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From: dietz@interaccess.com (Paul F. Dietz)
Newsgroups: sci.physics.fusion,sci.physics.accelerators
Subject: Re: Put ITER and NOVA on ice; and all-out-attack on Sonofusion
Date: Wed, 13 Aug 1997 03:55:03 GMT

On 12 Aug 1997 23:51:35 GMT, "Carl Dean" <cdean99@mindspring.com>
wrote:


>Fusion has an advantage in that its radioactivity has a much shorter
>half-life and because of this should not invoke as much fear.  It also
>can't melt down, which is another advantage worth noting.

These claims are subject to dispute.

Halflife:  there can be very long lived activation products
produced in the wall, even with ostensibly low activation materials
like SiC (from 28Si --> 27Al --> 26Al, the last have a halflife
of 7.2e5 years.)  [Vanadium may be better, but is scarce and
somewhat expensive.]

Meltdown: with improperly chosen first wall materials, the time
from loss of cooling (and shutdown of the reaction) to melting
of the first wall (from decay of shortlived activation products)
can be only a few minutes.  Proper design and choice of materials
can avoid this, but then that's true of fission as well.

Fear?  Imagine what Greenpeace is going to do with a machine
that puts a blanket containing a megacurie of tritium next
to magnets storing the energy of a small bomb.  Also imagine
the fear of bondholders in a utility that tried to build
a tokamak, since that residual radioactivity is more than enough
to render the core inaccessible to hands-on maintenance.

	Paul

Newsgroups: sci.space.policy
From: Henry Spencer <henry@zoo.toronto.edu>
Subject: 3He fusion (was Re: After Station? (Outreach II))
Date: Fri, 29 Dec 1995 00:15:18 GMT

>If helium-3 fusion was perfected we would have clean nuclear energy.

Well... not entirely.  A D-3He reactor would still produce some neutrons,
because there are D-D side reactions which can't be entirely suppressed.
The problem *would* be much reduced.
-- 
Look, look, see Windows 95.  Buy, lemmings, buy!   |       Henry Spencer
Pay no attention to that cliff ahead...            |   henry@zoo.toronto.edu

From: bds@hagar.ph.utexas.edu (Bruce Scott)
Newsgroups: sci.energy
Subject: Re: What do Netpeople think about fusion?
Date: 15 Sep 1993 15:45:32 GMT
Message-ID: <277das$e3a@geraldo.cc.utexas.edu>

mvp@netcom.com (Mike Van Pelt) writes:

>Fusion has been "Real Soon Now" for so long that I've given up
>waiting for it.

In this we are still paying for the enthusiasm of people who in the
1950s paid no attention to the emerging science of turbulence, and
thought that the production of an MHD-stable magnetic plasma
confinement device would be sufficient to make fusion. You see, if
thermal and particle transport were really caused solely by
collisional diffusion, we would have been producing fusion for the
last 20 years or so.

Unfortunately, it is not like that. Small fluctuations in density or
temperature cause small electric field fluctuations, since the
electrons (with their smaller mass) tend to run away (along magnetic
field lines) from a compression much faster than the ions. Since the
processes are rather slow, the small electric fields generated by this
incipient separation hold the electrons back so that the electron and
ion densities are held equal up to a small correction. These electric
field fluctuations, however, give rise to small-eddy bulk drifting
*across* the magnetic field lines. Turbulence between these "E cross
B" eddies and the density and temperature fluctuations give rise to a
bulk transport out of the device at a rate which is much larger than
would obtain from collisional diffusion, particularly at high
temperatures.

Nobody even surmised this back in the 1950s when all the boy-wonder
propaganda was generated, and people have regrettably taken to
ass-covering rather than truth-telling. It continues today, when
worries over the ability of industrial materials to withstand the sort
of power loads they are going to get in a reactor are not discussed
outside our community. This is a mistake, in my opinion. But
scientists are not to blame for this, unless they submerge their
careful skepticism and make common cause with the Government
propaganda machine. Unfortunately, most of the encounters of the
general public with scientists are with this second sort, and a very
jaundiced and unjustified opinion of scientists in general on the part
of the general public results. Hence, all these "real soon now"
comments and the (predictable) reaction to them. Unfortunately, when
people like me tell the truth about theoretical confinement study ("I
can identify a physical process which I know is important from
comparisons to experimental observations, but because of the necessary
simplifications it is premature to discuss scaling laws, from this
theoretical model or any other.") we get brushed aside or ignored,
because there are any number of people who will beat their chests
("This code has *everything*." or "That issue is *settled*.") to get
attention and, yes, increased funding.

