For decades the scientific community has dreamed of achieving nuclear fusion. A process that, if achieved, could become a clean and practically infinite source of energy. Over the years, laboratories around the world have worked to understand how this phenomenon works and, above all, how to carry it out to solve our energy needs.
The researchers argue that we are very close to the ignition threshold . That is, from the moment in which the energy produced exceeds that used to cause the reaction. As on other occasions, engineers and scientists are inspired by the mechanisms used by nature to offer solutions to the needs of human beings. To be more exact, a nuclear fusion reactor mimics the phenomena that occur in the core of stars.
Mimicking the natural fusion of stars
Engineers and scientists who are working on the design and construction of experimental nuclear fusion reactors try to mimic what happens inside stars in order to obtain a large amount of energy.
For example, the EAST (Experimental Advanced Superconducting Tokamak) project , developed by China and known as what could be an “Artificial Sun”, aims to create almost unlimited clean energy. “The recent operation lays a solid scientific and experimental foundation for the operation of a fusion reactor,” Gong Xianzu, a researcher at the Institute of Plasma Physics of the Chinese Academy of Sciences, who led the latest experiment, told Xinhua.
An artificial sun that has multiplied by five the temperature of the Sun for more than 17 minutes, reaching temperatures of 70 million degrees Celsius. A process that does not require fossil fuels and does not leave residues.
JET reactor
But it’s not the only scientific experiment to mimic the way the Sun feeds itself. The UK-based Joint European Torus (JET) reactor recently opened the door to clean and nearly unlimited energy by producing 59 megajoules of energy during a 5-second burst of nuclear fusion. A figure that means doubling the previous record of 21.7 megajoules set by the facility in 1997.
The process that powers stars brings together hydrogen atoms at temperatures ten times higher than the Sun’s, which then bond together to release a large amount of energy. “We’ve shown that we can create a mini-star inside our machine and hold it there for five seconds and get high throughput, which really takes us into a new realm,” explained Dr. Joe Milnes, JET Reactor Laboratory Operations Manager. .
One of the greatest advantages of nuclear fusion is that it does not require an abundance of fuels and the amounts of waste it generates are small , short-lived radioactive waste . In addition, it does not produce greenhouse gases.
JET reactor
laser-driven nuclear fusion
The promises of nuclear fusion are seen by many as the answer to the energy crisis we are going through right now. While some people have already made the move to solar-powered self-consumption, experiments set up at the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory in California, USA, have validated a way to produce nuclear power from laser driven fusion.
A milestone that has been on the cover of the journal Nature , in which it is shown that the plasma is compressed and heated, being able to supply its own heat. Like the studies cited above, the engineers and physicists involved in this project are trying to mimic what happens inside stars.
One of the most critical steps is to have a net generator of energy, “a burning plasma in which nuclear fusion is the main source of heat to keep the fuel in a plasma state hot enough to allow further fusion reactions.” ”. Alex Zylstra and his team have managed to take this big step in the laboratory. The experiment detailed in Nature uses the energy of 192 laser beams to heat the inside of a hollow cylinder very quickly, generating X-rays. As a consequence, the hydrogen isotopes fuse “producing a neutron and an alpha particle, which is the nucleus of a helium atom. The alpha particles collide with the plasma, self-heating the fuel.”
Scientists began working on nuclear fusion nearly 50 years ago, around which time the first magnetic confinement techniques emerged. However, despite the advances cited in these studies, there are still enormous challenges that must be resolved before a commercial nuclear fusion reactor can see the light of day.