What is "the most promising technology for humanity" according to physicist Stephen Hawking

One hour of sunlight is enough to power the Earth for a whole year. Why is sunlight so powerful? Because it results from a reaction called nuclear fusion.

This process, which has the potential to generate eternal energy, is considered the holy grail of the energy industry and many of the brightest minds in the world are determined to try to develop it.

] In an interview with the BBC in late 2016, the famous British physicist Stephen Hawking, who died last March, said the technology to generate nuclear fusion was the most promising for humanity .

" I would like to see the development of fusion energy ," he replied, consulted on the idea that could most transform our society.

"Nuclear fusion would be a source of practical energy that would give us an inexhaustible amount of energy, without polluting or generating global warming," he said.

Unlike traditional nuclear energy, which is generated by the separation of atoms – a process known as fission – this new source of energy is created by the fusion of atoms.

Although it was created a year ago, it is considered one of the most ambitious projects because it aims to create a prototype reactor for 2025.

Gates and Bezos are two of those who finance this venture, along with other famous entrepreneurs such as Richard Branson and Michael Bloomberg.

Similarly some oil companies begin to bet on a future without fossil fuels . According to the Bloomberg agency, the Italian Eni SpA led a group that had invested 50 million US dollars in Commonwealth Fusion Systems in March

. An international effort

But some experts believe that the project that has the best chance of progressing is not private sector.

The so-called International Thermonuclear Experimental Reactor (ITER ), under construction in Cadarache, Southern France, with a budget of $ 23,000 million US.

Thirty-five countries collaborate in this scientific experiment launched more than thirty years ago

ITER estimates that a large-scale reactor should be ready by 2050.

Several countries are also developing their own initiatives. Last April, the BBC was able to access the facilities of Anhui Province in China, where scientists from that country claim to be more advanced than their peers in the United States, in the United States. European Union (EU), Japan, South Korea and Brazil

The problem

But all these projects face the same problem, which is not interesting, how to achieve nuclear fusion.

The big challenge is generating more. energy spent during the process.

The fusion is based on the heating of materials at very high temperatures, exceeding hundreds of millions of degrees. In this state, the material is called plasma.

Unlike the Sun, the Earth does not have the necessary conditions to keep this plasma warm. To do this, the plasma must be isolated from other materials. To do this, some special cameras shaped ring are used to s tokamak .

The Tokamak uses powerful magnets to create a magnetic field that keeps the plasma isolated. The problem is that today, these cameras consume more energy than they manage to produce

Companies such as Commonwealth Fusion Systems suggest to use better ones. magnets, but the truth is that nobody has managed to overcome this big obstacle.

Some, like the creator of Tesla, Elon Musk, believe that it would be necessary to invest to create better solar panels and batteries to capture the sun's energy [1945900] instead of money to try to replicate our star.