>Some statements I see here are addressed to specific fusion
>technologies, and are not applicable to others.  For instance,
>comments about the problems of high neutron flux are not applicable
>to aneutronic fusion, like 3He.  (Yes, it's harder to fuse 3He than
>other fuels, but since all products are charged particles, you can
>do direct conversion to electricity.)

This is unlikely. I assume you are discussing the reaction

	He3 + D --> alpha + p + 18.3 MeV

Unfortunately, you will get a number of secondary reactions

	D + D --> He3 + n
	      --> T + p		(50 percent branching ratio)

from which you will get some

	D + T --> alpha + n

with that big, bad 14 MeV neutron. For aneutronic fusion you need

	p + B11 --> 3 alpha

but B11 is exotic fuel and the cross section may be difficult
(unfortunately, the NRP Plasma Formulary does not tabulate it).

>My strongest conviction about fusion is that I am absolutely certain
>that if and when fusion becomes a practical source of cheap, clean,
>abundant energy, All The Usual Suspects are going to be all over it
>with "Fusion Kills" signs, chaining themselves to the gates, and
>locking it up in the courts.  Did you see Paul Erlich's editorial back
>when it looked like Cold Fusion was for real?  He denounced it as
>a disaster for the environment, sight unseen.

I'll worry about this when the time comes. Population-growth-induced
environmental problems will be all over us before fusion power comes
on line. Obviously, all those brilliant statements at last year's IAEA
meeting about how fusion is the hope of all those Third-World masses
who want Western-level energy consumption are pretty laughable.

--
Gruss,
Dr Bruce Scott                             The deadliest bullshit is
Max-Planck-Institut fuer Plasmaphysik       odorless and transparent
bds@hagar.ph.utexas.edu (to 12 Oct)                   -- W Gibson




From: bds@hagar.ph.utexas.edu (Bruce Scott)
Newsgroups: sci.energy
Subject: Re: What do Netpeople think about fusion?
Date: 15 Sep 1993 15:54:44 GMT
Message-ID: <277ds4$ehm@geraldo.cc.utexas.edu>

zowie@daedalus.stanford.edu (Craig "Powderkeg" DeForest) writes:

>Actually, this (the idea that fusion will be a nice, clean energy
>source) is a popular misconception.  The most likely plasma hot-fusion
>scenario is tritium-tritium or at least tritium-deuterium fusion, both
>of which produce scads of neutrons and lots of messy neutron-
>activation products, not to mention that they use tritium, which is a
>pretty hazardous radioisotope (hard to contain, and it *loves* to get
>into people, who are perhaps 1/3 hydrogen by nucleus count).

I think you mean "deuterium-deuterium or at least tritium-deuterium"
here. There is no energy gain from a T + T reaction. Your other
comments are correct, not least because in any credible scenario
(except p + B11, a big maybe) there will always be the reaction

	D + T --> alpha + n

with the 14 MeV neutron, at least as a secondary reaction.

In addition to tritium, some pretty exotic things have to be done to a
plasma containment vessel to keep the plasma at least reasonably free
of impurities (which pick up energy by excitation from collisions with
the electrons and radiate it away), and this involves toxic stuff.
(Whether it is the boron or what is used to apply the boron to the
vessel, I don't know.)

Moreover, we have to come up with a material or combination of
materials out of which to make the "divertor target plates" which have
to take up all the energy which comes out of the plasma. That involves
an industrial process which is probably not too clean, and plenty of
toxic materials.

Of course, other power scenarios have similar problems, but this is
just to counter all those "cheap, clean, limitless" statements.

--
Gruss,
Dr Bruce Scott                             The deadliest bullshit is
Max-Planck-Institut fuer Plasmaphysik       odorless and transparent
bds@hagar.ph.utexas.edu (to 12 Oct)                   -- W Gibson



From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: OT - Oil Bashing
Date: Thu, 02 Feb 2006 05:46:44 -0500
Message-ID: <40n3u1pem7l6ni1q1cv11rvtlts6s54l48@4ax.com>

On Thu, 02 Feb 2006 03:51:15 GMT, Rich256 <nospam@nospam.net> wrote:


>Remember back in the 70s when the government bending to the consumer
>came up with the old oil/new oil prices?  Those drilling and pumping
>from new wells got paid more than those from old wells.  Around here the
>owners of the stripper wells pulled their pumps and capped the wells.
>They couldn't afford to pump.  Maybe they might be going back to look at
>them again.  Governments can't understand why business can't operate in
>the debt like they do.

