Nuclear Power Animation - Boiling Water Reactors

Some nuclear reactors are known as "boiling water reactors" - or - BWR, for short. The concept of a boiling water reactor is similar to the concept of powering a steam engine.

Steam, generated by a fossil-fuel heating process, pushes the engine-to-be-powered forward. So, too, in a boiling water reactor except that nuclear fuel (not fossil fuel) heats the water. When the water boils, it produces steam. Steam spins the turbine (generator) which produces electricity.

The Fukushima Power Plant in Japan, for example, has boiling water nuclear reactors.

The U.S. Nuclear Regulatory Commission (NRC) provides more details about BWRs:


In BWRs, the water heated by fission actually boils and turns into steam to turn the generator

What happens to the steam, once it has turned the generator?

...water is converted to steam, and then recycled back into water by a part called the condenser, to be used again in the heat process.

The boiling water reactor must be carefully managed, to avoid - among other things - production of harmful radiation. The NRC continues with its description:


Radioactivity must be carefully managed because it can be dangerous if not handled properly. It can damage human cells or cause cancer over time.

Since the fission process creates radioactivity, all nuclear power plants have many safety systems that protect workers, the public and the environment. For example, systems allow the fission process to be stopped and the reactor to be shut down quickly.

Other systems cool the reactor and carry heat away from it. Barriers keep the radioactivity from escaping into the environment.
Where does the radiation go, when it's produced in a nuclear reactor? The NRC answers that question, too:


In reactors, radiation is contained inside small ceramic pellets about the size of an adult’s finger. They are placed in long metal rods inside a reactor vessel, which is enclosed in a concrete and steel containment building. These buildings have walls three to six feet thick.
Credits

Animation graphic by the U.S. Nuclear Regulatory Commission. Online, courtesy NRC.