Nuclear fusion is called the “Holy Grail” of energy because it can provide a lot of clean energy. Although it often seems like science fiction, the tone falls to “scientific” as it seeks to realize on Earth how the sun and stars generate energy. Recently, an experimental result was announced in the USA that could be decisive for the future, since for the first time in the process of nuclear fusion we received more energy than we used!

“On December 5, the National Ignition Facility at Lawrence Livermore National Laboratory (LLNL) in the United States conducted the first controlled fusion experiment that produced more energy than was used to run it. This experiment is the result of a long effort. The National Ignition Facility is considered to be the most energetically powerful laser system in the world. For this particular experiment, 192 laser beams were used to deliver 2.05 million joules (MJ) of energy to a deuterium and tritium target. Having generated 3.15 MJ of energy, the experiment showed for the first time the possibility of a net increase in energy from thermonuclear fusion,” says Ion Stamatelatos, Research Director of the Democritos Research Center, head of the Center’s research reactor laboratory, “K”, with a rich research activity in the field of thermonuclear technologies.

“The achievement of Lawrence’s Livermore Laboratory could be a fundamental building block of a larger power generation system. That is why this is an important milestone in scientific and technological efforts to develop a source of abundant and clean energy,” he adds.

But what is nuclear fusion? “This is a process in which two light nuclei fuse into one heavier nucleus, releasing a large amount of energy. During fusion, the nuclei of light atoms, such as hydrogen and its isotopes, deuterium and tritium, collide and fuse under certain conditions of high pressure and temperature, forming neutrons and nuclei of heavier atoms, such as helium, while simultaneously releasing a huge amount of energy. “, explains Mr. Stamatelatos.

“Merger is a natural process by which energy is generated in stars. On the Sun, this is due to extremely high temperatures of the order of ten million degrees Celsius and high pressure – 100 billion times greater than that of the Earth’s atmosphere. To try to recreate these conditions on Earth, scientists have used a variety of methods. The two main ones are inertial fusion and magnetic confinement fusion,” adds the director of research at Demokritos.

For the first time, the National Ignition Plant produced more energy than was consumed for the experiment.

Fusion can be considered the “opposite” of nuclear fission currently used in nuclear power plants, in which heavy nuclei such as the uranium nucleus are fissioned while simultaneously producing energy. “The disadvantage of this method is the generation of radioactive waste, which must be safely stored for hundreds of years. On the contrary, fusion does not produce long-lived radioactive waste,” emphasizes Mr. Stamatelatos.

Large nuclear fusion programs are also being carried out in Europe. However, if inertial fusion was used in the Lawrence Livermore Laboratory, then in Europe the magnetic confinement method is mainly used. In doing so, Stamatelatos explains, strong magnetic fields are used to confine the plasma in a donut-shaped device called a tokamak. “Tokamak is a Russian abbreviation meaning an annular vacuum chamber surrounded by magnetic coils. Recently, researchers from the EU-funded EUROfusion consortium. and in which our country also participates – they used the largest international tokamak, the Joint European Tor (JET), located in Culham, UK, to produce 59 MJ of fusion power in about 5 seconds. This period of time on the scale of nuclear physics is long, and the amount of energy produced is remarkable, much larger than in Lawrence’s Livermore experiment. But in JET, some of the energy used was recovered (about 67%).

Under construction is ITER, a much larger tokamak in Cadarache, in southern France. It is a mega program supported by the European Union, China, India, Japan, South Korea, Russia and the USA. Greece has been contributing to the European fusion program since 1999 with research teams from research centers and universities.

“Nuclear fusion can play a critical role in moving away from fossil fuels and meeting growing energy needs while reducing greenhouse gas emissions. Unlike solar or wind energy, it does not depend on weather conditions. It is also inherently safe, as it is not based on a chain reaction, as in the case of nuclear fission. Most fusion experiments use deuterium, which can be inexpensively extracted from water, as well as lithium, which is relatively abundant in nature,” emphasizes Mr. Stamatelatos.

Is he optimistic about the future? “While there are significant scientific and technological hurdles to overcome to achieve electricity generation, recent developments may mean we are moving closer to introducing a technology that will fundamentally change the energy landscape. The European roadmap calls for the construction of a fusion power plant in a few decades. Therefore, nuclear fusion can play an important role in achieving the goal of producing abundant energy with zero emissions in the second half of the 21st century.”

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