What is the Joint European Torus (JET)?

We’re here to talk about a machine that was very, very large, very successful, and one of the hottest places on Earth when it was at its peak.

What is JET? It is the Joint European Torus. JET is a European project that was based at Cullum Campus in Oxfordshire in the UK.

JET was originally conceived in the 1970s with construction beginning in 1979 and its first plasma in 1983. It was only going to run for a few years before being replaced by the next generation machine. It actually ran for 40 years with it finally finishing at the end of 2023.

JET had many firsts in its lifetime. One of its pinnacles was the first time that tritium was used in any fusion experiment. JET held the fusion power and energy record from 1997, taking it from the experiment TFTR in America. It held that record and broke it in 2021 and 2023.

Decommissioning JET will teach us a lot about the methods and the ways that we will do decommissioning not just for JET but for future concepts as they come along. This experience and the lessons we learned from JET have fed into projects like ITER, STEP and many more beyond that exist around the world today.

Fusion would not be where it is today without JET’s experience and its legacy. It taught us so much while it was operating and it will continue to tell us more as we move from where we are today towards fusion energy on the grid.

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