The raw material used to create fuel for nuclear power stations is uranium ore. After mining, the ore is crushed and mixed with chemicals to produce a material known as yellowcake, which is further processed to increase its potency as fuel.
This 'enriched' uranium is formed into ceramic fuel pellets of uranium dioxide, which are then encased in metal rods. These rods are grouped together to form fuel for use in a nuclear reactor. Positioning arrays of the fuel closely together enables a self-sustaining reaction, which can be slowed down or stopped using control rods.
This nuclear reaction involves the uranium atoms splitting and releasing heat, which is used to make steam. The steam drives turbines connected to a generator, which produces electricity.
Uranium is ubiquitous in the Earth's crust, showing up in anything from seawater to granite rocks. But turning it into nuclear fuel requires some special processes.