Fusion, Politics and Thermodedgummits!

Reflections on fusion history, current events, and predictions for the 'fusion powered future.
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dabbler
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Fusion, Politics and Thermodedgummits!

Post by dabbler »

While reading the stuff the Big Labs(tm) put out, I discovered that they
are fascinated with the idea of producing thermonuclear fusion in their
reactors. One of the folks over at Los Alamos bragged that his lab
was the only lab to have _ever_ produced _thermonuclear_ , he
placed great emphasis on "thermonuclear", fusion.

Uh-huh. Look, Bubba, we don't care about thermonuclear fusion.
What we are after is power. Get it? P-O-W-E-R. Power. I am not
trying to destroy a city or burn up an entire state. I just wanna run
pumps and light bulbs.

I don't need and don't want to fire a boiler with thermonuclear or heat
from any similar source, either. That's a waste. If that's the best we
can do, then let's blow this fusion business of and start looking
powersats and improved fission plants. I can fire a boiler with gas, oil,
coal, fuel, and even the moonshine ADM wants to put in you gasoline.
Not only are boilers old hat, they're wasteful.

The real money to be had from fusion, if there is any to be had, is
going to come from converting the energy in the alpha particles into
electricity. The second big block of profit comes from converting x-
rays into electricity. After that, it's capturing energy in fleeing
neutrons. At the very bottom is waste heat recovery and there will
likely be quite a lot of that in any fusion plant that works.

Okay, so why the fascination with thermonuclear fusion? Because of
the density, right? But do we really care about density? No, not really.
What we care about is how much energy coming out of the system
versus how much we have to put in to get the reaction started.
Density, at first blush, seems to be the most likely way to get the
output/input ration where we want it. It hasn't worked. We've been
working on it since about 1953 and we've spent tens of billions of
dollars and we have yet to achieve a sutainable fusion reaction that
way.

It's time to try another approach. The one method we have used that
actually produces sustained fusion reactions is the one being used in
these little fusors. It's time to focus on refining that method and stop
throwing money into a hole in the vacuum.

But that isn't going to happen on a spare time/spare change budget.
The best we can do is nibble around the margins with this approach.
There _are_ some valuable things we can do, such as seeing if there
really is a workable method of capturing the energy of alpha particles
in the form of electricity. We can start testing materials in hopes of
finding one that does a good job of converting x-rays to electricity. We
can also do what Larry has been doing and start looking at ways to
take advantage of the neutron flux. It would be even better if we could
find a way to take advantage of neutron decay while were about it.

I think that finding a way to get collision numbers up into the break-
even range is going to be out of our reach without some serious
investment. The way to get that investment is to show proof-positive
that the energy can indeed be captured once it is produced and be
captured WITHOUT steam being the chief means of conversion.

Until the promise of fusor type plants is made bright enough, there
won't be any investment. If we can demonstrate that the energy can
be recovered efficiently with a minimum of extraneous activation, we
can go the Venture Capitalists and ask them if they want to make a
bet. I guarantee ya, some of 'em will take the bet.

dabbler.
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Richard Hull
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Re: Fusion, Politics and Thermodedgummits!

Post by Richard Hull »

I think that if a fusion device could be made that was filthy with activation and demonstrate over unity output it would obsolete every fission plant overnight. Such a source of energy gain instant acceptance.


There is not even the slightest glimmer of hope for this though in all of the ideas, in all of the heads on this orb. Those in the know and who aren't looking to continue the work to keep their kids in school and buy that new home, will sadly admit there are zero contenters standing eagerly at the gates awaiting funding.

There is, however, a cadre of "the ever faithful", made up of knowledgeable people within the field, savvy lay folk, and the unwashed illiterate, seeking and trying to "wish" power-ready-fusion, at the hands of man, into existence.

I float in the middle. Knowledgeable, having done fusion personally, having studied the past work, keeping in touch with present work and out of it all, feeling it just won't be done in the hot or the cold at a large net gain that will feed wall outlets.

I sometimes think of myself as a Simmon Newcomb, saying man will never do this or that. (which he ultimately did).

I really believe and know that fusion will be done at some point in the future. I just believe the right idea, by the right genius, nutball, or lucky donkey hasn't even approached the playing field yet. Barring the lucky donkey, I think it is a long way off yet.



