One hour of sunlight has enough power to supply the Earth with energy for a full year. Why is the sun so strong? Because it arises from a reaction called nuclear fusion.
This process, which has the potential to produce lasting energy, is considered the holy cup of the energy industry and some of the world's brightest minds are bound to try to develop it.
In an interview with the BBC at the end of 2016, famous British physicist Stephen Hawking, who died last March, said that the technology that makes it possible to produce nuclear fusion is the most promising for humanity.
"I want to see the development of fusion energy", he replied, consulting on ideas that could change our society the most.
"Nuclear incorporation will be a practical energy source that will give us an unlimited amount of energy, without pollution or produce global warming," he said.
Unlike traditional nuclear energy, which is produced by separating atoms – a process known as fission – this new energy source is created by combining – that is by uniting atoms.
More concretely combine hydrogen to produce helium, a reaction that releases a large amount of energy, like what happens in the Sun.
The idea, in essence, is to create "microsoles" on Earth.
Race to reach the holy grail
Today is there more than 25 private businesses dedicated to this purpose, some of them are financed by several well-known entrepreneurs on the planet, such as Bill Gates (Microsoft), Jeff Bezos (Amazon) and Peter Thiel (PayPal).
The first private project is Tri-Alpha Energy (or TAE Technologies), based in California, United States, which has been around for two decades.
One of the most famous investors is Microsoft co-founder Paul Allen, who died last October.
The heavyweight in this sector is Commonwealth Fusion Systems, a startup founded by six prestigious professors from the Massachusetts Institute of Technology (MIT).
Although it was only made a year ago, this is considered as one of the most ambitious projects because it aims to make a prototype reactor for the year 2025.
Gates and Bezos are two of those who finance this business, along with other well-known entrepreneurs such as Richard Branson and Michael Bloomberg.
Too some oil companies are starting to bet for the future without fossil fuels. According to agent Bloomberg, Italy Eni SpA led the group that invested US $ 50 million in the Commonwealth Fusion Systems last March.
But some experts believe that the project that is most likely to move forward is not in the private sector.
It's about his calling International Thermonuclear Experimental Reactor (ITER), for an acronym in English), which was built in Cadarache, in the south of France, with a budget of US $ 23,000 million.
35 countries collaborated in this scientific experiment, which began more than three decades ago.
Those responsible for ITER estimate to have a large-scale reactor ready by 2050.
Some countries also develop their own initiatives. Last April the BBC was able to access facilities in Anhui province, in China, where scientists from that country they claim to be more advanced than their peers in the US, European Union (EU), Japan, South Korea and Brazil.
But all these projects are faced with the same problem, which is oddly not how to achieve nuclear fusion.
The big challenge is ways to produce more energy than what is spent in the process.
This fusion is based on heating matter to very high temperatures, which exceed hundreds of millions of degrees. In that situation, the material is called plasma.
Unlike the Sun, the Earth has no conditions to keep the plasma warm. To achieve this, plasma must be isolated from other materials. For this, some special camera in the form of a ring calledas tokamak.
The Tokamak they use strong magnets to create a magnetic field that makes plasma isolated. The problem is today these cameras consume more energy than they produce.
The solution shown by companies like Commonwealth Fusion Systems is to use better magnets, but the reality is that no one has overcome this big obstacle.
Some like Tesla creator Elon Musk believe that they will need to invest in creating better solar panels and batteries to capture solar energy, rather than wasting money trying to reproduce our star.
However, investors from IP Group Plc told Bloomerg's agency that although fusion energy takes longer than desired to be developed, many innovations have been made for this industry. they proved to be very profitable.
"Research companies patented many of their creations, from software that simulates plasma combustion of up to 150 million degrees Celsius to new types of magnets that have medical applications," Bloomberg reported.
Meanwhile, we must wait to find out whether Professor Hawking's wishes for unlimited and clean energy can be realized.
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