A Thorium cycle molten salt reactor generates 0.1% of the waste of a once-through light-water uranium reactor.
The trick is that it breeds thorium to U233.
Add a neutron, and the U233 either splits, or becomes U234.
Add a neutron, and the U234 usually becomes U235.
Add a neutron, and the U235 either splits, or makes U236.
Add a neutron, and the U236 usually becomes Neptunium 237,
an unpleasant transuranic with a long half-life, but by then it's less than 1% of the starting fuel mass, and it can be finessed.
In a molten salt thorium breeder, one can just leave the Neptunium impurity in the salt, and split it and its long-lived transuranic daughters with more neutrons.
The fission waste products (things caused by splitting) all have short half-lives, most less than 30 years. So, after 300 years, the fission wastes are less radioactive than most uranium ores.
In a molten salt reactor, one can remove the fission waste products from the fuel salt (one scheme is vapor distillation from an electrically-heated graphite pan), and then return the purified fuel salts to the reactor.
The size of fission wastes are quite small. For a 1 gigawatt Thorium reactor, a year's worth of fission wastes is less than 800kg; That is, it will fit under a dinner table, and can be completely isolated from the biome. (mix it with Pyrex, put it in a copper cylinder and put the cylinder in a borehole in granite. The copper will last far more than 300 years. After that it's just strange metal ores far underground, and we already live with those.
Compare that to coal, in which a 1gW plant emits millions of kg of non-decaying hazardous fossil fuel waste directly into human biomes. Do you know, in China, coal use causes 14% of all deaths? Even in the U.S., coal use causes 1.8% of deaths. Coal kills.
Solar and wind are attractive technologies, but necessarily damage huge amounts of wildlands, compared to nuclear plants. Why would we harm the environment when there's a clearly less harmful alternative?
Molten salt thorium reactors are even -cheaper- than light water reactors, maybe even cheaper than coal plants, but that's a complicated discussion.
There's a lot more information, including U.S. government documents about successful molten salt thorium reactors, at the "Energy From Thorium" web log by Kirk Sorenson, and in the wikipedia.
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A Thorium cycle molten salt reactor generates 0.1% of the waste of a once-through light-water uranium reactor. The trick is that it breeds thorium to U233. Add a neutron, and the U233 either splits, or becomes U234. Add a neutron, and the U234 usually becomes U235. Add a neutron, and the U235 either splits, or makes U236. Add a neutron, and the U236 usually becomes Neptunium 237, an unpleasant transuranic with a long half-life, but by then it's less than 1% of the starting fuel mass, and it can be finessed. In a molten salt thorium breeder, one can just leave the Neptunium impurity in the salt, and split it and its long-lived transuranic daughters with more neutrons. The fission waste products (things caused by splitting) all have short half-lives, most less than 30 years. So, after 300 years, the fission wastes are less radioactive than most uranium ores. In a molten salt reactor, one can remove the fission waste products from the fuel salt (one scheme is vapor distillation from an electrically-heated graphite pan), and then return the purified fuel salts to the reactor. The size of fission wastes are quite small. For a 1 gigawatt Thorium reactor, a year's worth of fission wastes is less than 800kg; That is, it will fit under a dinner table, and can be completely isolated from the biome. (mix it with Pyrex, put it in a copper cylinder and put the cylinder in a borehole in granite. The copper will last far more than 300 years. After that it's just strange metal ores far underground, and we already live with those. Compare that to coal, in which a 1gW plant emits millions of kg of non-decaying hazardous fossil fuel waste directly into human biomes. Do you know, in China, coal use causes 14% of all deaths? Even in the U.S., coal use causes 1.8% of deaths. Coal kills. Solar and wind are attractive technologies, but necessarily damage huge amounts of wildlands, compared to nuclear plants. Why would we harm the environment when there's a clearly less harmful alternative? Molten salt thorium reactors are even -cheaper- than light water reactors, maybe even cheaper than coal plants, but that's a complicated discussion. There's a lot more information, including U.S. government documents about successful molten salt thorium reactors, at the "Energy From Thorium" web log by Kirk Sorenson, and in the wikipedia.