Reflections, and outlooks, many conversations between people who have known each other for 20 or more years. Among them young scientists just starting their career: that was the celebration of the 25th anniversary of JET’s first plasma.

The 25th Anniversary celebration on that sunny day brought together over 130 people with diverse backgrounds and ages: engineers, physicists, students, postgraduates, retired staff, and three of the five directors, all of whom had made Europe’s largest fusion device such a successful world-class experiment. After lunch, former Director Paul-Henri Rebut reflected on the design and realisation of the machine which, in his own words, were guided by two core principles: “simplicity and sturdiness”. These features made JET, right from the start, flexible and able to evolve its hardware with the changing requirements imposed by the new areas of physics and technology investigations. Rebut’s lively talk enlightened much on what happened on day-one. Afterwards, the current director, Francesco Romanelli, in his engaged talk focused on the future of JET and pointed out Europe continues to invest in the machine.

A promising start

The 25 June 1983 was an exciting day for all of those involved. It became even more so since the press where also present: journalists were allowed to experience the very first steps in the coming to life of the experiment. It was already a big success. The preceding five years of frantic construction had made it possible for the JET Team to start, on that day full of suspense and expectation, the process which opened the way for a string of achievements and enhancements. Two examples illustrate the milestones set by JET in International Fusion Research: In 1991 the first ever controlled release of fusion power using deuterium-tritium as a fuel mixture took place in a Tokamak. Newly two million watts of fusion power were produced. Six years later the world record in fusion power production was set when 16 million watts were produced.

JET – an Investment for ITER

JET main assets include its large size, its magnetic configuration similar to ITER, its beryllium, tritium and remote handling capabilities. These features make JET the machine closest to ITER. Today, JET continues to play a major role in supporting ITER construction and operation. JET will test the same combination of materials for plasma facing components as in ITER, thereby providing valuable operational experience. Therefore investing on JET today in making it as close as possible to ITER clearly represents future savings on ITER operational costs and time.