Fusion–fission hybrids

The long term supplies of U-235 are inadequate, so the Pu-239 (from U-238) and U-233 (from Th-232) fuel cycles are needed. Fast breeder reactors have low breeding ratios and long fuel doubling times, so alternative technologies are desirable. A fusion reactor could provide copious neutrons to breed Pu-239 and U-233 in its blanket, supporting several (up to 15) fission reactors for increased energy production. In a liquid fuel molten salt reactor, the chemical processing equipment can remove fission products, separate bred fissile fuel, and adjust the reactivity continuously. The U-233 fuel cycle generates fewer fission products in the blanket and consumes less energy per bred fissile nucleus than the Pu-239 fuel cycle. High fuel burnup fractions (>90%) could be attained, and actinides could be recycled in the core and incinerated, instead of being considered waste requiring long term disposal. Russia is developing the Molten Salt Hybrid Tokamak (MSHT) to eliminate five vital risks: severe accidents, theft of fissile materials, actinide waste disposal, financial investment loss, and exhaustion of fuel resources.