China boasts world's largest nuclear power capacity with manageable risks: official

China

China boasts world's largest nuclear power capacity with manageable risks: official

2025-04-26 11:42 Last Updated At：12:37

China has emerged as the world's largest nuclear power operator in terms of installed capacity, with tight regulations for radioactive waste disposal, the Ministry of Ecology and Environment said on Wednesday.

Up to now, the installed capacity of nuclear power units on the Chinese mainland has reached 113 million kilowatts, ranking first globally, the ministry told a regular press conference in Beijing.

While China's nuclear power industry began relatively late, the country has effectively absorbed international experiences and adopted advanced, reliable reactor designs, allowing it to gain a competitive edge in the sector.

To date, nuclear power units on the Chinese mainland have safely operated for over 600 reactor-years with an excellent safety performance.

"Nuclear facilities inevitably generate radioactive wastes during their normal operations, which are categorized into gaseous, liquid, and solid forms. Both gaseous and liquid wastes are treated to meet national standards before being released into the environment. Meanwhile, solid waste is classified and handled according to its radiation levels. Currently, over 90 percent of solid waste generated by China's nuclear power plants during normal operations is low-level radioactive waste," said Liu Lu, director of the Radiation Source Safety Regulation Department under the Ministry of Ecology and Environment.

Under strict supervision, each million-kilowatt nuclear power unit produces no more than 50 cubic meters of low-level radioactive solid waste per year. After temporary on-site storage, this waste is transported to centralized disposal facilities for permanent containment. High-level radioactive materials generated during nuclear plant operations are also subject to extremely strict safety requirements, with full-process supervision from production to disposal.

According to the ministry, China has also established the world's largest radiation monitoring network over the years, ensuring that radiation levels around nuclear facilities remain well within safe limits.

The national network includes 1,835 monitoring points, covering all cities at or above the prefecture level, key border ports, and areas surrounding nuclear facilities.

Additional provincial networks further expand the monitoring coverage. In total, more than 100 monitoring points have been established around key nuclear plants, including automatic atmospheric radiation monitoring stations and environmental sampling points for water, soil, and wildlife.

Monitoring data confirms that the country's radiation environment has remained at safe levels for many years.

Chinese optical clock accurate to within 1 second over 30 bln years

Researchers from the University of Science and Technology of China have achieved a major breakthrough in optical clock technology, developing a strontium optical lattice clock with stability and uncertainty both surpassing the 10⁻¹⁹ level, meaning the clock would lose or gain less than one second over roughly 30 billion years.

The findings were published in the international metrology journal Metrologia on Thursday.

Optical clocks are considered the most precise timekeeping devices currently available. They measure time by using the frequency of light emitted when electrons transition between energy levels in atoms. They can directly support the redefinition of the second in the International System of Units.

"This breakthrough enables China to rank among the top in the world in the development of optical clocks. It also provides a feasible technical path for the development of transportable optical clocks and satellite-borne optical clocks, and lays a solid and reliable foundation for using optical clock technology in areas such as testing fundamental laws of physics, supporting next-generation satellite navigation systems, and establishing a globally unified ultra-high-precision time reference," said Dai Hanning, professor of the university.

Beyond time-keeping, optical clocks can provide highly accurate time references for modern technologies such as satellite navigation, telecommunications and precision measurements. They also offer new experimental platforms for testing fundamental physics, including general relativity, as well as for the detection of gravitational waves and dark matter.

Achieving both stability and uncertainty at the 10⁻¹⁹ level opens the door to a range of frontier applications. These include millimeter-level measurements of gravitational potential and altitude, which could help monitor crustal deformation, groundwater changes and volcanic activity, as well as improve geoid mapping for disaster prevention and resource exploration.