Two Russia-supplied reactors under construction at site

The lower half of the inner steel liner for the containment dome has been lifted into place at Tianwan-7. Courtesy Rosatom.

The lower half of the inner steel liner for the containment dome has been lifted into place for Unit 7 at the Tianwan nuclear power station under construction in Jiangsu province, eastern China.

The dome is part of the reactor building’s physical protection system, which is designed to withstand high external and internal pressures and protect against radiation release.

Russian state nuclear corporation Rosatom, supplier for the Tianwan-7 project, said the 390-tonne component was placed on top of the previously installed inner containment building steel dome, part of the inner hermetic protection system.

Rosatom said VVER-1200 pressurised water reactor (PWR) systems have a two-part containment by design – one to protect from external physical influence and a second to secure the hermetic tightness around the core reactor equipment.

The Tianwan nuclear station has six PWR units in commercial operation and two under construction.

Tianwan-7 and -8 will both be Russia-made VVER-1200 Generation III+ PWR units under agreements signed in 2018 and 2019.

Russia already supplied its VVER-1000 technology for the commercial Tianwan-1, -2, -3, and -4, while Units 5 and 6 operate the domestic CNP-1000 PWR design.

Construction of Tianwan-7 began in May 2021 and Tianwan-8 in February 2022.