How Does a Reactor Work?
Neutrons striking uranium atoms cause these atoms to fission. In the process of fissioning they produce heat in a chain reaction in a nuclear reactor. This heat is used to turn water into steam and then the steam turns turbines, which turn generators that produce electricity. Most commercial nuclear reactors use water to remove the heat created by the fission process. We call these light water reactors. The greater the nuclear reaction, the more heat is produced. The increasing heat turns more water to steam, which slows down the nuclear reaction. So the water works like a brake. It prevents the nuclear reaction from running out of control. If the water is cut off, the fission process stops. Water flowing in a closed, pressurized loop removes heat in a pressurized water reactor. The heat passes to a second water loop through a heat exchanger. The second loop stays at a lower pressure, allowing the water to boil and create steam. The steam turns the turbine generator and produces electr
