Uranium is the main fuel for nuclear reactors, and it can be found in many places around the world. In order to make the fuel, uranium is mined and goes through refining and enrichment before being loaded into a nuclear reactor.
The vast majority of nuclear power reactors use the isotope uranium-235 as fuel; however, it only makes up 0.7% of the natural uranium mined and must therefore be increased through a process called enrichment. This increases the uranium-235 concentration from 0.7% to between 3% and 5%, which is the level used in most reactors.
Video Credit: Urenco
