*BOOM* Over-unity controlled nuclear fusion!

I don't want to rain on the parade but they achieved what's called 'instantaneous unity'. What this means, is that during one or two laser shots, the power expressed exceeded the power inserted by the focused laser beams. This is a good thing. But not the end of the story.
 
docmirror said:
I don't want to rain on the parade but they achieved what's called 'instantaneous unity'. What this means, is that during one or two laser shots, the power expressed exceeded the power inserted by the focused laser beams. This is a good thing. But not the end of the story.
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Necessary, but not sufficient.
 
It is break-even fusion no matter how you slice it. But yeah, they have a way to go. But if they can get there say goodbye to energy shortages.
 
The other day I caught the tail end of a report on NPR regarding fusion energy. A program at MIT recently lost and then regained it's budget and US funding was provided to a similar, but much larger international research program. The expert interviewed mentioned that energy from fusion would not commercially be available until 30 to 50 years from now...
 
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Herman vanOoijen said:
The expert interviewed mentioned that energy from fusion would not commercially be available until 30 to 50 years from now...
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Fusion energy has always been 30-50 years off and suspect it always will be. It's theoretical, not practical. With climate change and energy independence key buzz words, all these scientists have to do is make a little "pop" in the lab every now and then and the funding will keep coming. Pretty sweet gig considering there are few people alive on the planet that can actually verify the "pop" they made really is what they say it is. Billions of people across the planet, including those that hold the purse strings have to take their word for it.

Moller will have his Skycar FAA certified and in Chevy dealerships before we have fusion energy. :rolleyes2:
 
Herman vanOoijen said:
The other day I caught the tail end of a report on NPR regarding fusion energy. A program at MIT recently lost and then regained it's budget and US funding was provided to a similar, but much larger international research program. The expert interviewed mentioned that energy from fusion would not commercially be available until 30 to 50 years from now...
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Predicting the timing of scientific development and discovery is a pretty tough challenge.

One breakthrough tomorrow and real fusion power might be viable in 10 years.

Alternately, physics and material properties may get in the way and fusion power may always be a dream.

The reality is probably somewhere between, but predicting the "when" requires quite a crystal ball.
 
Dav8or said:
Fusion energy has always been 30-50 years off and suspect it always will be. It's theoretical, not practical.
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For now. We've been able to make uncontrolled nuclear fusion a reality for over half a century. Perhaps it will never come to pass, but that's the pessimists view. Break even fusion was the holy grail of physics research not that long ago. They just reached it.
 
steingar said:
It is break-even fusion no matter how you slice it. But yeah, they have a way to go. But if they can get there say goodbye to energy shortages.
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No it isn't. Only if you forget how much energy went into their laser.

It's amazing how little progress has been made in ICF since I was in the field 30 years ago. We tried to get around the laser inefficiencies by using heavy ion beams instead. Except those suffer the same emittance growth problems the fuel does….well, reduced by a factor of 80 or so because the ions are heavy, but it's still the same problem.

Dav8or is right. It's always 40 years off. It certainly was 30 years ago. Should be 10 now…. But he's wrong about verifiability. That's part of it. And the funding for NIF comes from the strategic nuclear stockpile, so it WILL be there in the absence of nuclear tests, regardless of the scientific justification.

Uncontrolled fusion is a whole lot easier. You can cheat with a fission bomb. That you blow up and irradiate everything around you is kinda the point. That doesn't work so well for a power plant.

Fusion is the energy of the future, and always will be.

And it ain't nearly so clean now that everyone is talking about D-T fusion. That blows neutrons everywhere and makes a helluva lot of nuclear waste. Back in the day, we dreamed about D-D, which was a whole lot cleaner.
 
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I worked on the Tokamak project at Gen Atomics back in the 80s. I wasn't involved in the D-T parts, just the control and power electronics for supplying the reactor. It was always '20 years from success'. Gulf sold Gen Atomics, and then the internal project was shelved indef. I think they are involved in ITER now. Not much progress since the '80s, but I'm always hoping. Last I heard, Gen Atomics was making parts of the Predator drones.
 
docmirror said:
I worked on the Tokamak project at Gen Atomics back in the 80s. I wasn't involved in the D-T parts, just the control and power electronics for supplying the reactor. It was always '20 years from success'. Gulf sold Gen Atomics, and then the internal project was shelved indef. I think they are involved in ITER now. Not much progress since the '80s, but I'm always hoping. Last I heard, Gen Atomics was making parts of the Predator drones.
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The Tokamak was only 20 years off? With all the plasma instabilities those guys discovered? That was more than 20 years ago….

We never claimed less than 40, and the prototype power plant was always specified at 1 TW.

Henning, "harnessing" energy is not hard at all -- there are a lot of ways to use heat to generate electricity. Containing it might be a problem for some of the designs, but even the micro bombs are possible. The big barrier is not the heat exchangers. It's overcoming space charge density and getting the $%$^ thing to fuse without putting in more energy than it produces.
 
MAKG1 said:
The Tokamak was only 20 years off? With all the plasma instabilities those guys discovered? That was more than 20 years ago….

