Milestones in the commissioning of the AP1000s under construction at the Haiyang nuclear power plant in China's Shandong province were met on 8 August. Unit 1 achieved first criticality, while fuel loading started at unit 2.

Unit 1 of the Haiyang plant attained first criticality - a sustained chain reaction - at 10.42am yesterday. The reactor is now in "a state of stable low-power operation", it said, adding that after completing a series of low-power physics tests, the unit's turbines will be driven for the first time using nuclear-generated steam and grid connection work will commence.

Synchronisation to the electricity grid will be followed by gradual power ascension testing until all testing has been safely and successfully completed at 100% power.

The loading of the 157 fuel assemblies into the core of Haiyang 1 began on 21 June. The unit is expected to begin operating by year-end.

The loading of fuel assemblies into Haiyang unit 2 began at 3.26pm yesterday following approval from the National Nuclear Safety Administration and the Ministry of Ecology & Environment. Haiyang 2 is expected to start up next year.