Technology Considerations for Deployment of Thorium Power Reactors

Abstract

Deployment of any nuclear reactors, in particular innovative designs, requires a healthy combination of design and safety concept maturity, design/concept validation, integration into a national energy policy, cooperation between vendor/operator/regulator bodies, and finally a sound economic/financing plan and perhaps most importantly for long-term success, supportive government policy and acceptance by an educated public. This paper briefly summarizes these aspects as they relate to unique challenges and opportunities for a potential thorium-based water-cooled power reactor program and suggests areas for technical collaboration. Based on past efforts and current knowledge, water-cooled reactors are capable of accommodating thorium-containing or even thorium-based fuel designs, known technology challenges can be mastered and there are no “showstoppers” in a gradual transition to a “complementary” thorium/uranium-based nuclear energy program, while there remain significant obstacles to full Th/²³³U implementation. The potential of thorium-based fuel options being a “better” or “superior” fuel compared to U/Pu-based fuels is clear. However, there are a few remaining areas that need further development work to generate knowledge and reduce uncertainties in existing physical parameters and implementation concepts. These are summarized and suggestions for international collaboration are made to help a gradual near-term introduction of Th fuel into the cores of current or advanced water-cooled power reactors. In light of the current lack of clear economic or overwhelming scientific advantages, perhaps the main argument for starting a thorium fuel cycle implementation is sociopolitical, namely greater public acceptance stemming from the fact that (1) Th does not carry the military connection of U/Pu and (2) the waste from any Th-based fuel cycle will have less long-lived minor actinides.