Global Scientists Begin Assembly of Crucial Solenoid for Fusion Reactor in France

Cadarache, France — Scientists from 30 countries, including India, have commenced the long-awaited assembly of the central solenoid, a vital component of the International Thermonuclear Experimental Reactor (ITER), the world’s most ambitious nuclear fusion project.

The solenoid, developed and rigorously tested in the United States, is central to the reactor’s ability to sustain and confine plasma — the ultra-hot fuel that powers fusion reactions.

Located in southern France, ITER aims to replicate the nuclear fusion process that fuels the sun. This groundbreaking initiative seeks to fuse deuterium and tritium — two isotopes of hydrogen — at temperatures exceeding 150 million degrees Celsius.

Unlike conventional nuclear fission, which splits atoms, fusion combines them, releasing immense energy without carbon emissions or long-lived radioactive waste.

At the heart of the ITER facility lies the tokamak, a doughnut-shaped chamber where fusion occurs. Inside, superheated plasma is suspended using powerful superconducting magnets to prevent it from touching the chamber walls.

The newly assembled central solenoid — often referred to as the “beating heart” of the tokamak — will be instrumental in achieving this magnetic confinement.

Once operational, the solenoid will generate a magnetic field strong enough to suspend plasma for 300 to 500 seconds. It is capable of storing 6.4 gigajoules of magnetic energy — equivalent to the energy released by a 1,500-ton train traveling at 160 km/h.

This will allow the plasma to reach the required temperatures and pressure for fusion to occur, paving the way for sustained energy production.

The ITER facility spans a 42-hectare site in Cadarache, making it one of the largest levelled scientific construction platforms in history.

The European Union is shouldering 45 percent of the construction costs, with other partners — including the United States, China, Japan, Russia, South Korea, and India — each contributing around 9.1 percent. India’s involvement includes significant components such as cryostat fabrication and in-kind equipment contributions.

Originally, the solenoid assembly was slated for 2021, but logistical and technical delays — exacerbated by the COVID-19 pandemic — pushed the timeline forward. Its assembly now marks a significant milestone in a project that has been decades in the making.

The broader objective of ITER is to demonstrate that nuclear fusion can be a viable and sustainable energy source for the future.

If successful, it could revolutionize how the world produces electricity — offering a clean, safe, and virtually limitless energy alternative amid rising concerns over climate change and fossil fuel dependency.

Meanwhile, private companies across the globe are racing to develop smaller-scale fusion technologies. However, ITER remains the world’s largest and most coordinated fusion experiment, embodying unparalleled international scientific collaboration.

With the solenoid’s assembly now underway, ITER moves one step closer to achieving its historic mission — to make fusion energy not just possible, but practical.

This article was created using automation technology and was thoroughly edited and fact-checked by one of our editorial staff members