Info: Nuclear Fuel Management

Fuel assembly

This is fuel assembly, although a real one would be 12 feet tall. In each rod are fuel pellets made out of a compound of enriched uranium. There are 193 of these fuel assemblies held underwater in the Seabrook Station power plant, which generates more than 1,200 megawatts.

Control rods

Nuclear power plants are designed to provide heat, and thus power, at a steady rate, called "baseload" power in the industry. But the system needs to be slowed down sometimes or shut down for refueling. The control rods are the metal tubes that fit over fuel rods below them. They are made of an alloy that absorbs the neutrons being thrown off by the nuclear reaction in the reactor to slow the rate of fission. Plant operators can also release boron into the reactor water, which also slows the pace of fission.

Fuel pellet

This is how big a pellet for a fuel assembly is. A pellet this size holds as much energy as a ton of coal, according to the guide at the Seabrook Station power plant.

Turbine building

The main purpose of nearly all power plants is to make steam to drive a turbine seen in the half-domed assembly in white in the middle of this picture. In the case of a nuclear plant, it's the heat from the controlled splitting of atoms that is generating the heat. That heat is transferred to a separate water loop to turn it into steam, which is then sent through the spinning turbine to generate electricity.

Resources: Dome Over Nuclear Reactor