We never claimed less than 40, and the prototype power plant was always specified at 1 TW.
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Easy there sparky. Don't get your panties in a lot of knots. It wasn't a literal quote, just stuff that was tossed around back then. I can count backwards as well, and the statement should have been more accurately written as "back in the early 80s, they were always talking about it being 'only 20 years off'". I tried to summarize it with the "was" but I hope you switch to decaf one of these days, cuz you are far too critical about offhand stuff.

Now, when I start talking about effective yields, and toroidal field stuff, you can get back in my face.
 
MAKG1 said:
The Tokamak was only 20 years off? With all the plasma instabilities those guys discovered? That was more than 20 years ago….

We never claimed less than 40, and the prototype power plant was always specified at 1 TW.

Henning, "harnessing" energy is not hard at all -- there are a lot of ways to use heat to generate electricity. Containing it might be a problem for some of the designs, but even the micro bombs are possible. The big barrier is not the heat exchangers. It's overcoming space charge density and getting the $%$^ thing to fuse without putting in more energy than it produces.
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Well, isn't that where harnessing inefficiencies come into play?:dunno: Don't get me wrong, I have no objection to fusion programs, I think they are a good and necessary expense, like you, I think they are still a ways off from having a self sustaining over parity system.

As an aside, what do you think would be the result if we combined an accelerator/collider with the laser array focusing the laser at the point of collision? Can you feed a continuous stream into a collider?
 
MAKG1 said:
Henning, "harnessing" energy is not hard at all -- there are a lot of ways to use heat to generate electricity.
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Is most fusion energy gamma or neutrons or what? I thought that even capturing gamma was a challenge, considering how well it penetrates into anything.
 
Henning said:
Can you feed a continuous stream into a collider?
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I think LL Berkeley had Advanced Light Facility that worked on that principle, but I am not sure. I know that stream in their collider decreased over time (like minutes), but IIRC they re-fed it without stopping the whole thing, albeit in bursts.
 
zaitcev said:
I think LL Berkeley had Advanced Light Facility that worked on that principle, but I am not sure. I know that stream in their collider decreased over time (like minutes), but IIRC they re-fed it without stopping the whole thing, albeit in bursts.
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If you can spark it with the lasers, can you keep it going by feeding it with a collider?
 
Henning said:
If you can spark it with the lasers, can you keep it going by feeding it with a collider?
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No. People call it "burning," but it isn't like lighting a log in the fireplace.

Even if you could feed a collider continuously, target can't be. Inertially confined fusion depends on a fuel pellet getting compressed by a uniform implosion. That implosion is fed by lasers conventionally, and we did it with heavy ion colliders. Because it starts with a pellet, it's inherently pulsed.

Magnetic confined fusion (like Tokamaks) offered the promise of a continuous burn, but that has yet to materialize.

Obviously, it works fine in the Sun, using gravitational confinement.

You can feed a collider continuously IF you can keep a constant electrical field there to accelerate it. That has power implications, so these things are usually either low energy or highly pulsed. You also get one pass for a DC field, so it has to be a BIG one. If you try to accelerate past a DC field multiple times, you lose all the previous accelerations on the way around. What's typically done is that the electric field is oscillated at the same frequency the beams circulate, which makes them "bunchy." That way, you can get a kick as you go through the electrodes, get another kick on the way around the ring, then, get the same kick going through the electrodes again. But that's not continuous. Particles that are out of phase with the RF will get decelerated and lost rather quickly. That is, however, the essence of the original cyclotron design by Lawrence, and it is still heavily used. ALS uses a much more sophisticated array of oscillating electric and magnetic fields, but it's essentially the same idea. It gets a lot nastier when the particles get Relativistic, as the time dilation effect changes the RF frequency. You can see the compensation for that if you ever take a close look at the SLAC collider -- the acceleration chambers are longer further from the source. That makes it pulsed as well.
 
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So two weeks into my Thermo Nuclear Physics Course I decided that my math skills were not up to what was going to be required and dropped out.

But here is my layman's understanding of what a fusion reaction is. Essentially when some materials are highly compressed they release energy. This is how the Sun works due to it's huge mass it uses Gravity to compress hydrogen until it fuses and releases heat energy. So essentially the Sun is a huge Fusion reactor.

Our problem is that to do this on a small scale we have to use something besides gravity to provide the compression, this requires large amounts of energy to compress it. Not only that, but once compressed we need to be able to contain the materials at the high temperatures involved.

It's one of those things that seems like it should be possible, but has some seamingly impossible hurdles, sort of like trying fly 150 years ago. It's only not possible until someone figures it out.

Another interesting company is General Fusion. I liked the comment that spending money on hotel rooms and office equipment was frustrating when they really wanted to be spending it on development. They did finally replace the yellow sticky note on the door with a proper sign for the company. Someone had stated that their version was sort of the equivalent of a Thermo Nuclear Diesel Engine. I don't know it has any feasibility or not, but it is educational to consider how they are trying to do it.

Like I said I dropped out of the Thermo Nuclear Physics Class so much of this is likely just wrong. Correct as much as you see fit, perhaps I will learn something.

Brian
 
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