What We're Showing
This chart visualizes the age and electrical capacity of the world’s 416 nuclear reactors, using data from the Power Reactor Information System. Each bubble represents a cohort of reactors of the same age, with bubble sizes corresponding to total net electrical capacity (in megawatts).
Key Takeaways
- The global reactor fleet is aging, with more than two-thirds of the world’s nuclear reactors over 30 years old.
- The average nuclear reactor is around 32 years old.
- Reactors built in the last 10 years have a higher average electrical capacity per unit (1000+ MW) than those built 50+ years ago.
- The large number of 30-plus-year-old nuclear reactors reflects periods of nuclear expansion in the 1970s and 1980s, followed by a lull and resurgence over the last decade.
- The number of operational reactors is down from 422 in 2023 to 416 in 2025, with a few reactors shutting down in Germany.
