Japan’s joint fusion reactor project with the European Union (EU), the JT-60SA, has been inaugurated, marking the start of experimental operations for the world’s biggest and most advanced tokamak.
The high temperatures inside the reactor could be enough to force the hydrogen particles to overcome their natural electromagnetic resistance, and fuse together to create helium – releasing energy in the form of light and heat. It’s a process that mimics the inner workings of the Sun.
Many – from scientists to climate change activists to energy industry professionals – have pinned hopes on using this process to fuel the world, as it is hoped to generate more energy than goes into producing it. Unlike nuclear fission, which splits atoms rather than fusing them, and produces dangerous waste products, fusion is considered clean.
When gaseous fuel is introduced into the chamber, magnetic coils cause it to accelerate to very high speed, at which point the gas is ionized and becomes plasma.The plasma is then heated to extraordinarily high temperatures (up to 300 million degrees Celsius) which is another reason for the magnetic coils – only powerful magnetic fields can contain plasma that hot.
Construction has been ongoing since 2013, with commencement delayed by a 2011 earthquake that saw a planned 2016 debut pushed back.
“The generation of fusion energy does not produce carbon dioxide – making it an important technology in the path to net zero emissions. The fusion reaction is intrinsically safe: it stops when the fuel supply or power source is shut down. It generates no high-level long-lived radioactive waste,” explained the European Commission’s directorate-general for Energy.
The JT-60SA is one of three fusion-related devices the EU and Japan are collaborating on, which complement the pair’s work on the International Thermonuclear Experimental Reactor (ITER) project.
Meanwhile, ITER’s main reactor and first plasma are scheduled for 2025. ITER, still under construction in France, will build on the knowledge scientists glean from tests on the JT-60SA. The six-storey tall JT-60SA is about half the planned height of ITER, but its plasmas are expected to closely resemble those produced by its successor.