The containment water tank (CB-20 module) has been installed at the CAP1000 reactor under construction at unit 3 of China’s Haiyang NPP in Shandong province. The 419-tonne module is a major part of the reactor’s advanced passive safety system. It measures 26 metres in diameter and 10 metres in height and was lifted into place on top of the containment vessel and shielding building roof. State Power Investment Corporation (SPIC) subsidiary Shandong Nuclear Power Group said lifting the module into place took one hour and 52 minutes.
The tank will store more than 3,000 tonnes of water, which can be used to help cool the reactor in an emergency. The water can also be directed into the reactor’s used fuel pool and the tank can be refilled from water stored elsewhere on site. In conjunction with other passive safety features, the CB-20 module can maintain unit safety for 72 hours without requiring human intervention. The reactor internals were lifted into position at unit 4 in July.
The Haiyang NPP hosts two AP1000 reactors (units 1&2), which entered commercial operation in 2018 and 2019, with two CAP1000 reactors (units 3&4) – the Chinese version of the Westinghouse AP1000 – under construction.
Construction of Haiyang 4 began in April 2023 and first concrete was poured for the nuclear island of Haiyang 3 in July 2022. This marked the official start of construction of the first of two CAP1000 pressurised water reactors planned as Phase II at the site. The planned construction period is 56 months, with the two units scheduled to be fully operational in 2027.
Unit 1 of the Haiyang plant entered commercial operation in October 2018, with unit 2 following in January 2019. Together, Haiyang units 1 and 2 can provide some 20 TWh of electricity to the grid annually, sufficient to meet one-third of household demand in Shandong province.
Construction of Units 5 and 6 of the plant received official approval in April this year. “Once all the six units of the nuclear plant are fully operational, the annual power generated will be sufficient to meet the needs of 70m residents for a year. The carbon reduction achieved will be equivalent to planting 134,000 hectares of broadleaf forest, and the heating capacity will meet the clean heating needs of 25 county-level cities,” said Nan Xiaofei, a manager of the Haiyang nuclear power project with the Shandong Nuclear Power Company.
