Nuclear definition: it is something that comes from the nucleus. Nuclear physics is a branch of physics that studies the properties and behavior of atomic nuclei. Thus, nuclear energy is a source of energy that takes advantage of the energy inside the atom's nuclei.
Nuclear energy is the internal energy possessed by the nuclei of atoms. In general, folks use this concept to refer to harnessing this energy.
Atoms are the smallest particles in a material. They are composed of a nucleus and a cloud of electrons. The atomic nucleus comprises two sub-particles (neutrons and protons) that are held together by energy bonds. The critical element is that the creation or destruction of these bonds releases heat energy.
Nuclear technology deals with harnessing this internal energy for a wide range of uses. The best-known application of atomic energy is generating electrical energy in nuclear power plants.
Nuclear power plants are facilities where thermal energy is generated by causing atomic reactions in the nuclear reactor releasing energy. Subsequently, the thermal energy is converted into electrical energy through heat exchange and mechanical processes.
The main advantage of nuclear energy is that it is an alternative to fossil fuels. But, on the other hand, the waste generated takes millions of years to disappear.
This kind of energy does not release greenhouse gases, but it is not considered clean energy because it generates radioactive waste.
How Is Nuclear Energy Obtained?
We get nuclear energy inside the nucleus of atoms using two techniques:
Splitting the nucleus of an atom: nuclear fission
Merging the nucleus of two atoms: nuclear fusion.
When one of these two physical reactions occurs, the atoms experience a slight loss of mass. This lost mass is converted into a large amount of heat energy as Albert Einstein discovered with his famous equation E=m·c2.
Technique 1: Nuclear Fission
Nuclear fission is a way of getting the energy contained in a uranium atom by splitting the atomic nucleus into different smaller particles. This type of reaction generates a large amount of heat energy that can be used later in different ways.
One of the crucial features of nuclear fission is that it is generated by bombarding an unstable atom with a neutron. Once the nucleus has fissioned, one or two more neutrons are left free to collide with other atoms, generating a chain reaction.
The resulting particles are spent fuel (nuclear waste) that must be replaced when the ratio is too high and prevents free neutrons from finding atoms to fission.
Nuclear fission is currently the type of nuclear reaction used in all nuclear plants to produce electricity.
The first nuclear reactor was built in the United States, part of the Manhattan Project.
Technique 2: Nuclear Fusion
Nuclear fusion is the reverse process: the fusion of the nucleus of two atoms. The nuclei of atoms must be subjected to very high pressure and temperature conditions. A large amount of energy is also obtained through this type of reaction.
However, technically it has not yet been possible to build viable nuclear power reactors to produce electricity.
Nuclear physicists claim that this technique has multiple advantages compared to fission:
It is more sustainable for the environment
It would be a renewable energy source.
An example of nuclear fusion energy is the energy produced by the Sun. Nuclear fusion reactions are generated in the core of the star in our Solar System.
For What Is Nuclear Energy?
Once we know the definition of nuclear energy, we can better understand what applications it can be given. Atomic energy has a wide variety of applications. The best-known uses of nuclear energy are the generation of electricity in nuclear power plants and the military field.
In any case, some nuclear reactors have the function of generating radioisotopes for use in medicine, treatment of plagues, etc. For example, in medicine, nuclear radiation is used to perform x-rays or specific radiological treatments.
In the military field, it is used to create weapons and propulsion of vehicles. The effects that nuclear weapons can have on the population are devastating. To date, the atomic bomb has only been dropped twice (on the cities of Nagasaki and Hiroshima during World War II). Despite this, there are many treaties and agreements to regulate these activities.
Nuclear technology is also used to propel vehicles and missiles in the military because it allows excellent autonomy with very little fuel.
What Is Nuclear Fuel?
When we talk about nuclear fuel, we refer to the radioactive material used to generate nuclear reactions. Fission reactors need unstable atoms that can be easily broken.
Uranium is a chemical element found in nature and meets these conditions. However, for natural uranium to be used as nuclear fuel, it must undergo enrichment. This process makes it even more unstable and more efficient for atomic power plants.
The planet's uranium reserves are not considered unlimited, so nuclear energy is not renewable energy such as solar or wind energy.
In the case of nuclear fusion, the most optimal material is the one with the simplest atomic structure, that is, the fewest number of protons. For now, we are working mainly with two isotopes of hydrogen: tritium and deuterium, the first element in the periodic table.