ITER fusion reactor reaches milestone as final vacuum vessel segment arrives in France

The ITER nuclear fusion project has reached a major milestone with the arrival of the final large component at its construction site in Saint-Paul-lès-Durance, France. The ninth and last segment of the massive vacuum vessel arrived on October 2, marking the completion of all primary components required for the reactor's core.

The vacuum vessel, which serves as the heart of the tokamak, is a donut-shaped stainless steel chamber designed to contain plasma at temperatures of approximately 150 million degrees Celsius. Once assembled, the vessel will measure 19.4 meters in diameter and weigh approximately 5,200 tons. The construction of these segments was a long-term international effort: Europe manufactured five segments, while South Korea provided the remaining four.

ITER Director Pietro Barabaschi stated that the arrival of this final segment allows the assembly process to proceed according to the updated schedule. While the core components are now on-site, the project still faces several years of assembly and installation. Research tests are currently projected to begin in 2034, with experiments using actual fusion fuel—a mixture of deuterium and tritium—expected to follow in 2039. The project aims to demonstrate that a fusion reaction can produce ten times more energy than is required to heat the plasma.