Nuclear reactors tend to use uranium as a fuel. This is beneficial for those who desire the plutonium byproduct of such reactors. While modern designs improve safety of nuclear power, we are left with the problem of radioisotopes to dispose of. This can be offset somewhat by using thorium as fuel. China is researching such reactors.
Imagine how the nuclear energy debate might differ if the fuel was abundant and distributed across the world; if there was no real possibility of creating weapons-grade material as part of the process; if the waste remained toxic for hundreds rather than thousands of years; and if the power stations were small and presented no risk of massive explosions.
What you’re imagining could fairly soon be reality judging from a little-noticed development in China last month.
Though apparently molten-salt reactors can run not just on thorium, but nuclear waste.
While nearly all current nuclear reactors run on uranium, the radioactive element thorium is recognized as a safer, cleaner and more abundant alternative fuel. Thorium is particularly well-suited for use in molten-salt reactors, or MSRs. Nuclear reactions take place inside a fluid core rather than solid fuel rods, and there’s no risk of meltdown.
In addition to their safety, MSRs can consume various nuclear-fuel types, including existing stocks of nuclear waste. Their byproducts are unsuitable for making weapons of any type. They can also operate as breeders, producing more fuel than they consume.
A breeder reactor is one in which isotopes present in the fuel that do not undergo fission are converted by neutron capture to isotopes that do undergo fission. Thorium reactors are breeder reactors as fissile thorium isotopes are minor so non fissile thorium must be continuously converted to uranium.
Salt reactors are also more fail-safe.
If it begins to overheat, a little plug melts and the salts drain into a pan.
And thorium is extremely abundant:
The earth’s crust holds 80 years of uranium at expected usage rates, he said. Thorium is as common as lead. America has buried tons as a by-product of rare earth metals mining. Norway has so much that Oslo is planning a post-oil era where thorium might drive the country’s next great phase of wealth. Even Britain has seams in Wales and in the granite cliffs of Cornwall. Almost all the mineral is usable as fuel, compared to 0.7pc of uranium. There is enough to power civilization for thousands of years.
So perhaps cleaner cheaper nuclear energy is on the horizon? Personally I am keen to see hydrogen fusion.