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Chinese Thorium & China's Tech Boom

China Discovers 60,000-Year Supply of Thorium – How Big is this News?

Image: Thorium. Credits: Rui Costa via Flickr

A geological survey in China has found thorium supplies that could power the country for 60,000 years. This big news circulated through the media last week. How important is this finding? Let’s have a look.

The news came from the South China Morning Post and from there spread rapidly all over the world. The Morning Post claims to have seen a declassified report of a survey from 2020, according to which the Bayan Obo mining complex in the Inner Mongolia region of China could yield 1 million tonnes of thorium from mining waste.

This would mean that China has the world’s largest thorium reserves, and would put it on top of the list, ahead of India, Australia, Brazil, and the United States.

If thorium ever becomes an important natural resource, this would give a lot of economic power to China. And it could become an important resource, because thorium can be used for nuclear fission, basically making this a vast supply of carbon-dioxide free energy.

Using thorium for nuclear reactors has several advantages over the currently most commonly used uranium. One is that there’s about 3 to 4 times more thorium in the Earth’s crust. It also can’t be as readily used for nuclear weapons, though if you make some effort that’s still possible.

The real advantage of thorium reactors is that they can use essentially the entire fuel, not just a small fraction of it, as is the case with the uranium reactors. This means that the energy you can extract from a certain mass of thorium is much higher than for the same mass of uranium.

Thorium itself is not fissile which means you can’t run a chain reaction with thorium alone. You need to start the reaction with some other element, typically one uses uranium. However, that requires far less enriched uranium. This too is a big advantage because enriched uranium has become really expensive and the main supplier is Russia.

For this reason, thorium reactors have attracted a lot of interest recently. China has already been running a small thorium reactor for a few years. This has been a test project with merely 2 megawatts of power. I assume things went as planned, because this year they want to start building a bigger demonstration reactor with 10 megawatts in power — it’s supposed to be operational by 2030.

And after that, I guess they will go to small modular reactors of 100 megawatts or so.

These thorium reactors are molten salt reactors, a type of design that powers itself down automatically in case the cooling system fails.

This all sounds great. So could you power China from thorium from 60,000 years? Probably, yes. But how revolutionary is this finding really? It's hard to say precisely because unfortunately I have not been able to find the report that the Morning Post writes about.