China reaches important milestones for new Hualong One nuclear unit

China’s new Fangchenggang 4 nuclear unit has reached two important milestones. In early April, it first achieved criticality and was then connected to the electricity grid by technicians. During the upcoming tests, the first MWh of electricity it generates will therefore be delivered to consumers. CGN began construction of its second Hualong One unit in 2016. The unit will enter commercial operation after completing the remaining operational tests.

China General Nuclear (CGN) announced that its second Hualong One unit at the Fangchenggang nuclear power plant had successfully achieved criticality. Criticality in a nuclear reactor is the state in which the fission reaction is stable and neither accelerates nor slows down. CGN began construction of two demonstration Hualong One units in late 2015 and late 2016.

"The 1,180 MWe (gross) pressurised water reactor first achieved criticality on 3 April at 19:08. This means the unit has officially entered the power generation phase," CGN said in a press release.

Just under a week later, CGN technicians connected Fangchenggang 4 to the electricity grid so it could supply the electricity it generates during the testing phase at various power levels. The unit is expected to enter commercial operation after completing all tests in the first half of this year.

The Fangchenggang power plant already has two CPR-1000 units. In addition to the two newly completed units, it is expected to have two more Hualong One units, although construction of these has not yet begun. Units 3 and 4 are 39% owned by Guangxi Investment Group and 61% by CGN itself.

China’s "unified" Hualong One design

Designs for China’s Hualong One nuclear units, also known as HPR1000, were initially developed independently. China National Nuclear Corporation was working on a unit designated ACP1000, while CGN was developing the ACPR1000. In 2012, the Chinese government ordered the programmes to be unified with the aim of accelerating construction and beginning to compete in the international market.

Despite the unification, units from the two companies differ in some respects. While CNNC has managed to bring four Hualong One units into commercial operation since 2015, CGN has so far achieved this milestone with just one.

CNNC launched its first Hualong One at its home plant, Fuqing 5, in November 2020. It was followed by a second unit at Pakistan’s Karachi plant (3/2021), Fuqing 5 (1/2022) and Karachi 3 (3/2022). CGN brought its first Hualong One into commercial operation at the end of March 2023. A further 11 Hualong One units are currently under construction in China.