Could This Lump Power the Planet?

macdoc said:
Post 1905 for a certainty ;)

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To answer the OP - laserfusion is very much real. Energy has already been released....it's just not self sustaining.

I don't know if you completed the article but I have no idea what would lead you to think that engineering and science on this scale

http://www.newsweek.com/id/222792/page/2

would

a) not have an immensely strong theoretical base
b) lead up experiments demonstrating proof of concept.

It has both....that said - there may be other barriers unanticipated....that's why the money is being spent on a potentially commercial scale unit.

There is another being built in Europe approaching it from the traditional standpoint of magnetic confinement

http://www.iter.org/default.aspx?id=2152

http://news.bbc.co.uk/2/hi/science/nature/7972865.stm

This is big time science and engineering but in the backdrop of a seemingly forever receding horizon :(

Still the idea is commercial energy by 2030
http://nextbigfuture.com/2008/12/proposed-laser-ignition-fusionfission.html

One can hope _ do like this laser ignition fusion/fission hybrid as it may have a shorter timeline.
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Oooh thanks, this is just what I was looking for.
 
skeptigirl said:
Don't misunderstand me, that wasn't my point.

I am asking sincerely if fusion has passed from the takes-more-energy-to-produce-than-you-get or whatever the barriers were into the reaching-feasibility phase? This is not my area of expertise and this is the first time I've seen news it might be on the horizon since the cold fusion claims from decades ago.
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My impressions (from a ways outside):

ICF is pretty certain that they have solved all of the questions about how to achieve break-even. They just haven't built the device that implements all of those solutions.

MCF is building the device (ITER) that implements most of what they know about achieving break-even, but it's less clear that we understand enough to predict that it will work.

I would not be terribly surprised if ITER's main result is "we discovered a new plasma instability which makes break-even a bit more challenging than expected." I would be more surprised to hear something like this from the ICF community.
 
skeptigirl said:
Newsweek: Scientists at Lawrence Livermore National Lab are betting $3.5 billion in taxpayer money on a tiny pellet that could produce an endless supply of safe,
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Let me clarify something about the language used here. The tiny pellet in question is a deuterium-tritium capsule, the fuel for the fusion reactor. The phrasing of that title could be read to mean that one pellet could provide endless energy, but that's not the case. What's really meant is that we can make an (almost) endless supply of such pellets (deuterium and tritium can be extracted from ocean water), each of which would actually burn up quite quickly in such a reactor.
 
You don't get tritium from the ocean, you get it by putting deuterium or lithium into a neutron source (either a fission or fusion reactor). That's one of the reasons that fusion people always talk about putting a lithium-rich blanket around their reaction area---the neutrons from the fusion reaction "breed" their own tritium fuel.

Deuterium you get from water. This is isotope separation, but compared to U235-U238 it's easy and inexpensive, mostly because the H-D mass difference is so large.
 
Tubbythin said:
Don't they extract it from fission reactors?
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I was a little off in my previous statements. The typical production method is to use heavy water reactors (ie, deuterium). The deuterium, which is extracted from ordinary water, captures neutrons and converts into tritium. Plenty of deuterium in the ocean, so plenty of tritium available upon demand.
 
Ziggurat said:
I was a little off in my previous statements. The typical production method is to use heavy water reactors (ie, deuterium). The deuterium, which is extracted from ordinary water, captures neutrons and converts into tritium. Plenty of deuterium in the ocean, so plenty of tritium available upon demand.
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Agreed. Its something of a menace to the fission folk I think. So its really a win-win situation if they can do something useful with it.
 
But next year Moses and his scientists will fire it up with a full load of deuterium-tritium fuel, and Moses feels confident it will achieve "ignition," meaning a controlled burn in which you get out more energy than you put in.
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Can someone explain to me why/how this would not break the laws of thermodynamics?
 
dogjones said:
Can someone explain to me why/how this would not break the laws of thermodynamics?
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The same way burning coal doesn't break the laws of thermodynamics.

