Magnetic confinement fusion: energy that imitates the stars

A safe, sustainable and inexhaustible source of energy, a possible turning point in the decarbonization process we are supporting.

The technology

Fusing two hydrogen nuclei releases a huge burst of energy – in nature, this is the type of physical reaction that powers the sun and the other stars. The great advantage of the technology is that it does not emit greenhouse gases; nor does it emit heavily polluting or highly radioactive substances, which makes it a highly attractive energy source. It is also virtually inexhaustible as it uses a blend of easily obtainable elements as fuel: deuterium and tritium, two hydrogen isotopes. Deuterium comes from seawater, while tritium can be produced by a physical reaction with lithium.

Magnetic confinement technology is being investigated as a potential means of achieving fusion continuity control in power plants. As its name suggests, the technology uses extremely powerful magnetic fields to control the plasma in which the fusion takes place. The journey towards this technological revolution will be a long one, but will lead to a more sustainable future. This is why we are focusing on magnetic confinement fusion and why we are collaborating with leading public and private research bodies to develop it. We see it as a turning point in the decarbonization process.

When we get fusion to a mature enough point that it can be used in industry, the stage will be set for unprecedented things. We will finally have a widespread supply of clean, safe, sustainable energy. Power stations fed by fusion reactors could meet the growing demand for energy at big production and population centres while maintaining high sustainability. Smaller stations, on the other hand, integrated with renewable sources, could make it easier to provide energy to small communities and off-grid businesses.

The technical challenge

Fusion takes place when two nuclei from hydrogen isotopes come so close as to join and form a new, heaver element, such as helium. Hydrogen is used in the form of two isotopes: deuterium and tritium. The nuclei of the two isotopes, in addition to a proton, have one and two neutrons respectively. The sun instead uses a single-proton hydrogen isotope, protium, by far the most abundant in the Universe (99.98%).

Whatever kind of isotope the process begins with, two hydrogen atoms have the same charge, meaning they tend to repel each other electrostatically. That means temperatures of hundreds of millions of degrees are needed to fuse them together. Thermal agitation enables fusion to take place inside a gas ionised at a very high temperature called plasma.  The main technical difficulty to solve involves managing the plasma, which must be confined in a high vacuum, within a limited space and, given its very high temperature, without coming into contact with the machine’s surfaces. This is accomplished by using a tokamak, a doughnut-shaped device (toroid) device which, through an extremely powerful magnetic field generated by super magnets placed around the chamber, creates plasma at extremely high temperature and swirls it around the toroidal chamber without allowing it to come into contact with the walls. This is where the name magnetic confinement fusion comes from. “Turning on” a fusion reactor involves inserting a blend of deuterium and tritium into the tokamak, heating it to a plasma state and then, by increasing the temperature further, bringing it to the point where fusion can take place. The fusion process releases highly energetic neutrons, which are soaked up in a “blanket”: this is a thick coating that contains the fusion chamber.

The global picture and Eni's partnerships

Studying, designing and building machines capable of managing physical reactions similar to those that take place at the core of stars is the technological goal that the greatest minds in the world of energy research are working towards. We know the strategic importance of being part of this challenge. That’s why we are part of the development of the most significant Italian and international projects in the area of magnetic confinement fusion research:

The goal the whole world is working on is to build the first fusion power plant capable of feeding climate-neutral electricity into the grid. CFS plans to have the first SPARC pilot reactor in operation in 2025.

Industrial integration

Developing magnetic confinement fusion is a global challenge that involves a wide range of international talent in industrial science and technology. Everyone will have to put their skills and experience to use at the service of this revolutionary technology. At Eni, besides working with major research bodies, we have made our HPC5 supercomputer available to researchers, who will use its great calculating power for highly complex mathematical models that will describe the physics of plasma and simulate its behaviour.