China developing thorium-powered container ship prototype

7 November 2025

China has unveiled critical details about a ‘revolutionary’ cargo ship under development—a 14,000 TEU container vessel that will be the world’s first ship powered by a nuclear, thorium-fueled reactor.

The vessel under development is powered by a 200 MW thorium molten salt reactor (TMSR) and is capable of carrying up to 14,000 standard shipping containers, making it one of the largest and most advanced nuclear-powered cargo ships ever built, according to the South China Morning Post.

The announcement highlights China’s push to apply thorium-based nuclear technology beyond land-based reactors, extending it into a mobile, compact maritime platform. The vessel’s reactor uses ²³²Th that breeds uranium ²³³U, the actual fissile material, through a neutron absorption process. Unlike traditional uranium or pressurized-water reactors, this design operates using molten fluoride salts as both fuel and coolant, allowing the system to function at low pressure but high temperature, increasing safety and thermal efficiency.

The 200 MW output of the TMSR reactor matches the power level of the S6W pressurized water reactor used in the US Navy’s most advanced Seawolf-class nuclear attack submarines.

The output of the TMSR reactor—around 200 MW of thermal energy—is converted to electricity through a supercritical CO₂ Brayton cycle, achieving thermal-to-electric conversion efficiency of about 45–50%. The system eliminates the need for vast volumes of high-pressure steam and cooling water, making it more compact and theoretically safer.

The ship’s design includes advanced shielding and containment systems, compact reactor control rooms, and redundant safety loops. It will also feature secondary diesel backup generators providing around 10 MW of auxiliary power for emergency operations and port maneuvering.

The project builds on China’s earlier success with the TMSR-LF1—a 2 MW experimental molten salt reactor completed in Gansu province in 2021. Scaling that up to a 200 MW maritime reactor involved a decade of parallel work between China National Nuclear Corporation (CNNC), Shanghai Marine Design and Research Institute, and academic partners.

If successful, the thorium-powered vessel could dramatically reduce global shipping emissions and extend the ship’s range between refueling. A thorium reactor produces no GHG emissions during operation and can run continuously for several years before refueling.

China also sees thorium as a strategic resource. The country holds some of the world’s largest thorium reserves, giving it a potential edge in developing non-uranium-based nuclear fuel cycles. Unlike uranium, thorium cannot be directly weaponized, making it more acceptable for non-military applications.

Source: thedefensenews.com