Researchers at the Chinese Academy of Sciences have successfully reloaded a thorium-powered nuclear reactor while it was powered up, marking a world first for on-line refueling. The two-megawatt research unit, located in the Gobi Desert, had achieved full-power operation last June, according to the South China Morning Post.
The milestone was revealed during a private meeting earlier this month. The reactor uses molten salt as both fuel carrier and coolant, a design that theoretically carries far less risk in the event of a meltdown compared to water-based systems. Because the fuel is already molten, a traditional meltdown is essentially a non-factor. A U.S. government-sponsored report on molten salt reactors notes that upon breach of a vessel or pipe, the fuel would disperse, increasing its cooling geometry until it freezes and becomes confined to that location—unlike the steam explosion at Chernobyl.
Thorium offers a more accessible but less weaponizable alternative to uranium, according to the World Nuclear Association, which states that thorium-based fuels would be a poor source for fissile material usable in illicit explosive devices. Molten salt reactors are not new; the U.S. invested nearly $1 billion in thorium-fueled aircraft research in the late 1940s and early 50s, but Congress halted the program in 1961, and uranium became dominant due to its military potential.
The Gobi Desert team's work builds on public U.S. research. "The US left its research publicly available, waiting for the right successor," said chief scientist Xu Hongjie. "Rabbits sometimes make mistakes or grow lazy. That's when the tortoise seizes its chance."
Editorial Notes