Advanced plutonium management in PWR, complementarity of thorium and uranium

• We model 7 different steady-state electro-nuclear scenarios.
• We make a comparison between these scenarios at different points of the fuel-cycle.
• Low breeding capacity of thorium-fuel in PWR leads to no significant gain.
• Pu-recycling in homogeneous assemblies leads to high Pu inventory, even using Th.

The possible delay of decades for the deployment of fourth generation reactors brings up new issues. First, the possibility of higher tension on uranium mining motivates the research of a better use of resources in PWR. Second, countries like France which are storing spent MOX fuels containing plutonium in prediction of starting FBR could have to adapt their plutonium management strategy.Different options and different types of uranium and thorium based fuels in PWR have been studied using the MURE core. The steady-state of all considered strategies is calculated taking into account the whole nuclear cycle, allowing a precise description of the fuel composition and behavior at each step.The study is made in the most similar strategy of fuel reprocessing and allows a real comparison of U and Th cycles. It shows the low breeding capacity of thorium-fuel in PWR that leads to no significant gain on resource consumption. Moreover multireprocessing plutonium on thorium matrix implies to reprocess it in dedicated ThPu assemblies in order to be able to recover 233U. This leads to high plutonium concentrations. The global comparison, that takes into account the whole fleet, between plutonium recycling on depleted uranium or thorium based fuel is then not such favorable for thorium in terms of total plutonium inventories in the fleet at steady state. The same effect is observed for americium production.