Unit 1 at China’s Sanmen NPP in Zhejiang province achieved first criticality on 21 June, according to China’s State Nuclear Power Technology Corp (SNPTC). The plant will be the first in the world to be based Westinghouse Electric’s AP1000 reactor design when it begins operation later this year. Westinghouse currently has six AP1000 nuclear power plants progressing through construction, testing and start-up – two units each at Sanmen, Haiyang NPP in China’s Shandong Province, and two units under construction at the Alvin W Vogtle NPP in Georgia, USA. Westinghouse, SNPTC and Shangdong Nuclear Power Co said that unit 1 at Haiyang began to load 157 fuel assemblies on 22 June after completing the necessary testing and regulatory reviews conducted by China’s National Nuclear Safety Administration (NNSA). Haiyang 1 is also expected to begin operation before the end of 2018.

In September 2007, Westinghouse and its partner the Shaw Group won approval to construct four AP1000 units in China: two each at Sanmen and Haiyang. Construction of Sanmen 1 began in April 2009, while first concrete for Sanmen 2 was poured in December 2009. Construction of Haiyang 1 and 2 began in September 2009 and June 2010.

"The lessons learned and resources shared between Sanmen and Haiyang throughout all phases of construction and start-up have made tremendous improvements in terms of quality and execution, which will benefit future AP1000 fleets," said Gavin Liu, Westinghouse's president for the Asia Region. "We will continue to work side by side with our Chinese customers and ensure the success of the remaining testing."

However, progress has not been without its problems. Sanmen 1 was originally planned to startup in 2013, but design problems, supply chain bottlenecks and the need for additional safety measures caused delays. Westinghouse was purchased by Canada’s Brookfield Business Partners after it filed for bankruptcy in 2017 due to delays and cost overruns at four AP1000 units under construction in the USA. Two of these, at the VC Summer NPP, been cancelled.

China had previously also signed a contract with Westinghouse to build two AP1000 units at Xudabao, according to a World Nuclear Association report in October 2016. They were among six AP1000 reactors planned for the site. However, these plans appear to have been dropped. On 8 June China signed an agreement with Russian state nuclear corporation Rosatom for the construction of two Generation 3+ VVER-1200 reactors at Xudabao.