Recently it was reported in Defense Daily that the White House Office of Management and Budget has moved to remove all research in fast-spectrum fission reactors from the DOE budget. This in turn prompted an outcry from the Secretary of Energy, Stephen Chu, who stated:
“Prohibiting research and development on fast reactors under the fuel cycle research and development budget line effectively selects the once-through fuel cycle as the only fuel cycle to be pursued in the United States”
With all due respect to the Secretary, there is another option. This is precisely the fork in the road that visionaries like Wigner and Fermi saw back in the late 1940s. If you pursue closed-fuel cycles based on uranium (and predominantly uranium-238) then Chu is right–the fast spectrum reactor is the only option for a closed-fuel cycle, since only in the fast spectrum can U-238 be productively consumed.
But…if you consider thorium as the basic fuel, as Wigner advocated, then you can have a closed fuel cycle WITHOUT a fast spectrum reactor, since thorium can be productively converted to energy in a “slow” neutron reactor (called a thermal-spectrum reactor) and thorium is the only option for this approach.
If the White House wants a transformational nuclear technology, that is not a fast reactor, closes the fuel cycle, increased safety and efficiency, opens the doors to hydrogen and chemical fuel production, is capable of using its waste heat for desalination, and is highly proliferation-resistant, then may I respectfully submit:
The Liquid-Fluoride Thorium Reactor!