Why isn't thorium used for nuclear power?

Although in many ways thorium would be a better radioactive element to use for nuclear power, it's also more difficult to weaponise than uranium.


Asked by: Duncan Wherrett, Berwick-Upon-Tweed

Uranium and plutonium have long been at the heart of nuclear power, but many experts see thorium as a better option. It’s more abundant, comes from more politically stable sources like India and Australia, and is harder to weaponise. The reactor design is also simpler, arguably safer, and produces less radioactive waste.

Ironically, it’s the difficulty of making weapons that explains why thorium designs have yet to become commercially viable. The roots of nuclear power lie in the race to make atomic bombs, prompting many countries to adopt uranium- and plutonium-based designs.

With so much investment and expertise already committed to them, they will be around for decades yet. Even so, there is growing interest in thorium designs, especially in China, which may yet make them commercially viable.

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