Nuclear Energy

Coal, Natural Gas, Nuclear. What do they all have in common? They are all ways to make, electricity, yes. But, the electricity is made the same – by boiling water. How the heat is created to boil the water is different. In the coal industry, they burn coal, which creates heat, which is used to boil water. The steam then turns generators, which will create electricity. Natural gas works the same, except that it burns Natural Gas, not coal.

The energy or heat in nuclear power is created by splitting atoms (fission), or by putting atoms together (fusion). Fusion is experimental, and is not used in any commercial nuclear power plant. You can't just split any atom, though. Uranium is used in all western hemisphere reactors, and most other nuclear reactors around the world. You don't want to use plutonium because it is very unstable, and the nuclear process (fission) can go out of control. Uranium is much, much more stable, making it safer. When a neutron is fired at uranium, it releases kinetic energy, gamma radiation, and more neutrons. The extra neutrons created then split more nuclei form the uranium (U-238), and a chain reaction occurs. This will happen until there is no more nuclei. To sum it up, when uranium absorbs a neutron, it splits into smaller nuclei, which releases more neutrons, kinetic energy, and gamma radiation. Kinetic energy is converted into thermal energy. This is created by kinetic energy colliding with nearby atoms. Heat is created by radioactive decay. The heat is taken away by in most (75%) of nuclear power plants water, but graphite can be used, also.

There are various types of reactor design, but there are two that are used most: Pressurized Water Reactor and Boiling Water Reactor. In a Pressurized Water Reactor (PWR), everything is stored in a pressure vessel, which contains the nuclear fuel, control rods, moderator, and coolant. The hot, radioactive water that leaves the pressure vessel is looped through a steam generator, which will heat a second loop of non-radioactive water, which will turn turbines. The radioactive water will then loop through the pressure vessel, to be reheated. In a Boiling Water Reactor (BWR), the water is boiled right in the pressure vessel, which will run the turbines, to create electricity. The most popular type of reactor design in the US is the PWR, with the BWR following second.

To control, slow or stop the chain reaction, Control Rods are used. They are made of a nuclear poison, which absorbs the neutrons, which slows the chain reaction. They can be inserted farther into the reactor to further slow the reactivity. If they are inserted far enough, the chain reaction will eventually stop.