Swiss Plasma Center trains researchers to harness the sun's energy
Holder of a recent PHD from the EPFL Swiss Plasma Center, Riccardo Agnello is now working for the nuclear fusion reactor ITER. The Swiss Plasma Center is making a major contribution to this enormous international project, which holds out great hope for clean, abundant energy without long-term radioactive waste.
While the assembly of ITER, the world’s largest nuclear fusion reactor, has started in the south of France, attracting widespread media attention, scientists are working on the next steps. Setting up the machine will require highly complex techniques, previously tested in various research centres. Riccardo Agnello works as a researcher on secondment from EPFL to Padua, northern Italy. The young doctor of physics trained at the Swiss Plasma Center is continuing his career in a consortium specialised in the development of a heating system for ITER. "Here, the timetable is tight, imposed by the entire fusion community. Research is progressing fast," says the young physicist. His hope, and that of everyone involved, is that nuclear fusion, the reaction at the heart of the sun and all the stars, will eventually be harnessed. It could provide mankind with almost infinite energy, without carbon emissions or long-lived radioactive waste.
ITER is an important step in this direction. This experimental reactor, 30 metres in diameter and 30 metres high, aims to prove the feasibility of fusion, which has so far been investigated in smaller machines. This poses many challenges. Among them are the methods of heating the plasma, a soup of ultra-hot particles that is essential for fusion. On Earth, the plasma must reach about 150 million degrees, ten times the temperature of the Sun, for fusion to produce energy. How can such a temperature be generated and maintained, and how can energy efficiency be optimised? This is where the work of Riccardo Agnello and his peers comes in.
In Padua, in a 17,500 m² building, there are two large machines known as "neutral beam injector” prototypes. They test heating systems for ITER's plasma, a field in which Riccardo Agnello is directly applying his skills. "As a physicist, I am in charge of developing, analysing and using data from these machines. For me, this is an opportunity on the one hand to continue my research, and on the other, to use all the experience I gained during my PhD thesis at the Swiss Plasma Center", he emphasises.
EPFL Swiss Plasma Center, an international reference
ITER represents one of the largest international scientific cooperation projects ever undertaken. The EPFL Swiss Plasma Center plays a key role in this project, as one of the world's top research laboratories on nuclear fusion. "We are directly linked to ITER by our research and also by our institutional role in training young scientists and engineers, some of whom will feed or reinforce ITER’s project teams, such as Riccardo," emphasises Ambrogio Fasoli, director of the centre. To do this, the EPFL laboratory has a key asset: its own tokamak, an experimental reactor called TCV, which is a miniature version of ITER. A pedigree that has earned its choice as one of the three national machines in Europe involved in the design of the giant international reactor.
Direct involvement in ITER
In its tokamak, the Swiss Plasma Center studies the best ways of heating the plasma, and of confining and holding it in place. The very hot and unstable "soup of particles" is kept away from the reactor walls by a magnetic field. The aim is to prevent the plasma from touching and damaging the walls, to keep it in its place while limiting the loss of energy. To meet this challenge, the Swiss Plasma Center is developing various techniques, including neutral beam injection and the injection of microwaves. These systems are used almost exactly as they will be in ITER. The EPFL laboratory is also developing algorithms that will improve ITER's real-time plasma control systems in the reactor. Finally, a research group at the Swiss Plasma Center based in Villigen, Canton Aargau, is testing superconducting magnets for the international reactor. These are key components of the machine, which generate the magnetic field to confine its plasma. "This is an important involvement on our part, which translates into a contract with ITER and brings significant financial support to our centre," says Ambrogio Fasoli.