Wayne wrote (he may be quoting Glenn).
>
> To go back to the main thrust of Glenn's post:
> Probably fusion is a good suggesting since it doesn't create the waste
> characteristic of fission reactions. It also does not dirty the atmosphere
> with CO2 and NOx which is also a matter of concern.
>
A couple of comments from a "reformed nuclear engineer" (someone who
used to be a nuclear engineer but has since seen the light and changed
his ways). I am about 15 years out of the loop so some of what I say
may be treated skeptically. Lest my deprecation be taken too
seriously, I would, however, not have qualms about living next to a
nuclear plant, at least compared to a number of other options (fossil
fuel plant, industrial plants, etc.) I left because I found physics
more interesting.
First, fusion reactors (as opposed to reactions) do produce
significant radioactive contamination through activation. The very
high energy neutrons (14 Mev) present a challenge to the person trying
to convert the energy of a neutral particle into electricity, and to
find shielding that will stop the neutrons and not fall apart. This
shielding whatever it is will be highly radioactive after it is
finished. The half life of the shielding radioactivity will be less
than that of plutonium but still significant (I believe we are talking
hundreds of years).
Second, my gut feel as a fairly well-educated lay person (masters in
nuclear engineering, Ph.D. in physics) is that workable nuclear fusion
is highly improbable. I recall talking to a nuclear engineer in the
company I was working for back in the middle 70's, who's comment about
fusion was that they had been saying for a quite a few years that
there were just a few more "little" problems to work out. The gist of
his story was, "Don't believe what you hear---the problems were
cropping up faster then they were being solved. At that time the
predicted time from present until viable fusion was always a constant
20 years (I recall seeing 2000 as the year predicted for fusion
power). Now according to Glenn it is out to 40 years.
Is this just a social problem or a public policy problem? If we throw
more money at it, could we make it work? I think not. The crux of the
problem is that you are trying to contain very dynamic electrically
charged particles (a plasma) electromagnetically (laser induced fusion
is somewhat different). The containing fields change the motions of
the particles, which changes the electrical and magnetic fields
produced by the plasmas, which changes the electric and magnetic
fields needed to optimally contain, etc., etc. Solar storms give a
hint of the difficulties of containing plasmas and the difficulties of
controlling instabilities. In mathematical or physics terms, it is a
highly non-linear problem. Non-linear problems are extremely difficult
to solve or to predict.
My skepticism has, in part, been picked up from people who were
working in the field.
------------------------------------------------------------------------------
Joel W. Cannon | (724)223-6146
Physics Department |
Washington and Jefferson College |
Washington, PA 15301 |
------------------------------------------------------------------------------
Joel W. Cannon | (724)223-6146
Physics Department |
Washington and Jefferson College |
Washington, PA 15301 |
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