Nuclear energy is the energy in the nucleus core of an atom and it can be obtained from the splitting or joining of atoms. Atoms are tiny units that make up all the matter in space and it is the energy that holds the nucleus of the tiny atoms in the universe together. Nuclear energy can be used to generate electricity from the large amount of energy released from the atoms. Aside electricity production, nuclear energy has other benefits including sterilization of medical equipment, cheap and portable water through desalination, transportation, radioisotopes for cancer treatment, and other non-electric applications. There are two ways of getting nuclear energy i.e. either by nuclear fission or nuclear fusion.
Nuclear fusion
The energy released is as a result of the combining or fusing two daughter/smaller atoms such as hydrogen and helium atoms to form one parent atom thereby releasing a large amount of energy (heat) without emitting radiations (Alpha, Beta, Gama, X-rays). Nuclear fusion reaction occurs in the sun and stars with hydrogen atoms used as fuel and helium as waste generated. This method of generating nuclear energy is under research (prototype built in Oak lab for research) and has not been commercialized yet.
Nuclear fission
This involves the splitting of a parent atom such as uranium and plutonium or large atoms into two daughter atoms thereby releasing a large amount of energy in a form of heat and emitting radiations (Alpha, Beta, Gama, X-rays) as a by-product when it is allowed to collide with a neutron. All commercial operating nuclear power reactors use this method to generate heat.
How electricity is generated by a nuclear power plant
Nuclear power plants sustain nuclear fission chain reactions to produce electricity. During fission chain reaction heat is generated and the heat is made to boil water into steam which turns the blade of a steam turbine. The turning of the turbine blades powers the generator to produce electricity. The rest of the steam is condensed back into water in a separate structure, cooled down, and reused to generate steam again.