Yep.  There are two capped wells on some land I inherited from a rich
uncle.  I hear from my agent that there are inquiries being made about
those wells.  I'm all ears :-)

>
>Regardless there have not been any major new fields found in many years.
>
>I had great hopes for Nuclear fusion.  But after 50 or more years I am
>beginning to wonder if they will ever make it break even.  That was
>going to be the clean, safe power source to generate huge amounts of
>electricity and be able to make hydrogen in large quantities.

Won't ever happen, at least not hot fusion.  Back in my nuke days I
used to rub elbows with some of the scientists.  When the opportunity
rose to have frank talks, no one really expected much, only a method
to a career doing interesting experiments.

Assume for a moment that some method of controlling hot fusion well
enough to produce economically useful quantities of power - in the
megawatt range.  That myth of "clean and safe", especially compared to
fission, is just that, a myth.

First off, to shed megawatts of power, much more energy must be
contained somehow in the hot compressed plasma.  A failure in the
containment would release this energy and the release would be bomb
quality.

Second, the majority, something like 90+% of the energy released in a
fusion reaction is carried off by very energetic neutrons in the 14MEV
range.  This is quite unlike fission where the energy is carried away
as fast moving (re: hot) fission fragments.  With fission, radiation
is only incidental.  The fission fragments quickly transmit the energy
to the surrounding material as heat via collision.

Neutrons are different.  They'd be slowed and then absorbed in a
lightweight material to be converted to heat.  Particles this
energetic would require much absorber.  Water would probably be used
but it would require containment.

The flux from a megawatt-sized fusion reactor would be on the order of
that in a thermonuclear bomb at the moment of detonation, dense enough
to have significant mass and very destructive to any materials in the
path.  Ordinary steel is quickly made brittle as glass by such
bombardment. One of the main purposes of the High Flux Test Reactor
was to investigate materials that might withstand that sort of flux.

Beyond the destructive effects of the high neutron flux, it would make
anything in the path very highly radioactive.  Even trace amounts of,
say, cobalt and nickel in the steel would be activated to become VERY
hot, much hotter than materials used in fission reactors where the
flux is many orders of magnitude lower.

Most any fusion reaction that has any hope of ever working produces
tritium in the process.  Lots of tritium.  Tritium will also be one of
the fuels.  A breeder, so to speak.  Tritium is radioactive, though
the emitted beta particle is so weak as not to be of much concern.

The problem is, tritium, hydrogen, is a bitch to contain, especially
in the elemental form used in fusion reactions.  It easily diffuses
through steel and other common materials.  Any environment where
tritium is used in quantity quickly becomes widely contaminated with
the stuff.  The tiny production of tritium in conventional fission
reactors drives the operators nuts because it is so difficult to
contain.  I can only imagine the problems involved in trying to
contain kilograms of tritium at a time.

I should note that tritium is considered a special nuclear material,
controlled like plutonium and enriched uranium.  The same fringe
non-proliferation types who go nuts over the "proliferation risks" of
the small amounts of plutonium in spent reactor fuel would logically
have a cow over huge quantities of tritium that would be involved.
While I don't take the Pu and eU claims seriously, those who do would
logically have to squawk about the T.  So much for safe and clean.

The fact of the matter is, it'll be hard to get any safer or cleaner
than conventional nuclear power as practiced by the free world.  I add
the latter to separate us from the Crazy Ivans and their uh, reactors.

While the hysterics have screamed and flailed about, we've gone about
quietly generating terawatts of clean and safe power.  We've proven
over 50+ years that the relatively small amount of radioactive
materials involved can be safely contained.  If you whip out your
handy-dandy gamma spectrometer, the tiny amount of artificial
radioactivity you find in nature is the remnants of atmospheric
weapons testing and not nuclear power.  One can tell the difference.

Maybe the time has come for the pendulum to swing back to nuclear
power.  There really isn't any other choice if one desires to reduce
fossil fuel consumption.  I hope I live long enough to see a mini-nuke
in every neighborhood.

John


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