Outer dome installed on Chinese small modular nuclear reactor

Wednesday, 7 February 2024

The reactor building for the ACP100 - also referred to as the Linglong One - consists of three parts: the internal structure, the steel containment shell and the outer concrete shielding shell. The inner steel containment dome was installed in November.

The operation to lift and place in position the outer shell, which weighs about 550 tonnes, took one hour and thirty eight minutes on 6 February, in time for Chinese New Year and the Spring Festival holidays. CNNC said that 6000 workers at the Linglong One project site will stay at their jobs "and go all out to ensure that the project is completed on time".

Chen Weimin, deputy director of the Hainan Nuclear Power Engineering Management Office, said: "The hoisting of the outer dome into place means the main structure of the reactor building has been completed and laid the foundation for the subsequent capping of the reactor building." He said that there had been valuable experience for subsequent modular development of new nuclear.

The weather conditions had to be suitable for the operation (Image: CNNC)

CNNC announced in July 2019 the launch of a project to construct an ACP100 reactor at Changjiang in Hainan Province. The site is already home to two operating CNP600 PWRs, while the construction of the two Hualong One units began in March and December 2021. Both those units are due to enter commercial operation by the end of 2026.

First concrete for the ACP100 was poured on 13 July 2021, with a planned total construction period of 58 months. Equipment installation work commenced in December 2022 and the main internal structure of the reactor building was completed in March 2023.

Under development since 2010, the 125 MWe ACP100 integrated pressurised water reactor's (PWR's) preliminary design was completed in 2014. In 2016, the design became the first SMR to pass a safety review by the International Atomic Energy Agency.

Once completed, the Changjiang ACP100 reactor - which CNNC describes as "the world's first commercial land-based small modular PWR" - will be capable of producing 1 billion kilowatt-hours of electricity annually, enough to meet the needs of 526,000 households. The reactor is designed for electricity production, heating, steam production or seawater desalination.

The project at Changjiang involves a joint venture of three main companies: CNNC subsidiary China National Nuclear Power as owner and operator; the Nuclear Power Institute of China as the reactor designer; and China Nuclear Power Engineering Group being responsible for plant construction. For the demonstration plant, the reactor vessel is being supplied by Shanghai Boiler Works Limited, the steam generators by a CNNC subsidiary and other reactor internals by Dongfang Electric Corporation.