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Electricity production costs drop to the lowest point in the industry's history.

You won't hear this on CNN, but the U.S. nuclear power industry set a record last year.  Despite rising costs of fuel and regulation, the average production cost of electricity dropped to an astounding 1.66 cents per kilowatt-hour.  This is a figure well below the cost of coal-generated electricity, and a tiny fraction of the cost of solar or wind power.  Furthermore,  nuclear plants generated 36% more electricty than they did 15 years ago, without a single new plant being built.  The industry just keeps getting better and better.

Nuclear power is a true clean, green energy source, with zero CO2 emissions, and less environmental impact than solar or wind.  Those sources of energy are extremely diffuse--which means they must be collected and concentrated.  A 1,000 MW solar plant requires 2 million tons of concrete, 600,000 tons of steel, 75,000 tons of glass, 35,000 tons of aluminum, and a whole host of rare and exotic elements.   This is several hundred times the materials needed by a nuclear plant the same size.  And the nuclear plant will have much higher availability and require much less maintenance.  Most telling of all is the costs which, for solar power, currently average a painful 28.6 cents per kW-hour.

Other nations are wiser here than the US.  France  generates 76% of its power from nuclear, South Korea has several new plants on order, and Finland is building a new one, specifically to meet its commitment to the Kyoto Protocol.

Expanding the US nuclear power industry would allow the US to dramatically reduce carbon emissions ... and to save money while doing so.  And it's a solution available today, without the need for years of additional research and development.  Its high time we pulled our heads out of the sand, and started using it to its full potential.



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RE: No argument here.
By exdeath on 3/1/2007 2:31:25 PM , Rating: 4
Uhm you guys have serious misconceptions...

"Depleted uranium" is natural uranium stripped of 99.99999% of its U-235 isotope so that all that remains is the stable non radioactive U-238 isotope. Depleted uranium is not radioactive, save for insignificant trace quantities of whatever U-235 remains after refinement. Natural uranium as it is only contains about 0.7% U-235 by mass. For all intents and purposes, depleted uranium, that is, the U-238 waste remaining after refinement, used in munitions for its higher mass density, is no more dangerous or poisonous than any other toxic heavy metals such as lead or mercury.

Spent fuel rods on the other hand are not ‘depleted’. Fuel rods result from refining natural uranium until they contain about 4-5% by mass of the U-235 isotope, the radioactive kind. This is far more radioactive than natural uranium’s 0.7%. When the fuel rod is ‘spent’ it only means it is not putting out sufficient energy to power the reactor, it doesn’t mean all the U-235 has decayed completely. So ‘spent’ fuel rods are still retain dangerous concentrations of U-235 so you cannot use this as ‘depleted uranium’, however they no longer serve their purpose as sufficient fuel.

What I don’t understand however, is why we don’t return and recycle spent fuel rods back into the original refining process. You could extract the remaining U-235 from piles and piles of spent and consolidate it into a higher concentration to make new fuel. I.e.: take the bad part out of the spent fuel, add it all together to make new fuel which stays in a reactor. What is left over then becomes depleted and safer.

The problem with that is that years of bombardment by neutrons, and the fission process itself, creates an assortment of other elements that taint the pure uranium. What starts out as pure uranium (4% U-235 and 96% U-238) is now a random glob of just about anything on the periodic table, some of them radioactive in their own right and useless as a fuel.

We could still refine and separate all those elements and put them to uses in places (cesium in the medical industry, etc). Costly, but better than storage for 1000 years.


RE: No argument here.
By exdeath on 3/1/2007 3:14:11 PM , Rating: 2
Just to refine a few things (no pun intended):

As per my previous post a new fuel rod goes in with 96% harmless U-238 and 4% U-235, which is the active fuel.

After 20 years of fission in a reactor, what is left is still mostly 90-95% harmless U-238. A tiny bit of that will have been transmuted to Pu-239, which can be used as reactor fuel itself.

The primary waste components are the fission products of the actual 4% U-235 fuel component. Remember that fission is simply the splitting of an atom into two or more other random elements, giving off useable heat energy in the process. After a fuel rod is spent, most of that U-235 has become now mostly a random collection of radioactive actinides. These may or may not be useful for any particular purpose including new fuel. This is the true waste of a nuclear reactor. 90-95% of the mass of the spent fuel is just as harmless as when it came out of the ground.

One issue with reprocessing spent fuel from a political perspective is the accumulation of recovered Pu-239, which may violate weapon proliferation treaties, etc. Pu-239 results from the bombardment of stable non radioactive U-238 with slow neutrons which starts a long chain of events that eventually stabilizes into Pu-239.


RE: No argument here.
By JonB on 3/2/2007 1:40:02 PM , Rating: 2
Uranium 238 is radioactive, but barely. It has a decay half life of 4.5 Billion Years. Uranium 235 has a decay half life of 700 Million Years. There is only one other naturally occurring isotope, Uranium 234, but its half life is so short (only thousands of years) that there isn't any in the ground.

There are scientists who have dated the formation of our planet and solar system by the decay rates of U238 and U235. When they start with the assumption that it was a even mix of the three isotopes, they first toss out the U234 since it decayed away millions of years ago. Since the natural percentage of U235 is now 0.7% to U238's 97.3%, they do the math and come up with appropriately large numbers. See the wikipedia entry. The accuracy of rock dating using this is greater than 99%.

http://en.wikipedia.org/wiki/Radiometric_dating


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