Subscribe options

Select your newsletters:

Please enter your email address:

@

News & Media

Latest ITER Newsline

  • Component delivery| A jewel in a box

    Sailing under the flag of Germany, the Regine is a mighty ship, strengthened for heavy cargo and equipped on its portside with two 750-tonne on-board cranes. Ha [...]

    Read more

  • Education | Make your own tokamak with 3D printing!

    It's not Lego, but it is definitely 'hands-on.' To offer a tangible device to illustrate the workings of magnetic confinement fusion in a tokamak, the ITER Orga [...]

    Read more

  • Worksite | Europe's Fusion for Energy is building the ITER installation

    Anyone driving to ITER can take full measure of the enormity of the project a few kilometers before reaching the destination. Gigantic cranes can be seen from a [...]

    Read more

  • Disruption mitigation | Experts in plasma disruptions gather online

    On 20-23 July, 120 international experts participated in the 1st IAEA Technical Meeting on Plasma Disruptions and their Mitigation, jointly organized by the Int [...]

    Read more

  • Start of assembly | World dignitaries celebrate a collaborative achievement

    Due to the constraints imposed by the COVID-19 pandemic, the crowd in the ITER Assembly Hall was small. But thanks to live broadcasting and video feed, the audi [...]

    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