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
davidtrimmell
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Re: Fusion, Politics and Thermodedgummits!

Post by davidtrimmell »

dabbler, well you sum it up pretty well, especially for a boilermaker type ;-) But I did want to know how you would expect to get any usable energy from X or Gamma Photons? Look at the "mean free path" of 50-100 KeV photons and you will see that energy deposited in matter is pretty low. Now charged particles are whole different story...

Regards,

David Trimmell
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Re: Fusion, Politics and Thermodedgummits!

Post by dabbler »

Perhaps its simple-minded ignorance on my part, David. It seems to
me that if you put enough P-N junctions in front of the X-rays, they'll
rattle around inside them and create electron-hole pairs as they zip on
through. Is the glass half full or half empty? It might be half empty for
all I know. I'm not up to doing the math most of the other folks on this
forum can do in their heads.

But, surely you can see the overall picture I'm pointing to here. If we
cannot recover the energy from the alpha particles and x-rays, there
is no point in dancing with the demon in the bright blue dress because
all she is ever going to give us is hot and bothered helim along with a
few x-rays. Nearly all the money we spend on fusion, irrespective of
the method we use, results in these two forms of radiation.

If we cannot achieve these two goals, then let's fund just enough
research on fusion to keep a few astrophysicist happy and start
looking for other energy production methods that might hold greater
promise. I cannot overemphasize how important this is. Every dollar
we spend on oil is a dollar given to someone who will eventually try to
use that money against us. It is foolishness of the very worst sort.

dabbler.
3l
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Re: Fusion, Politics and Thermodedgummits!

Post by 3l »

Hi Dabbler:

I have been bombarded by emails from "Knowledgable" folks on fusion. Most are trying to gather Alternate energy schemes on the poor public put them on a cdrom and sell them for $14.99.
The public is scared spitless and in come the carpetbaggers to clean up.

Happy Fusoring!
Larry Leins
Fusor Tech
davidtrimmell
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Re: Fusion, Politics and Thermodedgummits!

Post by davidtrimmell »

Well dabbler, it certainly isn't "simple-minded ignorance" on your part, but I wouldn't bet the house on finding anything as efficient as PV cells for X-Rays. I am in total agreement with you regarding getting away from the petrol, that’s a dead end road in more ways than one. I think finding a good clean renewable energy source is just half the picture, the other half is using it efficiently. Currently we waste energy in a criminal manner. But I see energy efficient technology as a reality now, we just need to put more $$ into R&D to keep moving forward.

Regards,

David Trimmell
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Re: Fusion, Politics and Thermodedgummits!

Post by dabbler »

I've looked at several of these alternate energy schemes and I've
looked at conservation. Nothing in either field gets us there from here.
I do understand that we could do a better job in the realm of energy
usage, but that is not something the government can successfully
coerce. Remember the good old double-nickel?

Production of energy is a big part of the answer to this problem.
Conservation alone will not answer the need. Oh, sure, I could put my
own little boiler together and run it only as needed. I could even fuel it
with grass clippings picked up on the side of the road. That won't
produce the silicon needed for your Wintel box nor the polymers. It
won't make the concrete for your driveway nor will it get you to and
from work. The public has good reason to be scared.

So, we are right back to the same old question. Is fusion, by any
method or reaction, a worthwhile bet? I'm still trying to figure that out.
In other words, what are the facts and to how many decimal places?
You can't ask someone to put their money on the line until and unless
you can say in good conscience that there is at least a fifty-fifty
chance they'll get their money back along with a profit. Unless of
course, you happen to be a politician. I ain't one of them.

At least now I'm beginning to figure out what questions need to be
asked. As for the x-rays, I wouldn't have brought up except that it
seems they an be stopped by the appropriate materials and they
create voltages when they go through certain kinds of materials. So
there is good reason to think that there must be a material that will
draw electricity out of them as they run through. Trouble is, we
haven't looked for one, have we?

dabbler.
Starfire
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Re: Fusion, Politics and Thermodedgummits!

