A single hour of sunlight has enough power to give the earth energy for an entire year. Why is sunlight so powerful? Because it is derived from a reaction called nuclear fusion.
This process, which has the potential to generate eternal energy, is regarded as the holy grail of the energy industry and several of the world's brightest senses are bound to try to develop it.
In an interview with the BBC at the end of 2016, the famous British physicist Stephen Hawking, who said in March last year, said that the technology that allows to generate nuclear fusion is the most promising for mankind.
"I would like to see the development of fusion energy"he replied and advised on the perception that could most change our society.
"The nuclear fusion would be a source of practical energy that would give us an untouched amount of energy without polluting or generating global warming," he said.
Unlike traditional nuclear energy, which is generated by separating atoms, a process called fission, this new energy source is created by fusion, that is, by uniting the atoms.
More concrete joining of hydrogen to produce helium, a reaction that releases huge amounts of energy, just like what is happening in the sun.
The idea is essentially to create "microsols" on earth.
The race to reach the Holy Grail
Today there is more than 25 private companies dedicated to this purpose, several of them funded by some of the world's best-known entrepreneurs, such as Bill Gates (Microsoft), Jeff Bezos (Amazon) and Peter Thiel (PayPal).
The first private project was Tri-Alpha Energy (or TAE Technologies), based in California, USA, which has been around for two decades.
One of his most famous investors was co-founder of Microsoft, Paul Allen, who died in October in October.
A heavyweight in the sector is Commonwealth Fusion Systems, a start founded by six professors from the prestigious Massachusetts Institute of Technology (MIT).
Although it was only created a year ago, it is considered to be one of the most ambitious projects, as it aims to create a reactor prototype for 2025.
Gates and Bezos are two of those who finance this company together with other well-known entrepreneurs like Richard Branson and Michael Bloomberg.
also Some oil companies begin to invest in a future without fossil fuels. According to Bloomberg Agency, Italy's Eni SpA led a group investing $ 50 million in Commonwealth Fusion Systems last March.
However, some experts believe that the most likely project will not be in the private sector.
It's about the conversation International Thermonuclear Experimental Reactor (ITER, for its acronym in English), built in Cadarache, in southern France, with a budget of $ 23,000 million.
35 countries cooperate in this scientific experiment, which began more than three decades ago.
Those responsible for ITER appreciate having a large-scale reactor ready by 2050.
Several countries also develop own initiatives. Last April, the BBC was able to access the facilities in Anhui Province, China, where researchers from that country They claim that they are more advanced than their peers in the United States, the European Union (EU), Japan, South Korea and Brazil.
But all these projects face the same problem, which strange is not how to achieve nuclear fusion.
The big challenge is how to generate more energy than is spent in the process
The merger is based on heaters at very high temperatures, which exceeds hundreds of millions of degrees. In that state, matter is called plasma.
Unlike the sun, the soil does not have the prerequisites to keep that plasma warm. To achieve this, the plasma must be isolated from other materials. For this, some special cameras in the form of a ring calledtos tokamak.
tokamak they use powerful magnets to create a magnetic field that keeps the plasma isolated. The problem is that today these cameras use more energy than they manage to produce.
The solution pointed out by companies like Commonwealth Fusion Systems to use better magnets, but the truth is that no one has managed to overcome this major obstacle.
Something like the creator of Tesla, Elon Musk, believes it would be necessary to invest in creating better solar panels and batteries to catch the sun's energy, instead of wasting money trying to reproduce our star.
However, the IP Group investor told the Bloomerg Agency that although fusion energy takes longer than desired, many of the innovations created for this industry they turn out to be very lucrative.
"Research companies patent many of their creations, from software that simulates plasma combustion to 150 million degrees centigrade to a new type of magnet that has medical applications," Bloomberg reported.
Meanwhile, we have to wait to know about Professor Hawking's desire for unlimited and clean energy to be realized.
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