Rational restart of safer fusion energy utilization depending on the small thorium molten-salt power stations

In the next century, (a) environmental impact of CO2, SOx, NOx and CH4 from fossil fuel systems, and (b) radiowaste and nuclear proliferation (terrorism) troubles mostly coming from trans-U elements (including several thousand tons Pu) in the U-Pu solid-fuel nuclear power-stations would become severe problems in the world. To get more rational world-wide applicable power-stations as civilian utility facilities, not only the above problems (a) and (b) but also the following should be solved: (c) resource, (d) technological safety and simplicity, (e) flexibility in size and siting, and (f) integral economy in fuel cycle. A new strategy named ''THORIMS-NES'' (Thorium Molten-Salt Nuclear Energy Synergetics) is being proposed by us, which comprises of the three technologies: (I) Thorium, (II) Molten-Salt and (III) separation of power-stations and fissile breeding plants, refusing fission breeders. The typical 155 MWe Small Molten-Salt Power Station (FUJI-II) has significant characteristics as follows: (i) no needs of graphite exchange and continuous chemical processing except fission-gas removal, and (ii) fuel self-sustainability (no fissile supply) in full life after initial 500 days operation, which mean very low excess-reactivity (nearly no control-rods), few fuel transport, no core melt-down, easy operation and maintenance, few radiowaste and thermal pollution, high thermal efficiency and medium-temperature heat supply, etc. mostly achieving the targets mentioned in the above. This FUJI could be developed in this century at a small cost, smoothly joining with the present energy technologies (including the molten Na reactor technology). (author). 9 refs, 3 figs, 3 tabs