Post by Starfire »

As one of the ever faithful and unwashed illiterate I always note that there has not been any great improvement in the IEC Fusor since Philo dreamed it up, a bit like the reciprocating engine which is now over one hundred years and no great improvement.
What excites me is that there is so much potiential with this idea and it is available to me and all the other ' floaters' and unwashed illiterates. To crack this requires some lateral thinking and I think that this may be the place to find it - the place is just full of cookies :)
Lastly I am reminded of the notable ' scientist ' ( a fellow of you know what society ) from a century ago, who said that 'mankind should concentrate on technology, as all that could be invented had been by 1890 '. Politics - what is that, a state of mind or a mental state ?
dabbler
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Re: Fusion, Politics and Thermodedgummits!

Post by dabbler »

Given the hoopla we've been treated with so far this political season,
John, I'm forced to conclude that it is definitely a mental condition.

David,

Here's another reason I'm a bit more optimistic about the x-rays:

http://www.bpmlegal.com/6385291.html

Iffen' we can focus 'em, we can do all kinds of things with 'em. It's a
matter of deciding that we will. I started wondering about this back
when we lofted this thing:

http://chandra.harvard.edu/

I think that in the end, we'll find that PV cells tuned for the upper end
of the spectrum are a heck of a lot more efficient than the ones we
use for visible light.

That still leaves me wondering about how to make the alpha particles
pay their taxes.

dabbler.
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Richard Hull
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Re: Fusion, Politics and Thermodedgummits!

Post by Richard Hull »

I think we can forget having a politico ever take a firm energy stand beyond passing out a band-aid for a sucking chest wound. The nambie-pambies want green energy that is free and pretty. The old liners want ever increasing megawatts to fuel larger SUV like consumer goods and the public always goes with the flashy products and are bent on keeping up with the guy next door. The media tells us what's cool to have and use and who we should vote for.

A goodly dose of energy rationing via home watt meter controls centrally activated by the power utilities due to government legislation, would wake everyone up real quick.

Until the public takes this seriously and not just as a wine and cheese social subject, zippo will take place. I am sure that the government will bite the bullet first with energy rationing and then will come the knee-jerk public reaction. Politicos heads will roll and a new breed of politico will replace the old lies and promises with the new lies and promises. ( a very minature taste of this came in California a few years back)

Altering the entire social conscience and energy based infrastructure of a smoothly functioning, technologically advanced society near its malthusian climax will just not occur in ordered stages, but in a nasty, social upheaval.

Fasten your seat belts folks.

PS.

If anyone here feels that they are genuinely unwashed illiterates that is their own internal issue.

I would think that every soul here is

1. Familiar with fusion priciples.
2. Have studied it a bit.
3. Are under few illusions as to the realities involved.
4. Know the various forms of fusion available.

The above would certainly not class anyone as an unwashed illiterate.

If they still choose to believe in the fusion dream, they are at least well informed and cogent onlookers with positive attitudes.


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
davidtrimmell
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Re: Fusion, Politics and Thermodedgummits!

Post by davidtrimmell »

dabbler, I am not sure about that patent.

But even if it works I don't know where it gets us. Here is an example:
Ok 1 RAD = 100 ergs/gram. So let us assume we have a source of 10,000 RADs/hour (pretty hot source). In that field of X or gamma (>50kev) you will be depositing 3.6 watts into one gram of matter every hour. Now lets go further and say we are using 1000 grams of our miracle semiconductor to extract electricity from our x-ray field, that comes out to 3.6KW/Hr. Now we need to determine the efficiency, from memory (hey, this is all from memory so hopefully I am not making a total fool of myself!) the HPGe (high purity Germanium) detectors are usually less than 10% (now this is *detection* efficiency, not efficiency in producing electrons), but we will be generous here and assume 10%. So we now have 360 watts/hour. I don’t know about you but that isn’t going to get us vary far. Really, the only way that has any hope to me is the possibility of extracting the energy from the *charged* particles…

David Trimmell

PS. I may have goofed my math, but I know I am with a order of magnitude or so. This is also the reason why the electric generators in spy satellites, etc. using Pu-238 are only utilizing the thermal heat, converting that to electricity using thermo-electric generators.
dabbler
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Re: Fusion, Politics and Thermodedgummits!

