The nuclear fusion of ITER, one of the most beautiful projects of humanity

Can you imagine a world in which energy is totally clean and affordable? It is very likely that you live in that same world, but about five decades away. ITER is a project that involves a good part of humanity and pursues the dream of clean and free energy. All thanks to nuclear fusion.

Although "nuclear" has pejorative connotations inherited from the last century, experts say fusion will be the sustainable energy of the future. Along with international projects such as the International Space Station (ISS) or Square Kilometer Array (SKA), ITER is one of those remarkable and beautiful companies that unite us all. The kind of initiatives that love science.

When we talk about nuclear fusion, we often confuse it with nuclear fission. Both are chemical processes that release large amounts of energy, but their operation is totally different. Its consequences too.

Fission consists of dividing a heavy nucleus into two smaller ones. As a result, radioactive waste of various types appear. Nuclear fusion has nothing to do with that, but with a reverse chemical 'operation'. By joining two very light atomic nuclei they form a heavier stable nucleus and release energy.

This energy is clean, and in fact it is the mechanism that the Sun uses to generate light. This sunlight is nothing but photons that reach our planet. A nuclear fusion reactor, or Tokamak, an acronym for the Russian "toroidal chamber with magnetic coils", copies this solar mechanism to generate electrical energy from the plasma.

HOW WILL THE ITER REACTOR WORK?

In the Sun, fusion reactions take place in its core, and not in the mantle or crown. In fact, it takes a great pressure and temperature to compress the hydrogen nuclei against each other, forming helium and releasing energy. Formally, the most efficient reaction is that between two isotopes of hydrogen, deuterium and tritium, although these are technicalities.

We can call it simply "plasma". Although on Earth we have all the elements to form this fourth state of matter, there are no natural conditions of pressure and temperature. Neither inside a volcano, in case the reader has a doubt. With the Tokamak (below we see the JET of 1997), we seek to achieve similar conditions for the solar plasma and thus achieve a stable reaction that releases energy.

A Tokamak is a structure in the form of a toroid (a donut, the yellow zone in the diagram above) through which the plasma moves at high speed. This plasma is enclosed within a ceramic vessel, but it is not this that presses to contain it. They are great magnetic fields that imprison the particles in an invisible structure called "magnetic confinement".

Good part of the technology to accelerate these particles comes from the LHC, and another so much is more known by the general public. The plasma of protons, deuterium and tritium, when compressed, emits enormous amounts of heat. With this energy steam is heated, and this is transferred through a turbine. This latest technology is used in a multitude of power plants, from thermoelectric to nuclear.

ITER, ONE OF THE MOST BEAUTIFUL PROJECTS OF HUMANITY

Throughout our history we have achieved enormous milestones when we have used science for common goals. The Large Hadron Collider (LHC), the Gravitational Wave Detection Observatory (LIGO), the International Space Station (ISS), the Super-Kamiokande or the Square Kilometer Array (SKA) are some of the most talked about examples. ITER is part of them, a project in which 35 countries directly participate.

These types of associations, which promote scientific and technological development as well as collaboration between countries, also make possible the exchange of ideas and mutual learning. By itself, it is already remarkable the fact that 35 nations have agreed to finance this type of prototypes (ITER is that). Of course, the size of the project makes it impossible for a single nation to carry it out.

But it is even more interesting that the International Thermonuclear Experimental Reactor pursues the ultimate goal of generating clean energy, and that it does so in the very long term. Once built it will be the largest Tokamak in the world. This will not be for quite some time. The assembly phase is starting and the reactor will not start up until 2024.

The first plasma will be introduced a year later, but it will not be until 2035 when the merger operation starts. In addition, this reaction will not be profitable. That is, the reactor will consume more energy than it will generate. As an energy source it does not seem very smart, but there is a lot of work ahead. A lot of checks and measurements. Of gradual improvements and iterations.

There are currently 2,000 people working directly in purely civil engineering work. That's the size of the project, not counting physicists, chemists, managers, diplomats, manufacturers and several dozen more direct jobs. More indirect ones And they do everything for and for future generations.

