Thorium as a nuclear fuel: myths and realities

This study is intended to provide a ‘fresh look’ of the thorium nuclear fuel cycle which is considered by some experts as a complement or even a substitute of the classical uranium nuclear fuel cycle for the operation of nuclear reactors. The authors first examine the incentives that led to numerous studies in the past and that still justify the continuation of some work on this topic in the world. For that purpose, they describe and explain the main physical and nuclear properties of thorium as well as those of the fissile isotope that is generated by the thorium, uranium-233, since this is its major advantage. They also give a summary of the available data on terrestrial thorium reserves. Then, they present an overview of the history of the development of thorium cycle including the acquired experience of its use in nuclear reactors. On these bases, they explain the various problems that may arise using the thorium cycle on an industrial scale, from the front end of the fuel cycle to the final stage of spent fuel reprocessing and recycling of materials and vis-à-vis the waste associated with this cycle. Finally, they discuss some generic issues related to implementation of the thorium cycle, in particular the issues of non-proliferation and economy. A conclusion is a summary of the advantages and disadvantages of thorium cycle and its development prospect.