Donuts, bottles and magnets to talk about how to get electric energy out of the process of nuclear fusion, the same process that powers the sun. In a future reactor a gas made of hydrogen isotopes (deuterium and tritium) will be heated at very high temperatures becoming a plasma. A very special container, made of stainless steel and magnetic fields, is needed to contain this plasma. In the first experiments in the Sixties, the magnetic fields were bottle-shaped, with two magnetic bottlenecks at the extremes. However, they were not able to contain all the particles: many of them scaped from the extremities and the plasma was not able to reach performances good enough. Scientists thought of changing the geometry of the plasma container from straight to circular. The outcome was a toroidal container: a sort of hi-tech donut filled with magnetic field that is able to contain the hot plasma. 

Project manager: Francesco Suman Shooting and editing by Elisa Speronello