The sun in a bottle: the world's largest nuclear fusion experiment begins in 2025

CADARACHE (France) .- In 1920, Lord Arthur Eddington, British astrophysicist who helped experimentally test Einstein's theory of relativity, said that "the stars use a vast reservoir of energy by means who are unknown to us "and adds," Sometimes we dream that the human being will learn one day to release him and use it for his benefit. "

A century later, hundreds of engineers and scientists from 35 countries are about to make it happen: in Provence, on a site of 42 hectares located in the idyllic countryside of the south of the country
la France, the construction of
ITER (abbreviations in English that correspond to
International Thermonuclear Experimental Reactor, and Latin word meaning "the way"), a company that will attempt to prove the feasibility of reproducing these stellar processes to produce electricity here on Earth. Its cost is estimated at about $ 24,000 million.

Unlike what happens in a conventional nuclear reactor, where electricity is generated by taking advantage of the energy released during the fission (breaking) of atoms, ITER will reproduce on a scale that, for the first time, a device called "tokamak" will be achieved in the world, in which energy is produced by the fusion (union) of small atomic nuclei.

The theoretical principle has already been tested in the laboratory, but only for very short periods and with a significant energy investment: up to now, the point of balance between what is needed to accelerate the particles and what is obtained with the merger has not been achieved. Scientists hope that by increasing their size, they will be able to maintain the reaction for long periods and achieve much greater efficiency. It is designed to produce ten times more megawatts than it receives.

"The energy produced by nuclear fusion is clean, it does not produce carbon dioxide, it does not leave radioactive waste, it does not run the risk of melting the reactor and its fuel (hydrogen, which is extracted from the atmosphere). 'Water is unlimited,' says Laban Coblentz, the project's communications officer, during a visit organized by the World Conference of Science Journalists, held this year in Lausanne, Switzerland.

The idea of ​​imitating the stars appeared in the middle of the last century and aroused tremendous enthusiasm. In Argentina, the Austro-Hungarian physicist Ronald Richter, settled on Huemul Island in Bariloche, even took part in a fraud that marked the history of 1948 to 1952 by claiming that he had managed to develop it. In the fifties, Soviet physicists Igor Tam and Andrei Sakharov designed the tokamak on the basis of the ideas proposed by Oleg Lavrentiev, considered the "father" of ITER, whose beginnings date back to 1986.

But decades later, the difficulties are not yet solved. The problem is that merging is not so easy to produce. It is one of the most powerful forces of nature and it resists. First, the atomic nuclei are electrically charged and do not want to join. To merge them, you have to print their speed, which is achieved by increasing the temperature. ITER must heat a gas to 150 million degrees, state of the material known as "plasma".

To confine it inside the apparatus, one will use powerful electromagnetic fields generated by gigantic magnets of hundreds of tons and about 15 meters high, arranged in a toroidal form (like a donut).

"Alignment must be done with absolute precision," explains engineer Romaric Darbour. "The operation will begin at the end of the year and should last about six months, because there can not be a difference of more than two millimeters in distance."

But if ITER is considered one of the most complex machines built in history, this major technical challenge is accompanied by an equally demanding effort in the diplomatic field, according to Bernard Bigot, general manager of the project since 2015.

"The countries participating in this project (the European Union, Russia, China, India, Korea, the United States and Japan, whose public funds are funded) represent half of population and 85% of global GDP, "he said. – They have different languages, cultures and ways of doing things. Sustaining the effort for decades is incredibly demanding and a bit chaotic, but the project is so good that it is worth trying. "

Considered the fifth most expensive in history (after the Apollo program, the International Space Station, the Manhattan Project and the development of the GPS system), ITER aims to test all the elements necessary for the construction and operation of a reactor. commercial nuclear fusion. It is expected that in 2025, the first plasma can be generated and that it will then take 10 years to adjust all the processes and start the operations.

"It will be like the first Wright brothers plane," said Canadian physicist Michel Laberge, who had explained to the TED that he was trying to achieve nuclear fusion. He could not perform a transatlantic flight, but he showed that it was possible. "Others point out that if it works, it will be the solution to global energy problems, but otherwise, it will be the most expensive failure in history.