United States Nuclear Regulatory Commission - Protecting People and the Environment
Home > NRC Library > Basic References > Glossary > Boiling-water reactor (BWR)

Boiling-water reactor (BWR)

A common nuclear power reactor design in which water flows upward through the core, where it is heated by fission and allowed to boil in the reactor vessel. The resulting steam then drives turbines, which activate generators to produce electrical power. BWRs operate similarly to electrical plants using fossil fuel, except that the BWRs are powered by 370–800 nuclear fuel assemblies in the reactor core. For additional detail, see Boiling Water Reactors (BWRs).

Page Last Reviewed/Updated Wednesday, April 02, 2014