The uranium fuel is produced into ceramic pellets where as these pellets are about the size of your fingertip, but each one produces the same amount of energy as 150 gallons of oil. These energy-rich pellets are stacked back-to-back in the 12-foot metal fuel rods which are called a fuel assembly.
A nuclear power plant generates electricity by using the heat obtained from fission reaction; usually by using the uranium-235 (U-235) as fuel. Fission generates the heat in a reactor just as coal generates heat in a boiler. This heat is used to boil water into steam and the steam turns huge turbine blades. As they turn, they drive the generators that make electricity. Later, the steam is changed back into water and cooled in a separate structure at the power plant named as a cooling tower and this water can be used again and again.