NSSC on EnergyNote

Why four Korean reactors are idle: expired licenses, a twice-deferred accident plan, and Wolsong 2 on November 1

Thu, 08 Oct 2026 09:00:00 +0900

KRW 1,891.9 billion, about $1.4 billion. That is the value of the electricity four Korean reactors could not sell between their license expiry dates and September 22, 2026, according to the office of Rep. Hwang Jung-a, working from data supplied by Korea Hydro & Nuclear Power (KHNP), the state utility that operates every Korean reactor, and it counts foregone sales, not cash that left anyone’s account.

i-SMR licensing tracker, October 2026: where Korea's standard design approval stands

Sat, 03 Oct 2026 09:00:00 +0900

Seven months. That is how long Korea’s first small modular reactor design has been in front of its regulator, and the next two dated deadlines both belong to the developer, not the regulator.

This is a dated status check, not an explainer. The background on the i-SMR, the institutions and the program’s wider setting is in our baseline post on Korea’s SMR program. Everything below is as of October 2, 2026, and where I could not confirm something, I say so.

How Korea's reactors are designed for earthquakes and tsunamis: the numbers, site by site

Wed, 30 Sep 2026 09:00:00 +0900

At 8:32 p.m. on September 12, 2016, a magnitude-5.8 earthquake, the strongest ever instrumentally measured in South Korea, struck about 27 kilometers from the Wolsong nuclear site outside Gyeongju, and instruments there recorded shaking strong enough to trigger a manual reactor shutdown. Four units went off line as a precaution; none was damaged, and the recorded shaking stayed below the plant’s design limit. It was still the closest a Korean reactor site has come to testing the number engineers had written into its blueprints decades earlier.

How Korea decides whether a 40-year-old reactor keeps running: the continued-operation process, step by step

Sun, 13 Sep 2026 13:51:00 +0900

On September 11, 2026, Hanbit unit 2 on Korea’s west coast reached the end of its 40-year operating license and stopped. Nothing had broken. The unit joined Kori 3, Kori 4 and its sister Hanbit 1 in a queue of reactors that are legally “operating” but cannot generate until the regulator says so, and that morning the regulator considered the first item in their file and put it off to a later meeting.

How a nuclear reactor gets licensed in Korea: from site to standard design approval to first power

Sun, 13 Sep 2026 13:47:00 +0900

Suppose you read that Korea “approved” a reactor this week. Five different things could have happened: a ministry approved a site plan, the regulator accepted a design, it permitted construction, it licensed operation, or it cleared a unit to restart after a trip. Korean headlines use one verb for all five.