Several Components of a Nuclear Power Plant
Fuel: Uranium, in the form of pellets made of uranium oxide (UO2), serves as the basic fuel. These pellets are placed in tubes to create fuel rods, which are then assembled into fuel assemblies within the reactor core. For instance, in a 1000-megawatt electric (MWe) class Pressurized Water Reactor (PWR), there might be about 51,000 fuel rods containing over 18 million pellets.
Moderator: This is a substance within the reactor core that slows down the neutrons released during the fission process, thereby promoting more fission reactions. Typically, water serves as the moderator, but heavy water or graphite can also fulfill this role.
Control rods: Engineers craft these components from materials like cadmium, hafnium, or boron, which absorb neutrons. Operators can insert or withdraw them from the core to regulate the rate of the nuclear reaction or to stop it altogether.
Coolant: This is a fluid that circulates through the core to carry away heat generated by the nuclear reaction. In reactors such as Light Water Reactors (LWRs), the same water that acts as a moderator also functions as the primary coolant.
Pressure vessel or pressure tubes: Typically made of sturdy steel, this vessel contains the reactor core along with the moderator and coolant. In some designs, it may consist of a series of tubes that hold the fuel and guide the coolant through the surrounding moderator.
Steam generator: A crucial component in the cooling system of Pressurized Water Reactors (PWRs) and Pressurized Heavy Water Reactors (PHWRs). It uses the high-pressure primary coolant from the reactor to produce steam, which then drives a turbine in a secondary circuit to generate electricity.
Read Also: Types of Reactors
