Latest from U of Wisc. fusion output > 1mW

It may be difficult to separate "theory" from "application," but let''s see if this helps facilitate the discussion.
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sluce
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Latest from U of Wisc. fusion output > 1mW

Post by sluce »

On July 1st Ross F. Radel wrote...
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We have just recently broken a milliwatt of fusion power by running D-3He at 140 kV and 48 mA. This translates to 3.5E8 protons/s at steady state. This gives us a Q, or power out over power in, of about 1E-6.
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Ross is on the U of Wisconsin IES fusion team.

Only 6 orders of magnitude to go...
Go Team!
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Richard Hull
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Re: Latest from U of Wisc. fusion output > 1mW

Post by Richard Hull »

That is very nice, indeed. They spent a measley 6.7 kilowatts and got a whopping 1 milliwatt. go team, indeed. Still, an efficiency of 0.00001% is pretty good by our past standards.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Re: Latest from U of Wisc. fusion output > 1mW

Post by teslapark »

Hey, does anyone have the data for how much power the "Mark 2 Prime" was consuming when it produced 10e13 neutrons per second? I have always wondered this.

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Re: Latest from U of Wisc. fusion output > 1mW

Post by Richard Hull »

Gene can't remember the exact figure, as I have tried to get him to remember. But he said it was on the order of 4kw.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Re: Latest from U of Wisc. fusion output > 1mW

Post by ijv »

Out of interest, does anyone have any numbers on how the best conventional fusion efforts would compare?
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Richard Hull
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Re: Latest from U of Wisc. fusion output > 1mW

Post by Richard Hull »

Reports are varied and most are popular press accounts. Break even has supposedly been achieve for varying periods of time up to nearly 1 second according to popular press releases.

Break even refers to producing as much power from fusion as went into its production.

However no realistic scientific account has been handed down to the general public on the energy accounting procedures in such operations where such bold claims are made. Usually the claims preceed a funding cycle.

In an electrostatic fusor it is rather easy to figure enrgy in vs. energy out. However in a tokamak or other giant facility there are so many subsystems gobbling up energy at prodigious rates that there is no way even the finest device has approached true break even to within 4 orders of magnitude, I am sure!! Do you really think they figure in electricity to produce the magnetic energy need to contain the plasma? NO They figure the actual plasma generation energy, much like we do. Believe me, the plasma generation energy is a tiny fraction of the multi-ton magnet energy that they, I am sure, just don't mention in their calcs.

Another key item is that the reason they can't run more than a few milliseconds is that the chamber is ablating and crap is ripped off the interior walls during the pulse. In addition the confinment buckles and fails creating an end of event situation.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Re: Latest from U of Wisc. fusion output > 1mW

Post by guest »

A fusor is about a billion times more effective than a tokamak and about a trillion times more effective than the pellet fusion effort on a per power basis . To give you an idea how well this stuff stacks up against an H -Bomb in it's present state its about only ten to twenty times more effective. Which is to say it's got a long way to go. Just remember in our fusors we are dealing with a reactive mass about a 20 million times less than a bomb's fuel load. In a twenty megaton device the fuel that actually burns before containment is breached is about a kilogram,the rest is scattered in the plasma. Considering that the A-bomb trigger only burns the urainium equivalent in the dimensions of a penny. About 95 % of the potential energy is wasted at detonation. In this expensive clumsy way does fusion ever get done. Fusors are doing fabuluosly well compared with the also rans. On a cost per neutron basis the Tokamak runs about $100 a neutron
( Think I'm being unfair... I rounded down in their favor.
I simply took the reported GAO budget figures for the 10 years of the Tokamak funding so far and divided by the reported power figures... not pretty)
, WE CAN'T count the bucks that the laser fusion fusion effort has devoured .... $$$$? a neutron.

So lets do some Enron style accounting here.
Lets say a fusor rig costs 5,000 dollars.
Lets say you chew up 10 kw of juice.
Lets say you need lots of beer and chips.
For a final total of 6 grand.
Lets say 150,000 neutrons is the best production so far.
6000/1E5 works out to about .06 dollars per neutron.
or 6 cents per neutron. If costs could be reduced to (whoops! the table I was using was in 1x10^-3 mills... corrected value to follow.) .000002 to .000003 cents a neutron you start to get price competative with low scale fission. The best part is the equipment can be used again. Definitely unfair to the current fusion guys.

Happy hunting!
Fusion is fun.
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Re: Latest from U of Wisc. fusion output > 1mW

Post by cassius »

Umm...Larry - Nuclear reactors generate power at 1-2 cents/kWh, and I suspect that doesn't come out to 20 neuts/sec.

IMHO
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Re: Latest from U of Wisc. fusion output > 1mW

Post by guest »

I was speaking about a very small critical reactor .
Say like a school would use. 100 kw or less.
I realize the figures you are quoting... That only applies to large scale reactor systems in the megawatt range. Like Arkansas Nuclear One (10 MW). Small scale nuclear isn't so thrifty. In a teaching reactor the criticallity is highly dampened in order that
students won't create a run away condition. Triga reactors and small scale Flat plate reactors under 100kw have neutron costs in the range I quoted.
At one watt which is all the power a junior nuclear
power engineering student is allowed to generate the neutron flux is on the order of 7.59 x 10^ 13 per second.
Due to small core size these machines lose about a quarter of all neutrons produced.
I picked this as a long range goal as a target for fusion buffs to shoot at.

The fusioners would be throwing their hats in the air if we even came close to the numbers of neutrons that even these lowly reactors produce.

Larry Leins
Physics Teacher
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