Initial fuel loading completed at second San'ao unit

China General Nuclear (CGN) said the milestone, completed on 2 November, marks "the official entry of the unit into a new stage of nuclear-powered operation and commissioning. This is another key step for San'ao Nuclear Power towards the goal of achieving full completion and commissioning of the first phase of the project".

The company noted that the fuel loading operation at San'ao 2 utilised semi-automatic equipment. "After the staff completed the fuel loading sequence programming, the programme was imported into the refuelling machine's control system," CGN said. "Specialised fuel operators then controlled the equipment, sequentially transferring 177 fuel assemblies from the spent fuel pool's fuel racks to the reactor core. Notably, this loading operation also utilised a floating light gun independently developed by CGN, providing underwater illumination for the core operations and effectively ensuring the smooth progress of the loading process."

The background

On 2 September 2020, the executive meeting of the State Council approved the construction of units 1 and 2 as the first phase of the plant. China's National Nuclear Safety Administration issued a construction permit for the two units on 30 December that year and first concrete for unit 1 was poured the following day. The first concrete for San'ao 2 was poured on 30 December 2021.

Unit 1 achieved first criticality in February this year and was connected to the grid in March. The reactor was declared to be in commercial operation on 29 April.

Cold functional tests - which are carried out to confirm whether components and systems important to safety are properly installed and ready to operate in a cold condition - were completed at San'ao 2 in October last year. Hot functional tests - which simulate the temperatures and pressures which the reactor systems will be subjected to during normal operation - were completed in April this year. San'ao 2 is scheduled to begin supplying electricity in 2027.

The San'ao plant is the first nuclear power project in China's Yangtze River Delta region to adopt the Hualong One reactor design.

The construction of two Hualong Ones as units 3 and 4 of the San'ao plant was among plans for 11 reactors approved by China's State Council in August 2024. The first concrete was poured for the nuclear island of unit 3 on 19 December last year. A further two Hualong One units are planned as units 5 and 6.

Upon completion, the project will provide more than 54 TWh of electricity annually to Zhejiang Province and the Yangtze River Delta region, reducing standard coal consumption by more than 16 million tonnes and carbon dioxide emissions by more than 51 million tonnes annually, CGN noted.

The San'ao project marks the first Chinese nuclear power project involving private capital, with Geely Technology Group taking a 2% stake in the plant. CGN holds 46% of the shares of the project company Cangnan Nuclear Power, with other state-owned enterprises holding the remainder.