Unit 5 of China’s Tianwan NPP in Jiangsu province has been connected to the grid for the first time, China National Nuclear Corporation (CNNC) announced on 10 August. The 1080 MWe domestically-designed ACPR1000 pressurised water reactor, which achieved first criticality on 27 July, will now undergo tests at 30%, 50% and 100% of its generating capacity before entering a full power demonstration operating assessment. During this assessment stage, the performance indicators of the unit will need to meet design standards and the relevant requirements of the power grid, which will indicate that the unit has achieved formal commercial operating conditions, CNNC said.

Plant operator Jiangsu Nuclear Power Corporation is a joint venture between CNNC (50%), China Power Investment Corporation (30%) and Jiangsu Guoxin Group (20%). Tianwan 5&6 are both ACPR1000 reactors. First concrete was poured for unit 5 in December 2015 and for unit 6 in September 2016. Bothe units are scheduled to begin commercial operation by the end of 2021. China's National Nuclear Safety Administration issued a 40-year operating licence for Tianwan 5 earlier in and fuel loading followed. Tianwan 5 is seen as a Generation II+ design and a precursor to Generation III designs. Tianwan 1-4 are Russian supplied VVER-1000 units. Tianwan 1&2 were put into warranty operation in 2007, and Tianwan 3&4 began commercial operation in 2018. Tianwan 7&8 will be equipped with Generation 3+ VVER-1200 reactors. Construction of unit 7 is expected to begin in 2020.