Nuclear energy is created by splitting uranium atoms by a process called nuclear fission. This process releases energy in the form of heat that can then be used to create electricity. Nuclear power accounts for approximately 19% of the US electricity production. More than 100 nuclear plants are currently in operation in the US, however, no nuclear power plants have been built since 1996.
Uranium is a nonrenewable resource that cannot be replenished on a human time scale. Uranium is extracted from open-pit and underground mines. The uranium ore is processed into dense uranium oxide pellets. This uranium enrichment process generates radioactive waste.
At the power plant, the uranium oxide pellets are bombarded with neutrons, causing the uranium atoms to split and release both heat and neutrons. These neutrons collide with other uranium atoms and to release additional heat and neutrons in a chain reaction. This heat is used to generate steam, which is used by a turbine to generate electricity.
Nuclear power plants do not emit carbon dioxide, sulfur dioxide, nitrogen oxides, or any other dangerous or harmful gases. Nuclear power plants use large quantities of water for steam production and for cooling. Coal and natural gas plants would also draw a comparable amount of water.
Once every two years nuclear reactors must be shut down to remove and replace the spent uranium. This spent fuel has released most of its energy as a result of the fission process and has become radioactive waste. Radioactive waste is then stored in steel-lined concrete vaults. These wastes will remain radioactive for many thousands of years.
I personally believe that nuclear is a reasonably clean alternative fuel. All the waste of it we control, it does not get sent up in the atmosphere. One day we will have means of using the radioactive waste we generator today into another fuel source and takeout the remaining energy from it, while cleaning it.