Workers in the control room mark the unit's attainment of first criticality (Image: CGN)
China's National Nuclear Safety Administration (NNSA) granted CGN an operating licence for Fangchenggang 4 on 27 February, allowing the loading of fuel into the reactor's core to begin. The fuel loading process was completed on 2 March.
The NNSA subsequently conducted an inspection of Fangchenggang 4 from 26-29 March to assess its readiness for criticality. The regulator announced on 1 April that the start up of the reactor could commence.
CGN said the 1180 MWe (gross) pressurised water reactor reached criticality for the first time at 7.08pm on 3 April, "marking that the unit officially entered the power operation state".
Fangchenggang units 3 and 4 (Image: CGN)
First concrete was poured for the nuclear island of Fangchenggang unit 3 - 39% owned by Guangxi Investment Group and 61% by CGN - in December 2015, while that for unit 4 was poured a year later. Unit 3 was originally expected to start up in 2019, with unit 4 scheduled to start up in 2020. Both their start-ups were subsequently postponed until 2022.
In January 2022, CGN announced that the start-up of Fangchenggang 3 and 4 had been put back again due to delays caused by the COVID-19 pandemic. Unit 3 achieved first criticality - a sustained chain reaction - on 27 December 2022 and was synchronised with the grid on 10 January 2023. It entered commercial operation on 25 March.
Hot functional testing of unit 4 began on 25 September last year. These tests involve increasing the temperature of the reactor coolant system and carrying out comprehensive tests to ensure that coolant circuits and safety systems are operating as they should. Carried out before the loading of nuclear fuel, such testing simulates the thermal working conditions of the power plant and verifies that the nuclear island and conventional equipment and systems meet design requirements.
The Fangchenggang plant is planned to house six reactors. The first phase comprises two CPR-1000 units which were put into commercial operation in 2016. Units 5 and 6 are expected to feature Hualong One reactors.
