativity."
A theory is a group of explanations for something, NOT a hypothesis that has been confirmed. Theories are generally formulated, then hypotheses (otherwise known as "predictions") are generated from them, then these hypotheses are tested. If a hypothesis that is supported by the theory is shown not to be true then the theory needs to be revised or discarded.
To use the example in the definition, Einstein's theory of relativity was always a theory. It became an accepted theory through repeated testing of it's predictions, including the hypothesis that light should be bent by a gravitational field.
This guy's idea sounds like it's technically a hypothesis - a prediction made by a theory, or by his interpretation of a theory (such as plasma dynamics).
... now we admit it's a dupe *in* the summary!
Folks, can we pretty please think of another name for this stuff? 50 years worth of misinformation is, I fear, holding us back. People here the word "nuclear" and immediately start shitting their pants with fear.
Folks, can you all stop reacting to stories regarding nuclear power on slashdot by falling over at your computers, foaming at the mouth, and shrieking about how the general public are all so stupid that they oppose any use of nuclear power because they're luddites and they're not as scientifically informed as all of us blah blah blah.
There are 104 nuclear reactors in this country. They provide almost 20% of the country's electricity consumption. They are not thronged by those hordes of sign-waving hippies that most of you seem to think are keeping nuclear power down. There have not been any new nuclear plants built in this country in a long time not because of protesters, but because they are insanely and hideously expensive to build. They are for the most part not cost-effective.
There are groups who argue against nuclear power for a variety of reasons, some environmental, some political, and some were formed to protest the operation of specific plants that have a track record of environmental damage. Some of these organizations are led by or advised by nuclear physicists and engineers, who know a hell of a lot more about the technical aspects of nuclear power than 99% of the people reading this.
http://en.wikipedia.org/wiki/Chernobyl_disaster_effects#Long-term_health_effects
Which, just as with Inertial Confinemenet Fusion, means they just traded confinement time for Temperature and density.
There's this neat little thing called the triple product which relates to the power output of a fusion plasma.
n*T*tau
n is the number density, T is the temperature and tau is the confinement time. In Tokamaks n is low and T and tau are high. In other fusion schemes tau may be low, meaning they need higher n and T to make up for it. Thus while this particular machine may not need to increase the confinement time, they will then simply have to increase either temperature or number density instead.
An important facet of LPP's research is that they are pursuing aneutronic fusion. This is truly clean nuclear energy. Explained well here. and here. Nuclear Power without Nuclear Waste: It's Closer Than You Think
Nuclear fusion has the potential to generate power without the radioactive waste of nuclear fission, but that depends on which atoms you decide to fuse. Conventional fusion approaches work with deuterium and tritium, while focus fusion works with hydrogen and boron. When a boron-11 atom fuses with a hydrogen atom the result is three helium atoms and energy, but no radioactive waste. This is because: the fuel (boron and hydrogen) is not radioactive, the reaction product (helium) is not radioactive, and the reaction releases no neutrons (it's "aneutronic").
Of course, nobody was actually watching for signs of problems in the banking system.
Err, apart from those government departments whose job it is to watch for signs of problems in the banking system - the SEC, Fed and FDIC? The fact that they failed spectacularly at noticing what was happening doesn't mean it wasn't someone's job to watch...
Man who leaps off cliff jumps to conclusion.
If I remember correctly from seeing watching the tech talk on youtube about a year or so ago, the idea is not to produce a continuous, stable fusion reaction, but to produce an unstable reaction that lasts for only a moment. By creating reactions many times per second, substantial amounts of energy are produced. (Hopefully more than is needed to initiate the reactions in the first place.) The device is in some ways similar to a spark plug.
Let's I am going to cut your break lines in your car, and rig the throttle so that it goes to full and stays there. i will then call it a test to see and call what happens an accident.
Chernobyl had it's safety systems bypassed, and then had the reactor put into a dangerous configuration which ran out of control since the safety systems were bypassed. Fact is very few nuclear reactors use the type of reactor that this can be done with. Also Chernobyl was 4 reactors and at least until recently the 3 that were undamaged were still outputting power for the region. Not to mention that American reactors, have a secondary containment shell around them something the chernobyl reactors lacked.
To avoid t happening again all one has to do is use an american or chinese reactor that is designed to turn the reaction off as it fails, instead of requiring a second stage to actually force the reaction to stop.
yes there is more than one kind of nuclear reactor. Some are safer than others. Some are designed so that they only produce power under certain situations and turn themselves off when those aren't present.
i thought once I was found, but it was only a dream.
You're miseducated about nuclear to the point of hilarity.
Some point on your comments:
- "Lots of waste" - Jimmy Carter's ban on reprocessing means that we produce lots of waste. If we allowed reprocessing, we could take the stuff out of the ground, burn it to the point where there is no energy left in it, and put it back within 50 years.
