THE MYTHOLOGY AND MESSY REALITY OF NUCLEAR FUEL REPROCESSING
Arjun Makhijani, Ph.D. April 8, 2010
On the Web at http://www.ieer.org/reports/reprocessing2010.pdf
G. Reprocessing and spent fuel stocks from existing U.S. reactors
As we have seen, statements that 90 or 95 percent of the material in spent fuel can be used are completely invalid without breeder reactors. In this section we will examine some of the implications of a policy that seeks to deal with existing spent fuel by trying to convert the mass of the material into fuel and using it for energy, assuming that breeder reactors will work and can be deployed on a large scale.
We start with a heuristic calculation. A 1,000-megawatt nuclear power reactor fissions about one metric ton of heavy metal per year in the course of energy generation. At present, there are over 60,000 metric tons of spent fuel in the United States. With reactor re-licensing, the total amount of spent fuel could amount to well over 100,000 metric tons by the time the reactors are retired; 95-plus percent of the content of this spent fuel is uranium or transuranic elements (mainly plutonium). We will use a round number of 100,000 metric tons92 of uranium and plutonium content in spent fuel that would be converted into fuel. This corresponds approximately to statements that 90 or 95 percent of existing spent fuel has “energy value” and hence should not be regarded as waste. For instance, such a scheme would appear to be the one that Dr. Miller had in mind and that NRC Commissioner Bill Magwood made explicit in his discussions of spent fuel management.93
Setting aside for the moment a variety of difficult issues, including those associated with the rate of conversion of uranium-238 into plutonium, it is easy to see that it would take 100,000 reactor years (assuming 1,000 megawatt reactors) to convert the heavy metal content of spent fuel from the existing fleet of U.S. power reactors into fission products in a manner that extracts essentially all the physically possible energy value in it.
Assume a reactor operating life of 50 years, accumulating 100,000 reactor years would mean building 2,000 reactors to extract the energy in the total spent fuel from the existing fleet of reactors. This is about 20 times the size of the existing U.S. nuclear power system. It is four times the total electricity generation of the United States and seven or eight times the baseload requirements under the present centralized electricity dispatch system. If the material is consumed in a smaller number of reactors, the time to consume it would be proportionally increased. For instance, it would take 200 years to consume the material in 500 reactors.
The matter gets more complex when
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