On potential of thermo-nuclear fusion as a candidate for external neutron source in hybrid systems (applied to the “WISE” concept)

The WISE (Waste-free, Intrinsically Safe, and Efficient) concept, based on the sequent application first natural U and then Th liquid fuel (molten salt, liquid metals, etc.), seems to be particularly attractive for Nuclear Power (NP) both for transmutation of wastes and for long-term energy production. However, the use of natural thorium fuel as well as of “once-through fuel cycle” make neutronics of WISE-core particularly weak and it requires a significant external neutron source to support sub-critical cores. Traditionally, spallation reactions have been considered as a potential source in Accelerator Driven Systems (ADS), although an important fraction of elaborated power must be spent to feed the corresponding powerful accelerators. Fusion types of the external neutron source, if they are relatively small and economically viable, can allow to get more advantages of WISE concept. The general analysis, given in this paper, shows that a fusion source is a real alternative to a spallation type of neutron source for multiple hybrid applications.