So you probably know by now nuclear power generation starts with a uranium atom, but do you know where that uranium atom comes from? Or how uranium gets to a nuclear plant? Or what happens to it when it gets to the plant?
Here’s the life cycle of uranium. Where it starts. And, how it becomes the fuel for our reactors to generate clean, life-essential electricity around the clock to power the lives of our communities.
Uranium is a dense heavy metal found in nature. It’s used in nuclear power generation because its nucleus is perfect for the fission process — being split apart by impact from a neutron. The most abundant uranium isotope is uranium-238; nuclear reactors use uranium-235 to generate heat. (The difference between these two isotopes is the number of neutrons in their nuclei; both have 92 protons.)
Step 1. Mining uranium. Most uranium is mined from ore deposits in Africa, Canada, Australia and Kazakhstan.
Step 2. Concentration. The ore is then dried, concentrated and sent to a conversion facility, where it’s mixed with fluorine gas to create uranium hexafluoride gas, which is more easily enriched.
Step 3. Enrichment. It’s enriched at an enrichment facility. Uranium used to generate electricity has to have more uranium-235 isotopes than is found in nature, so it’s enriched to 3-5%, up from its natural state of 0.7%, using a gas centrifuge. The uranium hexafluoride gas is spun at an extremely high speed. The centrifugal force separates uranium-235, which is lighter, and uranium-238, which is heavier. The uranium-235 is spun until it reaches the desired enrichment.
Step 4. Fabrication. Now the enriched uranium heads to a fabrication facility, where it’s chemically converted to a very fine powder which is molded into a ceramic pellet about the size of a pencil eraser. Pellets are stacked end-to-end in zirconium alloy-cladded fuel rods. The rods are then bundled together into a fuel assembly.
Step 5. The fuel assemblies are transported to a nuclear plant.
So, what happens after the fuel assemblies arrive at a nuclear plant … Watch and learn.