Fukushima Daiichi meltdown (2011)
A magnitude 9.0 earthquake and tsunami knocked out external power and backup generators at Japan's Fukushima Daiichi plant, causing three reactor meltdowns and a major radiation release.
More than 150,000 people evacuated from the surrounding area; large zones remain contaminated.
Global nuclear safety standards were overhauled, with new requirements for backup power and emergency preparedness.
Fukushima showed what happens when a nuclear plant loses all cooling power. Zaporizhzhia's reliance on diesel generators is a direct parallel to the backup system that failed in Japan.
