Remarks on the thorium cycle

Abstract

The use of thorium and neutrons to make U-233 would provide energy for many thousands of years. Thorium is more abundant than uranium and U-233 is the best fissile material for thermal neutron reactors. Four approaches to the use of thorium are worth developing: heavy water moderated reactors with conversion ratios greater than 0.9, such as modified CANDU with lower cost of separating D 2O and U-235; molten salt breeder reactors, from which fission products and excess fuel may be continuously removed; fusionfission hybrids that produce adequate tritium and excess neutrons for sustenance and U-233 production in a subcritical thorium U-233 blanket; and by fission-initiated-thermo nuclear explosions in cavities in salt beds one mile below the earth's surface yielding U-233 from the excess neutrons and thorium and decontaminated steam for power production.