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FW: [cdn-nucl-l] Nuclear energy is environmentally friendly: Handout on radwaste



I also like Ted's factsheet. 
However, I think the statement about fuel consumption should be made clearer.  As it is, it may be considered as being deceiving.
Let's assume we're talking about a 1,000 MW(e) LWR.  Its thermal output is about 3,000 MW(th), and in one year it produces about 3,000*365= 1.1*10^6 MW.d of fission energy.  If the burnup is assumed to be even 40,000 MW.d/Mg(U), the amount of fuel going through the plant in one year is 1.1*10^6/40,000 Mg(U), ie., about 25 Mg (tons) of uranium [and, by the way, the amount of mined uranium would be several times this amount].
No matter how much of the uranium actually fissions, most people would consider that the plant has consumed 25 tons of uranium.  Unless the fuel coming out of the reactor is re-used essentially right away and in an easy way (which for the most part it isn't), it is piling up as spent fuel and most people would indeed consider that the amount of uranium consumed is 25 tons. 
Thus the statement on fuel consumption should really say 25 tons, not 1 kg or a few kg.  A subsequent sentence could say that much of the fuel coming out of the reactor could be recovered and eventually re-used.  This way the statement is correct all around.
My suggestion, anyway.
Again, I like the factsheet and think it is very useful.
 

Benjamin Rouben
Manager, Reactor Core Physics
AECL Sheridan Park
Tel: 905-823-9060 x 4550
Fax: 905-822-0567
e-mail: roubenb@aecl.ca <mailto:roubenb@aecl.ca>
Cell: 905-302-2054

-----Original Message-----
From: Jerry Cuttler [mailto:jerrycuttler@rogers.com]
Sent: 2002/mm/13 5:04 PM
To: cdn-nucl-l (E-mail)
Subject: [cdn-nucl-l] Nuclear energy is environmentally friendly: Handout on radwaste

Dear George,
 
The actual amount of uranium "burned" or fissionned is only a part of the U-235 content.  A very small amount of the U-238 is transmuted into plutonium, and ~40% of that is "burned" in an LWR.  The rest of the uranium is not consumed.  So that's where he gets a kilogram.  The "unburned" uranium should not be considered waste.  Future generations will likely recycle it, if we don't make it too difficult to recover.
 
Jerry
----- Original Message -----
Sent: Sunday, January 13, 2002 1:24 PM
Subject: Re: [cdn-nucl-l] Nuclear energy is environmentally friendly: Handout on radwaste


Ted Rockwell has produced excellent fact sheets. 

Just one quibble:  I think a 1000-MWe reactor would burn about one metric ton of uranium per year, rather than a kilogram (still, that's to be compared with ~3 million tonnes of coal).  Rule of thumb: fissioning 1 g of atoms liberates ~1 MWth-day of energy.  Thus 1 kg would produce 1 GWth-day, or about 0.33 GWe-day.

I hope this word somehow gets back to Mr. Rockwell.

                George Stanford



At 08:54 AM 1/13/2002 -0500, Jerry Cuttler wrote:
Here is accurate information we could use in Canada also to explain why nuclear energy is environmentally friendly