Global nuclear reactor median construction time 1981-2023
Nuclear reactors connected to the grid in 2023 had a median construction time of 121 months, or almost 11 years. This was the highest figure in the period, followed by a construction time of 120 months between 1996 and 2000.
Nuclear reactors with longest construction time
In 2022, Finland’s Olkiluoto 3 and France’s Flamanville 3 were the world’s nuclear reactors with the longest actual construction time compared to the projected schedule. The two plants started operations in 2023 and 2024, respectively. Shin Hanul 2, South Korea, was connected to the grid in 2023 after 126 months of construction works.
Nuclear reactors under construction worldwide
More than one-third of the nuclear units under construction globally as of 2024 were located in China, which also recorded one of the lowest mean construction time for nuclear reactors worldwide. By comparison, the construction time for reactors in the United States averaged almost 43 years, or seven times the same value in China.
