Thorium (Th-232) is among the least radioactive materials (half life 14 billion years); you can safely hold in your hand enough to generate all the electricity you’ll use in your entire life.
Thorium can’t fission (is fertile, not fissile), must be converted into Uranium before it can produce energy. This happens inside the reactor (no fuel fabrication):
- Uranium in the reactor core releases neutrons,
- Thorium in a salt “blanket” around the core absorbs a neutron, and decays in a few steps into U-233, which is fissile.
- Bubbling fluorine gas through the blanket salt converts Uranium (as UF4) to a gas (UF6), which is collected and converted back to UF4, then transferred into the fuel salt.
The Department of Energy is planning to destroy all our existing U-233, at a cost of $500 Million. This will be needed to start fission in the first molten salt reactors. “We are currently not supporting any projects that require U233 for testing. As such, the disposal of U233 will go forward.” – DoE. Molten Salt Reactors are one of the reactors proposed for the Generation IV International Forum, that the United States is part of, for example see DoE’s A Technology Roadmap for Generation IV Nuclear Energy Systems (2002). Sign the online petition to stop the destruction of U-233, http://wh.gov/EgnF.