From pressurized water reactors to sodium fast reactors : A multicriteria roadmap for closing France’s nuclear fuel cycle

This thesis explores the feasibility and implications of transitioning France’s nuclear system from pressurized water reactors (PWRs) toward generation IV sodium-cooled fast reactors (SFRs) to achieve a closed nuclear fuel cycle: the absence of need for natural uranium to fuel the nuclear reactors. Four chosen scenarios, from an open fuel cycle to a fully closed SFR fleet, are modeled with a multi-criteria framework to evaluate strategic, economic, industrial and sociopolitical challenges. The framework constructed suggests that while SFRs are still economically uncompetitive under current economic conditions, their strategic value in reducing dependency on natural uranium and industrial deployment span justifies their current consideration. The study concludes that transitioning from current PWRs to SFRs should be analyzed not solely as a short-term economic optimization, but as a long-term national strategy requiring political stability and industrial readiness.