China unveils the world's first meltdown-proof thorium reactor

First meltdown-proof thorium reactor in China

Dr. Peter F. Mayer, tkp.at

Chinese scientists have reached an important milestone with a reliable and high-yield energy technology after successfully loading fresh fuel into an operating thorium molten-salt reactor, Chinese state media report.

According to Guangming Daily, the 2-megawatt experimental reactor is located in the Gobi Desert, and this latest milestone puts China at the forefront of the race to build a practical thorium reactor – long regarded as a more abundant and safer alternative to uranium. Even more significantly, China is relying heavily on long-abandoned American research in this field.

In the 1960s, American scientists built and tested molten-salt reactors, but Washington eventually abandoned the programme in favour of uranium technology.

“The USA made its research results publicly available and waited for the right successor. We were that successor” […] “Rabbits sometimes make mistakes or get lazy. Then the tortoise seizes its chance”

Project leader Xu Hongjie

The experimental reactor uses molten salt as coolant and fuel carrier, and thorium as the fuel source. For decades, thorium has been regarded as the “great reliable hope” for high-yield energy generation, as it produces less waste and more energy than uranium, cannot melt down, has no weapons-grade by-products and can even consume old plutonium stocks.

According to Xu, his team chose the more difficult but more meaningful path by developing a practical solution instead of just chasing academic results. “We chose the hardest path, but the right one,” he said. Xu and his team recreated old experiments on the basis of declassified American documents and then developed the technology further. “We mastered all the techniques described in the literature – and then went one step further,” he said.

China is already building a much larger 10-megawatt thorium reactor, which is to reach criticality by 2030. Nuclear energy is experiencing a renaissance thanks to the energy crisis triggered by the sanctions policy of the USA and its followers.

Thorium is a chemical element with the symbol Th and atomic number 90. It is a weakly radioactive, soft and ductile heavy metal and the most abundant radioactive element in the Earth’s crust. It is often extracted from monazite. On Earth it is found almost exclusively as thorium-232; other isotopes occur only in traces.

Thorium-based fuel has other important advantages. One of the biggest is that the much higher fuel utilisation reduces plutonium waste by more than 80 %. Plutonium has a shorter half-life of about 24,000 years compared with uranium-235, whose half-life is a little over 700 million years. In addition, thorium has a lower operating temperature and a higher melting point than natural uranium, making it inherently safer and more resistant to meltdowns.

Another 50 countries (mainly developing countries) have either already launched nuclear programmes or expressed interest in taking up such programmes in the near future. In total, only about 50 of the world’s 440 existing nuclear reactors can be operated with this novel fuel.

Original tkp.at article (German)

tkp.at follow-up article (13.05.2025, German)

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