- "Containment issues" - Huh? If you reduce the amount of waste through reprocessing (see above) and glassify the rest, there is no issue.
- "50-100 years of uranium" - completely wrong. We have 100 years worth at current economic recovery levels. Because the fuel is such a minor part of the total cost equation of a plant, we can sustain a 1000x increase in the cost of uranium and it'll still mean we should use the fuel. Combine thorium breeder reactors, and we have something like 10,000 years of energy assuming 5% demand growth per year.
- "have to mine a mountain" - The coal the US burns for power has more available energy in the uranium & thorium deposits within the coal than can be obtained by burning the coal. It doesn't take mountains to mine for coal.
Seriously, do some reading that didn't come from Greenpeace.
"the only problems with nuclear power involved two incidents with 30 and 40 year old reactor designs where even then didn't come close to the kill score that coal has"
Unfortunately, while Chernobyl didn't entail an immediate large body count, the countryside is pretty well ****'ed for quite some time to come.
And, of course, the total body count isn't in yet, since there are still idiots who hang around there.
Well, Coal hasn't yet destroyed a whole city ...
Yes, it has. Let's not forget the countless people that received suffered from black lung or have died in collapsing mine tunnels, asphyxiation from odorless toxic gasses, among other things...
It's safe because the risk of using nuclear technology is a lot lower than the alternative of building a bunch of new coal plants that spew carcinogens, green house gases and far more radioactive material into the air than any nuclear reactor accident ever has.
Sigs are too short to say anything truly profound so read the above post instead.
So, they're avoiding the problem of confining the plasma, which clearly is impossible with a 1G K plasma without it being inside a supergiant star. However, Todd Rider's excellent, albeit depressing, papers on this topic seem open and shut on the prospects of generating net power out of a non-equilibrium reactor. Particularly with the p-B reaction, you lose all the net power to brehmstrahllung.
Lerner has done good PR, and I suspect he means well, but he's wasting his time. There isn't a magic reactor, dense or otherwise focused that will evade the physics.
Links to the Rider's papers on this topic at following link.
http://www.fusor.net/board/view.php?bn=fusor_future&key=1181660470
Another interesting thing about 'aneutronic' fusion is that you can do direct power conversion.
As the previous poster said, D-T fusion releases much of its energy in the form of fast neutrons. In order to convert this energy into electricity, you have to get the fast neutrons to heat up a fluid and then run a turbine or run some other thermal process.
If your energy is largely in fast He nuclei, these are charged, and you can convert the energy directly into electricity in several ways, like just running these charged nuclei up against a high voltage. (There are other better schemes).
That means you can get power with no expensive steam generation cycle--though since you probably need to cool the reactor anyway you may as well extract some power from the coolant as well. However, the whole cycle can be more efficient.
--PeterM
This again. Todd Rider's paper is essentially a straw man; his criticisms to do not apply to the Polywell, and they may not apply to the DPF either. His assumptions are flawed, and the resulting claims are too general.
I can't find the specific post I was looking for, but here is a comment from Dr. Nebel, the lead researcher of the Polywell. Dr. Nebel has also co-authored research on the periodically oscillating plasma sphere (POPS), which provides direct experimental evidence for something which should be impossible given Rider's claims.
I'm surprised that the DPF work has elicited nothing more than fusion humor from slashdot. While it is facing some significant engineering challenges, it is one of the approaches which should be taken seriously. (Along with the Polywell, General Fusion's approach, and the FRC based approaches from Helion and Tri-Alpha.)
While tokamak based fusion may still be 50 years away, will never burn p+B11, and may never be economically viable, there are other promising alternatives. We may very well have working fusion reactors in a few years, some even based on the elusive p+B11 reaction.
Actually, Three Mile happened because a PORV (Power Operated Relief Valve) on the pressurizer was stuck open. They were unaware of it (though things pointed to it, it had no positive indication of position), and as a result, secured cooling flow to the core, and the RCS inventory was lost through the PORV, uncovering the fuel.
That is an urban myth.
No it's not.
there's a few parts per million of uranium and thorium in coal, when you're burning billions of tons of the stuff that adds up fast, some of that material escapes into the atmosphere while the vast majority ends up in vast mountains of fly ash where it can freely leech into the ground water.
Check your facts.
Where the heck should the "radiactive" contamination of coal should come from? Sure, some coal mines might have such a contamination, but all coal? How that?
This seems to shock some greens because they have no understanding of what "background radiation" actually means but there's a certain amount of radioactive material in just about everything. it's not a matter of contamination.
you omit the fact that mining uranium and processing it and transporting it mainly is still done with fossil fuels
And you obviously have never bothered to pick up and pen and do the math because this is trivial.
So in the near future building more nuclear plants will increase the CO2 exhaust in a similar way as a new coal plant would.
Until the coal plant has been running for a day or so it might but you really have no grasp of basic math do you.