Nuclear Power from Uranium Waste

Nuclear Power from Uranium Waste: http://www.energyandcapital.com/articles/nuclear-power-from-uranium-waste/3103 'Bill Gates, of Microsoft (NASDAQ: MSFT) fame, has a storied history of philanthropy and socially conscious endeavors. Now, he is backing (and chairing) Washington-based TerraPower, a startup that aims to do no less than transform nuclear waste into nuclear fuel, generating clean electricity.
Depleted uranium is a standard by-product of conventional water-cooled nuclear reactors. TerraPower hopes to use what it calls the traveling wave reactor (TWR) to achieve this transformation of nuclear waste into energy.
As the company’s website explains, a TWR reactor can run for long periods solely on depleted uranium, or U-238. U-238 is normally produced when enriched uranium, U-235, separates from natural uranium during the nuclear power generation process.
Presently, U-235 is the fuel of choice for most light water nuclear reactors, while the U-238 generated during the process is discarded. Since conventional reactors cannot make much use of U-238—it’s too weak—TerraPower can step in to utilize this for its own energy generation, thus cutting down radically on the amount of nuclear waste.
The upshot of all this is that a TWR reactor can effectively harvest nearly 50 times more energy per pound of mined uranium compared to standard light water reactors.
The implications are obvious and vast. Such a reactor, because it works slowly and burns more efficiently, can go for 40 years without refueling (bear in mind that today’s nuclear reactors require refueling every two years or so)."