Nuclear energy for the future: CEA strategic R and D orientations

Worldwide energy consumption is expected to double over the next 50 years. If there is no major change in the trend, this growth should quickly cause depletion of fossil fuel resources, a dramatic increase in the contents of greenhouse effect gases and a serious supply risk for many countries. Beyond energy savings and the development of renewable energies, nuclear energy can provide a sustainable solution to these increased needs. This is the context in which the CEA is developing its nuclear R and D strategy for the future. One objective is to optimize and develop the current nuclear facilities : R and D for nuclear energy should increase the competitiveness of existing nuclear facilities, further improve safety. Water reactors (PWR and BWR), based on design principles that are now almost 40 years old, have been improved over time, but also made more complex due to increasing safety requirements, and more powerful through economic optimization. Enriched uranium fuels are safe and reliable. Pressurized water reactors are expected to become even more competitive in time with the new reactor designs (EPR) and the life extension of existing power stations. Nuclear energy sustainable development will only succeed with public acceptance. Solutions to Plutonium inventory management (see paper nr. 665) must be provided by either using it in fast neutron reactor where it as the most energy production efficiency or burning it out in existing - or future - PWR. Another objective is to bring efficient and acceptable solutions for HLLL waste management (see paper nr. 666) and reinforce knowledge on health and environment impact of nuclear activities. The third objective is to prepare and assess new generations of nuclear energy systems. Water reactors only consume 1% of the initial natural uranium and irradiated fuels still contain 96% of energetic material ; they also have a limited turbine efficiency. Industrial fast neutron reactors have been built. These reactors have intrinsic advantages ; they are capable of making use of the entire energy potential in the uranium and produce less waste. However, sodium, as a coolant, has some drawbacks related to its chemical reactivity, and make more complex the inspections. Beyond these technologies, high temperature gas-cooled reactors are promising. They are simple and could be standardized, hence be economic. They could have good passive safety characteristics mainly thanks to the fuel properties (refractor, conductor, and confining) , they could accommodate fast spectrum cores with the advantage of an inert coolant. Therefore, CEA is dedicating its main efforts towards the development of the Gas Cooled Reactors (see paper nr 667) (GCR) technological range (materials, fuel, helium cycle and technology) with the objective of defining and producing a first flexible test reactor by 2012 and, shortly afterwards, combined with an integrated cycle experiment. The field of future nuclear energy systems studies is a most appropriate subject of collaboration between European countries, and with the USA, Japan and Russia. Therefore the CEA resolutely decided to integrate its R and D effort in European networks and Framework Programs. Therefore also, it decided with industrial partners to be an active member of the Generation IV International Forum launched in 2000 by the US-DOE with a view to organize a road mapping activity of promising technologies for future nuclear energy systems. France acts also as an attentive observer in the IAEA INPRO program. (author)