Subscribe options

Select your newsletters:


Please enter your email address:

@

News & Media

Latest ITER Newsline

  • Rendezvous | D and T to meet at JET in 2020

    In 2020, for the first time in more than 20 years, a reaction that only occurs in the core of the stars will be produced on Earth in a man-made machine. In the [...]

    Read more

  • On site | MOMENTUM believes in recent graduates

    It is rare for students to leave university and immediately begin work on a globally significant project. But thanks to the graduate program run by the project' [...]

    Read more

  • Tokamak Pit | Big steel elbow in place

    A cryostat feedthrough delivered by the Chinese Domestic Agency has become the first metal component of the machine to be installed in the Tokamak Pit, in an op [...]

    Read more

  • Neutral beam source | Europe awards EUR 20 million contract

    The contract, awarded to ALSYOM-SEIV (ALCEN group, France), launches the manufacturing phase for the beam source that will come on line in 2022 as part of the f [...]

    Read more

  • Image of the week | US Under Secretary of Science tours site

    Five months, almost to the day, after the US Secretary of Energy Rick Perry visited ITER, his deputy, Under Secretary for Science Paul Dabbar, stood by the same [...]

    Read more

Of Interest

See archived entries

1991: Fusion power is born

Phil Dooley, EFDA Public Information Office

Internal view of the JET vacuum vessel. Photo courtesy: EFDA/JET (Click to view larger version...)
Internal view of the JET vacuum vessel. Photo courtesy: EFDA/JET
Scientists are a careful and deliberate kind. They won't rush in; they like to be sure that everything is working before trying something new. Sometimes they will wait years, decades even, before finally allowing themselves to try the very thing that they have dedicated so much time and effort to.

The seventh of November, 1991, was such a day. After nearly four decades of research and preparation, the world would finally witness the first deuterium-tritium experiment at JET. Up to that time all fusion experiments had been conducted with a proxy: a deuterium-only (D-D) plasma—an almost identical gas, but easier to handle than radioactive tritium. D-D reactions, however, do not generate the power output of the real fuel.

But on this day, the practice runs were over. As they had done many times before, the operators turned the magnets up to 2.8 Tesla. They fired the discharge and created a stable H-mode plasma with current of 3 mega-amps. When they were sure that everything was stable, they opened the two neutral beam injectors that had been newly adapted for tritium and sent in a tiny shot of fuel, containing only 1 percent tritium.

Suddenly, theoretical fusion reaction became real. Neutrons flooded into the detectors, and were measured at a peak rate of nearly 1017 per second. The heating systems felt their load lifted as the hot helium nuclei began to buoy the plasma's energy levels. Power levels surged to levels high enough to run the surrounding villages, and then it was all over. In a mere second, decades of research and experimentation had culminated in success.

With these few short pulses, using less than a fifth of a gram of tritium, JET opened the door for future research. Aside from the production of 1.5 MW of power, the know-how for handling tritium and the measurement of its behaviour in a plasma gave the JET team the confidence to plan a full deuterium-tritium campaign for four years down the track, which ultimately set the world record for fusion power that still stands today.


return to the latest published articles