Unit 1 of latest South Korean nuclear power plant attains criticality  


South Korean utility Korea Hydro & Nuclear Power (KHNP) announced last week that the first unit at its Shin Hanul nuclear power plant (NPP) has attained criticality, or sustained chain reaction, for the first time, signalling the start of operations.  

Shin Hanul is South Korea’s 27th NPP and is to be equipped with two APR-1400 reactors of 1,400 MW capacity each. A KHNP statement said that the first unit is scheduled to be connected to the grid in June 2022. 

“In the future, Shin Hanul Unit 1 plans to produce electricity for the first time early next month after undergoing a performance test of the power plant system with safety as the top priority,” the KHNP said. 

Business Korea reported citing a KHNP official that full-scale commercial operations of the first unit are expected to start in the second half of the current year. 

South Korea’s Nuclear Safety and Security Committee (NSSC) gave its approval for the start-up of Shin Hanul unit 1 on July 9, 2021, and the KHNP began loading the fuel assemblies into the core of the reactor shortly thereafter. Following the completion of fuel loading KHNP announced in October 2021 that it was conducting reactor physics and systems testing under normal operating temperature and pressure conditions. 

The APR-1400 is a South Korean designed and developed pressurised water reactor (PWR) with a design life of 60 years. It is an evolutionary development of the 995 MW capacity OPR-1000 reactor, featuring improvements in operation, safety, maintenance and affordability.  

KHNP said that Shin Hanul 1 is the first power reactor in South Korea to achieve technological independence through indigenisation of core facilities, such as the reactor coolant pump and the plant instrumentation and control system. 

Earlier, the first two APR-1400 units in Korea – Shin Kori NPP 3 and 4 – began commercial operations in December 2016 and September 2019, respectively. Construction of two more APR-1400 units – Shin Kori 5 and 6 – began in April 2017 and September 2018, while these are expected to be commissioned in March 2023 and June 2024, respectively.  

Last month, South Korea has elected the new and explicitly pro-nuclear President Yoon Suk-yeol, who has vowed to reverse the former President Moon Jae-in’s policy of phasing out nuclear power.  

The APR-1400 design was approved in Europe in 2017, and in the US in 2019. In the first export order for this design, the United Arab Emirates (UAE) has chosen the APR-1400 reactors for its first NPP located at Barakah. The Barakah second unit was connected to the grid in March 2022 and the two units are now supplying a combined power of 2,800 MW to the UAE grid. Four reactors are planned to be installed at the Barakah plant.