Post by dabbler »

Just for the sake of exercise, what's the yield/gram on silicon PV's at
the expected fifteen percent efficiency using visible light? Drat! I gotta
go find the wattage/m^2 for sunlight. I'll be back.

dabbler.
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Adam Szendrey
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Re: Fusion, Politics and Thermodedgummits!

Post by Adam Szendrey »

1,4 kW peak, must be around 1 kW average.

Adam
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Re: Fusion, Politics and Thermodedgummits!

Post by dabbler »

The figures I found were all over the map, but the site that seemed to
actually understand math says that it runs 930 watts / m^2. I make
that out to be about 140 watts/m^2 converted power in ordinary PV
cells, assuming that they are very good ones.

A running fusion plant would operate 7 days/wk, 24 hrs/day. You don't
get that from sunlight. I also think that PV tuned for x-rays will turn out
to be far more efficient than 10%. The reason being is that you get
more than one chance with x-rays. In other words, the geometry is as
important as the material. Check out how Chandra works.

dabbler.
davidtrimmell
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Re: Fusion, Politics and Thermodedgummits!

Post by davidtrimmell »

Dabbler, I am not sure you get my point. Just try and back calculate how much energy is being produced by *FUSION* to get the x-ray flux I imagine?! I have been quite the Liberal here, but you will be spending dollars to save a couple cents of wasted energy. Worry about getting a real net even energy consumption before trying to salvage the wasted x-ray photons!

Personally I do not think Fusion will ever break even in a homocentric sense. We cannot emulate the stars, but we can be more creative. Perhaps we will find a "sustainable" way to push the cart up the hill, but we will still have to push it up there...

Regards,

David Trimmell
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Re: Fusion, Politics and Thermodedgummits!

Post by dabbler »

How much energy would that be, David? You see, I don't know. All I
know is what I've read and what I've read says that nearly fifteen
percent of the energy shows up as x-ray or gamma radiation. That's
not trivial.

Perhaps what I read was in error. I don't disagree with you that the
real gain comes from the charged particles, but fifteen percent is
fifteen percent and the more energy we are talking about, the larger
that fifteen percent is. Is the fifteen percent figure in error?

I am, of course, talking about ground applications here, not aircraft or
spacecraft. In a spacecraft, you'd accept that fifteen percent loss
without blinking provided you were well over break-even on other
outputs. You would do that to save on reaction mass.
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Richard Hull
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Re: Fusion, Politics and Thermodedgummits!

Post by Richard Hull »

What form of fusion are you discussing? I assume D-D?

If done well, there are no gamma rays or x-rays in D-D fusion. The fusor has a high waste of X-rays in D-D, but that is not due to fusion itself, just lost electrons slamming into the outer shell. The x-rays are isotropic and as such, 100% are automatically spent as heat in the outer shell up to about 50kv. Above that, they radiate outward. To capture those over 50kev would be a job in the sense of converting them back to electricity directly.

Compton scattering and the photoelectric effect would get electrons back in the mix which could be scooped up but conversion efficiency is below 10% as power efficiency goes.

Dave was right, Nothing beats thermal to electric conversion even to this date for compact, inexpensive and simple systems that are actually installable and in use. Most radiant energy to electricity systems are not happy with the nasty high energy photons. The devices that convert such energy are usually very expense or exotic and are made only in the small to keep costs down.

Thermal conversions work so well due to the thick absorber which can be dirt if need be. This absorber warrants that 100% of the photon's energy will be given up with zero losses as heat in the medium. Converting that heat to electricity, unfortunately is not so sweet, as thermoelectric conversion is crappy.

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
dabbler
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Re: Fusion, Politics and Thermodedgummits!

Post by dabbler »

Well, like you said, Richard, "Reseach is what I do when I don't know
what I'm doing."

I'm learning a lot around here, thanks.

dabbler.
JoelMoses
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Re: Fusion, Politics and Thermodedgummits!

Post by JoelMoses »

Question woud a high pressure, high temperature plasma stop X or Gamma Photons.
3l
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Re: Fusion, Politics and Thermodedgummits!

Post by 3l »

Hi Dabbler:

It only hurts for a minute....just scream and go on.

Happy Fusoring!
Larry Leins
Fusor Tech
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