I have blogged about thorium as a nuclear fuel before.
Thorium is being pushed by some in the nuclear industry as a better nuclear fuel alternative that uranium. Here are ten reasons that this may not necessarily be true.
1) There is no such thing as an operational thorium reactor for power generation. A number of reactor designs have been researched and some test reactors have been built. Before thorium could be used for a fuel, a reliable and safe thorium reactor must be built and tested which might take decades before any possible commercialization.
2) Thorium reactors require uranium or plutonium to provide neutrons because thorium by itself is not fissile and cannot sustain a chain reaction.
3) A thorium fuel cycle utilizing plutonium would add to the risk of nuclear weapons proliferation because plutonium would need to be purified to weapons grade in order to be used in a thorium reactor.
4) Thorium in a reactor is converted to uranium-233 which is already enriched to weapons grade in the reactor. This adds to the danger of nuclear weapons proliferation.
5) Mixing thorium with uranium 238 will not cancel the risk of nuclear weapons proliferation. U-238 in a thorium reactor would be converted to plutonium -239 which can be used for weapons.
6) Thorium reactors would cause the U.S. to start reprocessing nuclear fuel again. Most thorium fuel cycles require extraction of U-233 from spent fuel in order to mix it with thorium for new fuel. Reprocessing generates radioactive waste that must be dealt with.
7) Using thorium for nuclear fuel does not eliminate the problem of long term highly radioactive waste. Thorium 232 which is generated in a thorium reactor has a half life of fourteen billion years and its decay products build up in irradiated fuel. The irradiated fuel itself is also very toxic. Thorium mining also generates dangerous waste products just like uranium mining.
8) Attempts to develop a useable thorium reactor have failed. India, Russia and the United States have spent decades and billions on developing such a reactor without success.
9) The creation of thorium fuel would pose a threat to public health. U-233 is created which is very radioactive and dangerous. Thorium 232 is part of the cycle and Inhaling a particle of thorium 232 results in much greater radiation exposure than inhaling a similar amount of uranium.
10) Creating thorium fuel will be expensive. Thorium fuel required both the reprocessing of spent nuclear fuel and the irradiation of rods of thorium. A thorium fuel cycle would cost much more than the current uranium fuel cycle.
So thorium reactors would be difficult to build, would be expensive to fuel and would produce long lived dangerous waste. Other than the billions made by the builders and operators of thorium reactors, there would be little benefit to anyone in converting to thorium reactors for energy production.
