China installs outer dome on Lianjiang unit 1, marking major milestone

A 1,000-tonne outer dome now sits atop Lianjiang unit 1 in Guangdong province, turning one of China’s newest CAP1000 projects from a visible civil-engineering job into a tighter race to install the hardware inside. The module, built with 32 radial main beams, three ring beams, 96 steel cladding panels and three steel platforms, caps the double-layered containment building and the steel-concrete composite structure that supports the passive containment cooling water storage tank.

China National Nuclear Corporation said the lift marked completion of the main structure for unit 1, a milestone that matters far beyond the photo-op. With the dome in place, the plant can move deeper into equipment installation and containment completion, the point where a nuclear project stops looking like a concrete skeleton and starts looking like a reactor building. For Lianjiang, that shift is especially important because phase I covers two 1,250 MWe reactors and the full site is planned for six CAP1000 units.

The schedule behind that dome shows how hard the project has been pushed. The first two reactors were approved by the State Council of China in September 2022, and excavation began that same month. First safety-related concrete for unit 1 followed in October 2023, with unit 2’s first safety-related concrete poured on April 26, 2024. On unit 1, the containment vessel bottom head was installed on December 19, 2023, the CA01 super module went in during April 2024, the reactor pressure vessel arrived on February 18, 2025 and was installed on February 28, 2025, and the second steam generator was installed on October 29, 2025. The auxiliary building topped out on August 20, 2025.

The cooling side has been advancing in parallel. SPIC says Lianjiang is the first nuclear power project in China to use seawater secondary circulation cooling and a super-large cooling tower. At the site, the tower foundation was laid in November 2023 and the tower’s main structure was completed on September 19, 2025, underscoring how unusual this coastal build is.

That sequence of dome lift, vessel placement, steam-generator installation and auxiliary-building completion is exactly the kind of construction rhythm that nuclear watchers use to judge whether a project’s dates are real. Unit 1 is expected to enter operation in 2028, and when all six reactors are finished, CNNC and SPIC project annual generation of about 70.2 TWh, enough to displace more than 20 million tonnes of standard coal. For Lianjiang, the dome is not just the top of the building. It is the point where the schedule has to keep proving itself in steel, concrete and heavy equipment.