Generating Electricity with Nuclear Power

Most power plants produce electricity by first boiling water to produce steam.  The steam is used to spin a turbine.  The shaft of the turbine spins the generator (a large coil of wire) between two magnets.  The spinning coil of wire generates electricity.  The main difference between a nuclear power plant and other kinds of power plants lies in the way the water is heated to steam.  In a nuclear power plant, heat is produced by splitting atoms, rather than, for example, the combustion of oil, gas, or coal in a, respectively, oil, gas, or coal-fired plant.

When the uranium atom splits, it releases energy and two or more neutrons from its nucleus. These neutrons can then hit the nuclei of other uranium atoms causing them to fission. The sequence of one fission triggering others, and those triggering still more, is called a chain reaction. When the atoms split, they release energy in the form of heat. The heat is transferred from the reactor core to the steam generator. Here, it’s converted to high pressure steam which turns the turbine in the electric generator.

Uranium is an element that can be found in the crust of the earth. This element, quite abundant in many areas of the world, is naturally radioactive. But uranium as found in nature cannot just be thrown into a reactor the way coal is shovelled into a furnace. Today’s nuclear fuel consists of ceramic pellets about the size of the end of one’s finger that are formed from naturally-occurring uranium concentrates through a series of chemical and physical processes (see Nuclear Fuel Cycle).

As fuel is burned within a reactor, it accumulates fission products that inhibit the efficiency of the chain reaction. Eventually, the spent fuel must be removed and replaced with fresh fuel.