BWR — Boiling Water Reactor
Water boils directly in the reactor vessel, producing steam that drives turbines directly. Simpler single-loop design than PWR but the steam is mildly radioactive, requiring turbine building shielding.
Key Stats
100/100
BWR — Boiling Water Reactor
Design Overview
Water boils directly in the reactor vessel, producing steam that drives turbines directly. Simpler single-loop design than PWR but the steam is mildly radioactive, requiring turbine building shielding.
Key Specifications
Typical output: 600–1,400 MWe. Operating pressure: ~70 bar. Coolant temp: ~285°C. Fuel: LEU oxide, ~2–4% U-235. Refueling cycle: 12–24 months.
Who Builds It
GE-Hitachi (ABWR, BWRX-300), Toshiba
Where It's Deployed
USA, Japan, Sweden, Finland, Germany (historical), Taiwan
Advantages
Simpler design (no steam generators). Lower pressure. Direct cycle efficiency. ABWR has strong safety systems.
Disadvantages
Radioactive turbines complicate maintenance. Lower power density. Pressure suppression pool required.
Technology reference note · Second Atomic Age Nuclear Wiki Last updated: 2026-05-10
Sources
- IAEA - Boiling Water Reactor Technology [UNVERIFIED] — Overview of BWR technology and characteristics.
- World Nuclear Association - Boiling Water Reactors [UNVERIFIED] — Detailed technical and operational information on BWRs.
- Wikipedia - Boiling Water Reactor — General encyclopedia entry on BWR design and history.
- GE Hitachi Nuclear Energy - BWR Technology — Vendor information on BWR designs including ABWR and BWRX-300.
Sources (1)
Related Notes
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