But more specifically to this case. Tritium and deuterium fuse giving helium-4 and a neutron. Helium 4 plus a neutron has less mass than tritium plus deuterium combined. That mass difference is then released as energy (good old E=mc2).
 
dogjones said:
Can someone explain to me why/how this would not break the laws of thermodynamics?
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They're not counting the potential energy of the fuel itself. If the "spark" takes more energy to strike than the "fire" produces, you can never extract energy from the process.
 
MRC_Hans said:
Of course it is wrong. We know what to do, we almost know how to do it, we're just not able to build the machine to do it yet. However, the obstackles are in the areas of high power lasers, supermagnets, high-power physics, high-power computers. What has happened in the last 40 years in those areas? What can be expected to happen in the next?

Hans
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This joke comes from the details of what has happened in the history of plasma physics.

The fundamental issue is containing the plasma. My plasma professor showed us a bunch of the neat ways over the years how we've tried to contain it, and then how unforseen details of the physics meant the plasma would escape.

He finished the discussion by saying, "The bottom line is, whatever you do, the plasma will find a way to escape. That has been our experience thus far. Maybe we'll solve the problem, but it's a hard one."

So what's going on with attempts at making fusion plants is that we put in more energy to contain the plasma than we get back out.
 
Tubbythin said:
The same way burning coal doesn't break the laws of thermodynamics.

But more specifically to this case. Tritium and deuterium fuse giving helium-4 and a neutron. Helium 4 plus a neutron has less mass than tritium plus deuterium combined. That mass difference is then released as energy (good old E=mc2).
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Ziggurat said:
They're not counting the potential energy of the fuel itself. If the "spark" takes more energy to strike than the "fire" produces, you can never extract energy from the process.
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Gotchya. Thanks.
 
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ben m said:
My impressions (from a ways outside):

ICF is pretty certain that they have solved all of the questions about how to achieve break-even. They just haven't built the device that implements all of those solutions.

MCF is building the device (ITER) that implements most of what they know about achieving break-even, but it's less clear that we understand enough to predict that it will work.
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Not quite. MCF is ahead because it has already achieved break-even. ITER is not about that, it is addressing the advances in science and engineering required to get from an experimental reactor to a commercial power plant. The problems ITER faces are not so much on the fusion side, since we already know we can do it, but are related to cycling fast enough to produce a sensible amount of power, removing waste, and things like that.

ICF, on the other hand, is pretty much as you say. It's achieved fusion before, but has never reached break-even. ICF has the advantage that it should be much easier to make into commercial power, since the problems noted above for ITER are generally easier in engineering terms than for MCF. However, it has the problem that it hasn't actually been shown to be physically possible to reach break-even yet.

I would not be terribly surprised if ITER's main result is "we discovered a new plasma instability which makes break-even a bit more challenging than expected."
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They shouldn't have problems reaching break even. However, it's certainly possible that we may hear something along the lines of "we discovered a new plasma instability which makes keep the vessel intact a bit more challenging than expected". Given that the requirements are already at, or in some cases apparently just beyond, the cutting edge, that would be quite a big problem.
 
I got confused because I did not understand the abbreviations used. However Wikipedia came to the rescue with good information.

MCF magnetic confinement fusionWP
ICF Inertial confinement fusionWP
Magnetized target fusionWP
 
BenBurch said:
EVEN if ITER is a stunning success, and its follow-on production plants operate reliably. we can build Thorium Energy Amplifiers at 10% the cost per MW generated.

And we could have the first one online in ten years, and build them quickly.

And we have a LOT of Thorium on the planet.

And I cannot for the life of me understand why we do not have a pilot plant being designed right now.
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If by "we" you mean the US, then as I understand it it's because given the amount of uranium we have, the amount of thorium we have, and the infrastructure already in place, it'll be fifty years before it's economical.

India, on the other hand, has little uranium but one third of the world's thorium, and is developing thorium technology right now.

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This overlooks the possibility of using a thorium system as an incinerator for nuclear waste ... I'm not sure whether it would justify the cost of building one, but it's worth thinking about.
 
Horizon programme-"Can We Make a Star on Earth?" Have a search on Youtube. I am in work at the moment so can't give you a link. Stick "Professor Brian Cox " in your search if nothing comes up. Even if it doesn't work it doesn't mean it is woo.:)
 
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