Recycling of plutonium and uranium (MOX) in LWRs
Plutonium energy balance
Per metric tonne recovered plutonium the decommissioning and dismantling costs alone are estimated at more than €1bn. To provide one nuclear power plant with a first core of MOX fuel (Mixed OXide, a mixture of plutonium and uranium oxide) instead of conventionally enriched uranium, 6-7 tonnes of plutonium is required. Consequently the first core with MOX fuel will cost about as much as the construction of the nuclear power plant itself, if the decommissioning costs are accounted for.
Obviously the decommissioning and dismantling of a reprocessing plant will require investment of massive amounts of energy. By means of the energy analysis methodology these energy investment can be estimated and turns out to be about as large as the maximum energy production possible per recovered mass unit plutonium. Besides, the decommissioning and dismantling energy investments have to be added to those of the construction plus operation and maintenance of the reprocessing plant, which are also substantial.
From above observation follows that the recycling of plutonium in the current generation of nuclear reactors, by means of MOX fuel, has a negative energy balance. That means that plutonium recycling would consume more energy than it adds to the net energy production. A large part of the necessary energy investments are passed on to the future generations: an energy debt [more i16].
Plutonium recycling unavoidably generates uncontrollable risks of nuclear terrorism and proliferation. Using elementary chemistry MOX fuel can be separated into uranium and plutonium. The plutonium could be used to produce a crude nuclear weapon. Evidently such a weapon wouldnÕt have the reliability and yield of a military weapon, but even a nuclear explosion of a few kilotons in the center of a town could be devastating. Even without a nuclear explosion the dispersion of several kilograms of plutonium over a town by a small plane may render the town inhabitable.
Reprocessed uranium can only be used in MOX fuel, because its fissile content is too low to sustain a fission process in a reactor. Enrichment of reprocessed uranium to appropiate levels by means of diffusion or ultracentrifuge is not feasible, due to its high radioactivity and unfavourable isotopic composition. Reprocessed uranium contains uranium-234 and uranium-236 isotopes, which are highly radioactive and non-fissile. Enrichment of reprocessed uranium means also enrichment in U-234 and U-236. As a consequence the fissile component of nuclear fuel has to be plutonium. Fuel fabrication from reprocessed uranium has to be done by remotely controlled equipment, due to the high radioactivity of the material.
For reasons explained above the reuse of reprocessed uranium in nuclear fuel will result in a negative energy balance of nuclear power.
View of the nuclear industry
The optimistic view of the nuclear industry with respect to the recycling of plutonium seems to be based just on short-term economic arguments.
Apparently the nuclear industry is convinced that regulations conceived on paper offer watertight guarantees against terrorism with MOX fuel.
The view of the nuclear industry lets no room for decommissioning and dismantling of reprocessing plants and the energy balance of plutonium recycling appears to be a non-item. The energy investments and financial costs of the plutonium recovery are not accounted for and not balanced with other investments.