The outer dome of the double containment has been installed at unit 1 of China’s Lianjiang NPP in Guangdong province, China, China National Nuclear Corporation (CNNC) reported. CNNC is building the station on behalf of the State Power Investment Corporation (SPIC) The NPP is planned to have six CAP1000 reactors – the Chinese version of the Westinghouse AP1000.
Construction of the first two 1,250 MW CAP1000 reactors – the Chinese adaptation of the Westinghouse AP1000 reactor – at the Lianjiang site was approved by the State Council (Government) of China in September 2022. Excavation work for the units began the same month. First concrete for unit 1 was poured in September 2023, and for unit 2 in April 2025. The reactor vessel for unit 1 was installed in February 2025 with operation planned for 2028.
When all six units of CAP1000 are completed, annual electricity generation will be about 70.2 TWh, reducing standard coal consumption by more than 20m tonnes and reducing carbon dioxide emissions by more than 52m tonnes, sulphur dioxide by about 171,000 tonnes and nitrogen oxides by about 149,000 tonnes.
The steel dome, with a lifting weight of almost 1,000 tonnes, has a conical shape, consisting of 32 radial main beams, three annular beams, 96 steel cladding panels and three steel platforms connected at the bottom. Its diameter is about 41 metres and its height 11 metres. It is an essential component of the containment, located on top of a steel-concrete composite structure and supporting a passive water storage tank to cool the pressure shell.
The CAP1000 reactor design uses modular construction methods to produce large structural modules in factories and then install them on site. This means more construction work can be done in parallel, reducing construction time as well as providing economic and quality control advantages.
“This marks the official completion of the main structure of unit 1’s reactor building, signifying the project’s transition from the civil engineering phase to the equipment installation phase, laying a solid foundation for the subsequent work,” CNNC said. “As a critical final stage in the modular construction of the steel structure, the dome is not only a key symbol of the structural closure of the main building, but also a critical barrier to ensure the safe and stable operation of the nuclear power plant.”
SPIC said the Lianjiang NPP will be the first nuclear project in China to use secondary seawater circulation technology for cooling, as well as the first to use a super-large cooling tower.
