Nuclear fusion could be an almost unlimited source of energy, a clean alternative to today's nuclear fission reactors, which can have serious environmental consequences due to accidents or radioactive leakages, as seen in Chernobyl and Fukushima.
Among the clean energies is usually the wind or solar energy exploiting the photovoltaic panels or the tidal wave. but generally not in nuclear fusion, which must not be confused with fission, because although it is the most abundant source of energy in the universe, the one produced within the stars, it is not yet possible to attain it on Earth due to the extreme natural conditions for us in which it is produced.
But the day of pure and unlimited energy from nuclear fusion has come a step closer thanks to the experimental advanced superconductive Tokamak (East).
During four months of testing, the "Chinese artificial sun" reached a plasma temperature of more than 100 million degrees Celsius, six times warmer than the sun's interior and a 10 MW heating power. The plasma or fourth state of matter next to the solid, liquid and gas is a fluid formed by electrons and free positive ions, separated from the very high temperature.
The East – designed and developed by the Chinese – is located at the Heads of Science Institute of Hefei of the Chinese Academy of Sciences (Caships) and is an experimental facility for enterprises with the ultimate goal of producing a nuclear power fusion power reactor
The East is a reactor consisting of a hard metal center in the form of a ring or donut that reaches a state of absolute vacuum and then injected with hydrogen atoms. Subsequently, these atoms are heated by several different methods to create a plasma that is then compressed using a series of powerful superconducting magnets.
It mimics the Sun
Over time, the plasma is heated and compressed so much that the conditions inside the reactor mimic those inside the Sun, causing the atoms of hydrogen to melt, releasing huge amounts of energy.
The expectation is to build a reactor where the fusion reaction is self-sufficient and the reactor produces more energy than it consumes.
The East produced extremely high temperatures and densities for about 10 seconds by combining four different heating methods to bring matter to the plasma and to achieve the fusion process.
The East is an important tool for keeping electron temperatures above 100 million degrees Celsius over long periods of time. then knowledge on how to develop nuclear fusion reactors will be improved
Stars keep their brightness thanks to nuclear fusion, a natural process that does not produce radiation as opposed to fission used in reactors. Fusion is a complicated process of transforming hydrogen atoms into the sun that occurs in the center of the sun and the infinity of other stars. It is a cosmic process in which we owe all the energy that exists on Earth from the moment that it exists from our own life.
After the discovery of equivalence between mass and energy more than a century ago, it was possible to produce energy through nuclear fusion in the laboratory.
If all the hydrogen in a star like the Sun was transformed into a helium and the difference in mass turned into energy, it is enough to keep it warm for 10 billion years.
Nuclear fusion allows the star to shine for billions of years and also causes the creation of all the heavier elements that make up the matter.
Under certain conditions, hydrogen atoms are connected to dense clouds or pioneers, beginning to contract with the action of their own gravitational force. The contraction continues until the pressure and temperature in the center of the protostar is so high that a self-sustaining thermonuclear reaction process begins, where the hydrogen nuclei are combined to form helium nuclei. The star remains until most of the hydrogen is consumed and then gravitates again until its center is warm enough for the sun to merge to form heavier elements. The process of fuel depletion and contraction continues, passing through several cycles, each shorter than the previous one.
Sun is in the first stage of nuclear burning, about half of his life. At this stage, four hydrogen nuclei are fused to create a helium nucleus
The energy released when a helium is formed is about 25 MeV, corresponding to the mass difference between four protons and a helium plus two positrons. This action occurs in the form of kinetic energy of the gas particles and as light and light
radiating energy that diffuses towards the surface of the Sun and escapes outward.
The type of fusion reactions occurring inside the Sun is very different from that used in laboratory plasmas due to different physical conditions. In the center of the Sun, because of the high densities, reactions are still impossible in the laboratory.