Thorium for Safe, Clean Nuclear Power
Scientists have begun looking to thorium as a safe fuel source that produces far less nuclear waste, no weapons-grade byproducts, and at lower cost than uranium. Unlike uranium, thorium cannot start a fission explosion, making it useless as a weapon. It also degrades more quickly, and retains only 5% of the radioactivity of uranium. Spent fuel still needs to be stored safely, but for only a fraction of the time of spent uranium.
The biggest challenge to using thorium in nuclear power is that it isn't a good fuel by itself; it needs an amount of uranium or plutonium to kick-start it. Some companies have developed blends of nuclear fuel that balance thorium's beneficial properties with the other elements needed to make it work; these blends can be used to retrofit existing nuclear reactors. A Washington, DC-based company called Thorium Power has created such a blend, which is currently being used in reactors in Russia. Another technology called an Accelerator Driven System (ADS) uses an accelerator beam to energize and regulate thorium fuel rods.
Thorium may be as close as we'll come in the near future to "green" nuclear power. It's not perfect yet, but the twin crises of global warming and fossil fuel depletion will surely drive innovation and demand.
Sources: COSMOS, FuturePundit, advanced nanotechnology