After uranium is mined and placed inside a nuclear reactor, the control rods in the reactor are raised. Then, a neutron or other subatomic particle is sent into the nuclear reactor to make a uranium atom split. This produces a chain reaction of uranium atoms sending neutrons to one another, causing the atoms to split and release heat. The heat warms water in the tubes around the reactor, producing steam. Steam then turns the reactor's turbines, and they produce electricity. Electricity is then used as power. Water is also used as a coolant later in the process to help slow the neutrons in their unstable state.
About 15 percent of the world's electricity is produced from nuclear energy, with the United States, France and Japan accounting for half of the overall figure, according to the International Energy Agency. Since the Chernobyl disaster of 1986, nuclear power plants have seen an increase in safety and security. Whereas the reactors of the 1980s required constant intervention to keep the uranium from producing too much energy too quickly, the plants of today require human intervention to create energy at all and automatically shut down if unattended.
The major environmental benefit of nuclear power at this time is the fact that it produces very few carbon emissions. Nuclear power plants are also safe structures, and the reactors are designed to stop the fission process by reinserting the control rods if any untoward environmental factors present themselves. Many countries have also perfected a method of refining nuclear waste to acquire any remaining uranium to reuse in the process, thus reducing the quantity (though not improving the quality) of the waste.
After the uranium atoms are split, they leave behind radioactive waste that stays active for up to tens of thousands of years. Spent fuel cells require very specific infrastructure to keep the harmful substance contained. Waste cools for several years in a concrete tank and is then mixed with glass and cooled further. The steel containers are stored above ground within concrete shields. However, high-level waste, the most concentrated in radioactivity, is produced by refining nuclear waste to extract the last bits of uranium, and this substance eventually corrodes every container in which it is placed. This means that every implemented storage solution is a temporary fix and will need to be replaced.