South Korea begins construction of another new nuclear unit at Shin Hanul

A new nuclear unit at South Korea’s Shin Hanul power plant has reached a significant milestone. A year after construction began on the third APR-1400 unit, technicians at the site have officially begun construction of its fourth sister unit. KHNP plans to complete the 1400 MW unit in 2033. The country is currently building four new nuclear units and is working to prepare further nuclear projects.

South Korean energy company Korea Hydro & Nuclear Power (KHNP) announced that it had officially begun construction of another new nuclear unit. On 29 May, technicians poured the first concrete for the reactor building of the fourth unit at Shin Hanul power plant. The APR-1400 unit, designed for an operating life of 60 years, will have an installed capacity of 1400 MW.

“Units 3 and 4 at Shin Hanul nuclear power plant are a firm foundation that will support Korea’s energy future, just like the foundation concrete we are pouring now,” said Kim Hoe-cheon, president of KHNP.

The authorities issued construction permits for the two new units at Shin Hanul power plant in September 2024. KHNP officially began construction of the plant’s third unit in May 2025. The company expects the units to enter service in 2032 and 2033. The first two Shin Hanul units, also equipped with APR-1400 reactors, began generating electricity in 2022 and 2023.

“Particularly amid growing instability in the global energy supply chain, we expect the units to serve as a reliable shield protecting the national economy. They will strengthen energy security while ensuring a stable and affordable energy supply,” KHNP said in a press release.

South Korea’s nuclear construction

South Korea currently has 26 operating nuclear units, four of which are APR-1400s. Another four APR-1400s are under construction at the Saeul and Shin Hanul power plants. Nuclear energy development in the country went through a five-year hiatus from 2017 to 2022, during President Moon Jae-in’s term in office. Preparations for the Shin Hanul 3 and 4 project were therefore suspended, and KHNP did not return to it until 2023.

“We will build world-class nuclear power plants, making safety our top priority and fulfilling our mission to contribute to achieving the national carbon neutrality target,” Hoe-cheon added.

In addition to conventional nuclear reactors, the South Korean government is also planning to build small modular reactors to further increase nuclear power’s share of the energy mix.