hmm....

I was just thinking about the fallout over the controversy of
the Clinch River Breeder reactor. Even though Reagan supported
the project, it was ultimately killed in the senate in 1983.

According to: http://debye.colorado.edu/phys3070/Lectures24-30.htm

"A reactor lasts about 30 yrs. Metal parts weaken when exposed to 
radioactivity."

Many of the older reactors are coming upon their 30 birthday..
and even if they lasted indefinitly. There is still the problem
of storing the waste they produce...I've read that the Big Rock 
Point Reactor closed down "due to waste storage limiations"

(src: http://ishgooda.nativeweb.org/nuclear/fermi2.htm )

I've been reading about this new NIF (National Ignition Facility)
at Livermore National Lab, which is suppose to be creating the 
world largest laser for testing Fussion...the problem is that
cost over-runs and delays, it was suppose to open in 2003 but now
is sceduled to open in 2008 if there are no other problems.


Anyways Twenty years later, it seems we've made very little 
progress. What do you think the future of this industry is?
How about the new pebble bed reactors? too much F.U.D? 

20 responses total.

The safety of the reactors themselves has never been an issue for me,
though I agree that things like pebble-bed reactors, which are
inherently safe in the event of coolant loss, are an excellent idea.  I
wouldn't feel uncomfortable living next to a nuclear plant that used the
existing technology, though.

For me the big question is still, "what do we do with the waste?"  The
Nevada site seems like the best choice out of a lot of bad options, but
it's not enough of a solution to really make me comfortable with the
idea of building more nuclear reactors.

I get the impression that the cost savings that reactors were supposed
to represent have never really materialized either, because of how
expensive they are to maintain and the cost of waste disposal.

The proposed commercial pebble-bed modular reactor near Cape Town SA is
causing controversy - over waste - before it is built. See
http://www.capetown.gov.za/press/Newpress.asp?itemcode=614

What do we do with the waste?  You recycle it, and the leftover bits are only
dangerously radioactive for 300-400 years.  What we do with our present
nuclear fuel cycle is akin to burning the bark off of a huge log in a
campfire, then throwing away the log.

I don't think most people can appreciate the advantage of waste being
dangerous for "only" 300-400 years.

That stuff is *intensely* radioactive, too -- very concentrated.  In some
cases it needs active cooling to keep it from melting itself down.

Given that the Japanese have had several nasty reprocessing accidents, I
*don't* think I'd want to live next to a reprocessing plant.

hmmm....I find that interesting...

if they spent fuel is so hot, why can't it still be used?

Isn't it just used to heat water into steam to spin a
turbine? seems like a waste of resource to me.

It is "hot" with radioactive isotopes. It is not so hot for generating
heat, which requires controlled fission.

Some of it is thermally "hot", too.  Some of the reprocessing done at
the Hanford site produced concentrated liquid waste that self-boiled.

That doesn't mean they were generating a great deal of heat energy. That
heat was produced by radioactive decay, not fission, and heat from
radioactive decay has only been useful in small, low power, generators. 

Re #4:  That's only because they've been brainwashed by propagandists
for so long.  When you contrast poisons like mercury and lead which
remain toxic forever, 400 years is a huge improvement.  So is the
million-fold reduction in volume over e.g. coal ash.  There are
wooden builings older than 400 years; the pyramids are 5000 years
old, and there are mines far older still.  400 years is nothing.

Re #5:  If you're interested in the actual cooling required, look up
"reactor afterheat" (in a CRC handbook, not Google).  The tables yield
the fraction of full-power output under different circumstances of
run time and time since shutdown.  (Active cooling isn't that big of
a deal, because it only takes a week or so for a reactor to cool down
to the point where its fuel can be changed; this means that the
coolant has to remain cooler than the boiling point of water.)

There are plenty of places in the US remote enough to not be "next
door" to anyone, and most of the Japanese problems seem to have come
from people failing to follow procedure.  This can be ameliorated
with equipment performing cross-checks and sounding alarms.

Re #6:  If you look at the afterheat tables, you'll see that the
minuscule fraction of operating power which comes from the fission
products losing energy simply isn't enough to be worth the effort
to capture (except for some very special purposes, like space probes
[Pu-238] or radiation sources [Cs-137]). 

Re #8:  Anything that produces heat can get to the boiling point, if
it's big enough and thus self-insulated.  Some of the Hanford wastes
"burp" gases unrelated to boiling.  AFAIK, these gases come from the
radiolytic decomposition of the organic solvents used to separate
uranium from plutonium (the SOLVEX process).  This is one nasty brew...

There are more modern reprocessing technologies which use molten salts
instead of the organics, and the horrendous mess which people associate
with reprocessing ala Hanford simply can't happen.

