The world's largest and most advanced tokamak fusion reactor has gone online as the EU/Japanese 370-tonne JT-60SA reactor was fired up for the first time during an inauguration ceremony in Ibaraki Prefecture, Japan.
First conceived by Soviet scientists in the 1950s, tokamaks are toroidal reactors that are one of the leading contenders to become the first commercially viable fusion power plants. The name is a Russian acronym for Toroidal Chamber with Magnetic Coils and consists of a large doughnut-shaped chamber surrounded by magnetic coils that compress a plasma made of hydrogen isotopes until it reaches pressures and temperatures that are only found in the interior of the Sun to initiate fusion.
In concept, it's a simple machine and achieving fusion is relatively easy, but in practice it's extremely difficult to build a reactor that can maintain a sustained fusion reaction that generates more power than is fed into it. The Japan Torus-60 (JT-60) project has been running since 1970 and the JT-60SA is that latest and biggest iteration.
The JT-60SA is currently a joint project by the EU and Japan, with participation by Britain, which signed a separate agreement after leaving the Union. The original reactor was upgraded several times as technology evolved, resulting in a complete disassembly and reassembly in 2013, with work finishing in 2020. Unfortunately, this was followed by a massive electrical short in 2021 that necessitated two years of repairs.
The initiation of operations for JT-60SA was inaugurated on December 1, 2023 by the EU’s Commissioner for Energy Kadri Simson and Japan’s Minister of Education, Culture, Sports, Science and Technology (MEXT) Masahito Moriyama in a formal ceremony. Though the upgraded reactor still isn't anywhere near to being a practical power generator, it will be used to overcome many outstanding problems as well as testing materials and procedures that will be needed for commercial stations.
For 75 years we've been told that fusion power was only 25 years away and billions of dollars have been spent to make it practical. However, since successful fusion power would provide humanity with unlimited clean power forever, a little patience might be in order.
The video below shows the upgrade of the JT-60SA.
Source: European Commission
