Model calculations of prompt fission neutron spectra of ²³²Th(n,f)

With increasing awareness of the global changes of the environment, nuclear power is regaining its position as the most appropriate option to produce great quantities of energy with negligible emission of greenhouse gases. This position is subject to the conditions of increased safety, reduction of the risk of fissile material proliferation and a viable solution to the problem of long-term radioactive waste disposal. In this context new concepts of nuclear technology for power production are being investigated, the thorium-based nuclear fuel cycle being an appropriate option because of advantages such as: i) the fissile nucleus ²³³U of this fuel cycle is a very efficient nuclear fuel (a reactor concept based on Th-U fuel being feasible); ii) the world reserves of Th are much larger than the reserves of uranium; iii) the production of long-live actinides, which are the main source of long-term residual radioactivity of the nuclear waste, is much smaller in the Th-U fuel. This fact can be used with advantage in the design of critical as well as sub-critical accelerator-driven systems (ADS); iv) the Th-U fuel is more proliferation-resistant due to the highly radioactive constituents which cannot be separated out by chemical means. Handling of such materials in improvised clandestine laboratories is practically impossible.