What is nuclear energy? A common nuclear energy definition that is frequently given: nuclear energy is the internal energy in the atomic nucleus, that is the central part of an atom. Atoms are the smallest particles in which a material can be divided. The nucleus of an atom is composed of two subparticles: neutrons and protons. These subparticles are held together due to energy links. At the moment in which these bonds are modified, a large amount of thermal energy is released in the form of heat.
Nuclear technology deals with the use of this internal energy for a wide variety of applications. The most well-known use of nuclear energy is the generation of electric power in nuclear power plants.
Nuclear power plants are installations where heat is obtained causing nuclear reactions in the nuclear reactor with which later, through thermodynamic and mechanical transformations, electric power will be obtained.
Ways of harnessing nuclear energy
In order to take advantage of the nuclear energy present in the nucleus of atoms, it can be done in two ways: splitting the nucleus of an atom or fusing the nucleus of two atoms. In the first case we call it nuclear fission and in the second nuclear fusion.
When one of these two physical reactions occurs (nuclear fission or nuclear fusion) the atoms experience a slight loss of mass. This mass that is lost becomes a large amount of heat energy as Albert Einstein discovered with his famous equation E = mc2.
What is nuclear fission?
After knowing what is nuclear energy we can make us a more especific question: what is nuclear fission? A good ferninition of nuclear fission is that the nuclear fission is the division of the nucleus of an atom into different smaller particles. This type of reactions generates a large amount of heat energy that later can be used in different ways.
One of the most important characteristics of nuclear fission is that it is generated by bombarding an unstable atom with a neutron. Once the nucleus has been fissured, in addition to particles one or two more neutrons remain free that can collide with another atom and generate more chain fissions.
Currently, nuclear fission is the type of nuclear reaction that is used in all types of nuclear power reactors.
What is nuclear fusion?
Nuclear fusion is the reverse process. The objective of the fusion reactions is to submit the nucleus of two atoms to physical conditions in which the nuclei are fused between them obtaining a single atom. A large amount of energy is also obtained by this type of reaction.
The energy produced by the Sun, for example, comes from nuclear fusion reactions.
The use of nuclear fusion would be much more beneficial than the use of nuclear fission (more sustainable for the environment, better performance, etc.). Unfortunately, currently reproducing nuclear fusion reactions artificially and sustainably is still not feasible so that all nuclear reactors are fission.
What is nuclear fuel?
We refer to nuclear fuel to the material that is used to generate the nuclear reactions. As we have said, nuclear power reactors generate nuclear fission reactions. Therefore, for this type of reactions you need a material, an atom, that is very unstable; that is so unstable that with colliding with a single neutron it breaks.
The vast majority of nuclear power reactors use enriched uranium as a nuclear fuel. Uranium is a very unstable element that occurs naturally. In spite of being unstable, it undergoes an enrichment process that makes it even more unstable and, therefore, more efficient for nuclear power plants. that following a certain process is enriched to make it more unstable.
The uranium reserves of the planet are not considered unlimited, so nuclear energy is not considered a renewable energy such as solar or wind energy. In the case of nuclear fusion, the most optimal material is that which has a simpler atomic structure, that is, a lower number of protons. In this way, it is easier to combine with another atom.
Uses of nuclear energy
After knowing the nuclear energy detinition, let's go to understant in which uses can it works. Actually, nuclear energy has a wide variety of applications. The most important one is the generation of electricity in nuclear power plants and in the military field.
Anyway, some nuclear reactors have the function of generating radioisotopes for use in the field of medicine, treatment of pests, etc. In medicine, nuclear radiation is used to perform radiographs or certain radiological treatments.
In the military field it is used to create weapons and also for the propulsion of vehicles. The effects that nuclear weapons can have on the population are devastating. To this day, the atomic bomb has only been launched twice (over the cities of Nagasaki and Hiroshima during World War II). Despite this, there are a large number of treaties and agreements to regulate these activities.
In the military field. Nuclear technology is used for the propulsion of vehicles and missiles because it allows to have a great autonomy with very little fuel. We have an example in nuclear submarines. The first nuclear submarine in the history of nuclear energy was the Nautilus.