I still think that our response to nuclear waste should be to reprocess
it, vitrify the fission products into glass blocks, and stack a pyramid
of the blocks on a concrete or ceramic pad in our driest desert.  Done
right, it would glow gently from Cerenkov radiation.  You could let
people view it from a safe distance and use it to attract tourists.  The
only problem is that it wouldn't be a very big pyramid for a long time.

Oh, yes.  If any Al Qaeda or other group wants to crash an aircraft
into it, we should offer to train their pilots, sell them the aircraft
(at a substantial profit), see them off from the airport, and televise
the crash live on Pay-Per-View.  It should profitably finance the cleanup,
as well as being a wonderful example of the futility of their cause.

Thanks for the clarification. :)

EU Diplomats to Settle on Single Fusion Site
Wed November 19, 2003 02:25 PM ET

BRUSSELS (Reuters) - European Union ministers will propose a single 
site to its international partners in a pioneering project to create 
the world's first large-scale nuclear fusion reactor, a diplomat said 
on Wednesday.
 
Nuclear fusion promises to use the same energy that powers the sun to 
generate electricity without the hazards of conventional nuclear 
fission reactors.

But the technology has never worked outside a laboratory, and the EU,
United States, Canada, Russia, Japan and China are sharing the $11.92 
billion costs of building the first reactor.

Canada and Japan have already proposed sites, and the EU had originally
put forward two locations, one in France and one in Spain.

But diplomats from the EU's member states agreed on Wednesday that their
ministers would settle on a single site on November 27, one diplomat 
close to the decision told Reuters.

"They are going to say one site (at the) next competitiveness meeting," 
the diplomat said.

The bloc has not decided whether its proposed site would be in France 
or Spain. It was not immediately clear when a final decision among the 
international partners would be taken.

http://www.reuters.com/newsArticle.jhtml?type=scienceNews&storyID=3854545

I don't think that the technology has worked in the laboratory, where
by the technology working I mean that more useful power has been  generated
than has been consumed by the device. 

Hmm...so why build a larger scale one?  Is it because there are
inefficiencies that get smaller as you scale up, making it easier to
reach the break-even point with a larger reactor?  I suppose heat losses
would be easier to control on a larger scale, since you'd have less
surface area for the same volume.

I have only read that the proposals for larger devices, for the reasons
you give, would still be experimental, but with a hope of attaining
"breakeven" power generation. . 

In addition, it is false that a fusion reactor would not create
readioactive waste. The bombardment of the containment with neutrons will
create radioactive isotopes. It even uses radioactive fuel.  The only
demonstrated production of fusion has been with mixed deuterium and
tritium fuel. Tritiuim is radioactive. In proposed power reactors the
tritium would be made in place by converting lithium. 

Lots more info at
http://www.sciencemuseum.org.uk/on-line/fusion/reactors.asp, including
access to a Tokomak reactor you can operate yourself!

If I understand correctly, larger fusion machines are
"easier" to push to breakeven because the pressure gradients
are lower, causing fewer problems with plasma instabilities
and making it easier to get the higher confinement times
required to achieve enough fusions to recover the invested
energy.  I say "easier" because larger machines mean larger
magnets, which are both harder and more expensive to build.

Inertial confinement fusion is the same.  We can easily
make "reactors" with per-batch yields of tens of megatons
down to hundreds of kilotons, but fusing microgram or
even milligram quantities is comparatively very difficult.

I recall reading that we could have build a linear plasma
pinch machine that would have gone to breakeven at least
20 years ago.  The problem is that the machine would have
had to be roughly a kilometer long, to give the plasma
enough time to react before it squirted out the ends.

update on the NIF:

In a nutshell, the purpose of this is to try to simulate nuclear fusion. 
Currently four of the 192 laser beams are in operation. The new target
date for the first test is now 2010.

here's the full story: 

http://www.cnn.com/2005/TECH/05/23/super.laser.ap/index.html

Finally!

"A long and bitter dispute about where to site the world's largest
nuclear fusion reactor looks all but certain to end in favour of France.

Countries have been arguing since 2003 over whether to site the
International Thermonuclear Experimental Reactor (ITER) at Rokkashomura
in Japan or at Cadarache in France. The French bid has been backed by
the European Union, China and Russia, while Japan has been supported by
the US and South Korea.

Recent reports that Japan has accepted that the reactor will be built in
France are accurate, UK government sources have told New Scientist. But
officials are nervous about publicly confirming the agreement in case it
falls apart at the last minute.

The European Union stressed that no final decision would be taken until
ministers from all six parties meet in Moscow, Russia, on Tuesday 28
June. "We are optimistic that we will reach a decision on the site
then," said the EU's science spokeswoman, Antonia Mochan."

full story at: http://www.newscientist.com/article.ns?id=dn7573

which area is more earthquake prone?

Japan, but I don't think earthquakes are much of an issue. There is
no radioactive hazard to guard against with the ITER. I would expect that 
construction standards for the relatively small facility would take
earthquakes into account. Other issues are more important in deciding between
Japan and France. 

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