THE CLEAN ENERGY OF THE FUTURE NEEDS PRESENT ACTIONS

We have mentioned the long term, but let's put another calendar ahead to see it in perspective. In 2035 the first tests with plasma will be made. In 1995, JET, the precursor project of ITER, managed to generate an electric power of 16 MW, while its older cousin seeks to generate 500 MW. Even so, ITER is purely experimental. It will not be used as an energy center.

For something like that, we have to travel much more to the future, to 2050, when the ITER tests have gone well and the first commercial plant has been built. By then, at least 139 countries will use only renewable energy. The exploitation of ITER, if everything goes well, could be a fact in 2060 or 2070. Although it is unlikely that everything goes according to the calendar, which already has decades of delays. The last one in 2017 with Trump.

To situate ourselves, the origin of nuclear fusion centers goes back to Gorbachev and Reagan. It will be the children or grandchildren of the project engineers who will benefit from its results. It is likely that children will be born on Mars before we have been able to stabilize the reaction within the following Tokamak reactors.

Or, put another way, it is unlikely that the people who work in the ITER project will see its final results. The clean energy of the future needs present actions. That today there are professionals dedicating their lives to this type of projects makes it one of the most beautiful of humanity. One that we do between all and for all.

The race to take advantage of nuclear fusion would get its first fruits in a decade

Hotter than the center of the Sun was the plasma (an electrically charged gas) obtained by the private Tokamak Energy last month in England. He achieved this by heating hydrogen to a temperature of 15 million degrees inside an experimental reactor.

It was one more step in the race to tame an artificial mini-auction to get its energy milked. The concept behind is known as nuclear fusion and, unlike nuclear fission - which derives energy by pulverizing atoms and generating waste that remains for decades - here what is achieved with high temperature is to unite the nuclei of two atoms to form one different, which means releasing heat, as it happens inside the Sun. Its raw material (hydrogen) is cheap and the radioactive waste lasts less time.

The British project wants to take advantage of ITER, the experimental mega-reactor that has been building, for a decade, an international consortium led by the European Union in Cadarache, in the middle of the French countryside. The ITER will be completed in 2025, when it is expected to generate its first plasma, but it is estimated that only in 10 more years it would be able to produce energy efficiently.

A similar path in terms of deadlines follows 10 national research programs in the United States, Korea, China and the United Kingdom, each with a budget of around 100 million dollars and which, to a greater or lesser degree, have already achieved their goals. small artificial suns and even generate energy, but tiny.

But as it seems to happen in the space race to Mars, the private could advance in several years. Counting Tokamak Energy, at least 20 private companies are developing their own projects in a reserved way and only know about them when they obtain favorable results. "This does not mean that what they do is not of quality, only that we do not have enough information to know it," acknowledges the physicist of the U. de Chile Leopoldo Soto.

While mergers have been achieved experimentally for more than 50 years, another thing is that they are long enough in time to take advantage, recognizes Soto. For that it is necessary to get temperatures close to 100 million degrees, 10 times that of the Sun's core. At that temperature, the plasma would be stable enough, so that a sufficient amount of nuclear reactions can be produced that result in an amount of energy greater than injected.

At Tokamak Energy they say they could get a plasma of 100 million degrees as early as next year. If that goal is met, the company plans to produce energy on an industrial scale by 2025, when ITER will just start its experiments, which would be a major blow for the international consortium. "Our goal is to make fusion energy a commercial reality by 2030," says Jonathan Carling, CEO of Tokamak Energy.

But it is not enough to reach high temperatures. Another obstacle to a stable fusion is that there are still no materials that resist the damage to which the walls of the experiment will be subjected by containing the plasma from which the artificial sun is formed, says Soto, who in the Chilean Nuclear Commission has successfully developed mergers at a minimum scale.

For the plasma to be tamed, one of the options is to be contained within a kind of magnetic prison.

In the case of ITER, the first of the 18 magnets that will form this shield is already built. To get an idea of ​​the dimensions of the experiment, each magnet measures the equivalent of a four-story building and weighs more than a Boeing 747. The plasma is confined to the shape of a picard, but transfers its heat to the walls. The longer the content, the more efficient the process will be and the less damage the reactor will cause.