[en] This report first proposes an analysis of the past expenses in the electronuclear sector (physical investments, research expenses from 1945 to 2010, the case of Superphenix), of the current expenses (operation costs for EDF, other types expenses), of the future expenses (dismantling of nuclear installations, management of used fuels, management of radioactive wastes), of expense provisions and actualization, of dedicated assets (regulatory and legal framework, application modalities of asset management for EDF, AREVA and the CEA), of the possible evolutions of future expenses (effect of reactor operation lifetime, future researches, EPR costs, scenarios), of costs which are difficult to precisely assess (externalities, nuclear risk and insurance)