Unit 4 of the Tianwan nuclear plant in China's Jiangsu province began commercial operation on 27 December after completing demonstration operation at nominal capacity for 100 hours.
Tianwan units 1-4 are VVER-1000 units built with the assistance of Russian state nuclear corporation Rosatom. Tianwan 1&2 (Phase I), two AES-91 VVER-1000 units designed by Gidropress, were built under a cooperation agreement between China and Russia. First concrete was poured for Tianwan 1 in October 1999, and the units were commissioned in June and September 2007.
Tianwan 3&4 (Phase II) are of similar design. First concrete for Tianwan 3 was poured in December 2012, and construction of unit 4 began in September 2013. Tianwan 3 achieved first criticality in September 2017 and was connected to the grid the following December, entering commercial operation on 15 February 2018. Tianwan 4 achieved first criticality on 30 September. The test run of the reactor at nominal capacity for 100 hours was completed on 22 December, China National Nuclear Corporation (CNNC) announced.
"All tests stipulated by the commissioning programme for Tianwan units 3 and 4 have been conducted," Rosatom said. "The tests have proved the nuclear island complies with the technical specifications and safety requirements set forth in the contract."
According to Alexei Bannik, ASE Group's director of projects in China, this marks the start of the two-year warranty period for the plant operation after which the unit will be handed over to China. “We can confidently state that the second stage of the Tianwan nuclear power plant has been built fully on schedule and it is evidenced by this important event," Bannik said.
China plans four futher units for the Tianwan site. The State Council gave its approval for Tianwan 5&6 (Phase III) - both featuring Chinese designed 1080 MWe ACPR1000 reactors - in December 2015. The first safety-related concrete was poured for Tianwan 5 in December 2015, and for Tianwan 6 in September 2016. CNNC plans to put both reactors into commercial operation in 2021.
In June, Russia and China signed four agreements, including for the construction of two VVER-1200 reactors at Tianwan. Contracts for Tianwan 7&8 were signed between CNNC and Rosatom in early November. Two further VVER-1200 units are to be built at China's new Xudabao site in Liaoning province.
Photo: Tianwan 4 entered commercial operation in December (Photo: Rosatom)