All manufactured components for the ITER Central Solenoid, a massive pulsed electromagnet at the core of the fusion device, are now complete. This marks a significant construction milestone for the international project. The Central Solenoid's primary function is to induce a powerful current in the ITER plasma, a necessary step for initiating, shaping, and sustaining the fusion reaction. The system consists of six individual modules, which will be stacked to form a single cylindrical magnet. Its completion represents a major de-risking step for the machine's assembly and future operational campaigns, relying on a complex international supply chain to deliver the finished parts to the construction site in France. Source: ITER

The technical specifications of the Central Solenoid underscore its scale and power. When fully assembled, the magnet will stand 18 meters tall, measure 4.3 meters in diameter, and weigh 1,000 tonnes. It is designed to generate a peak magnetic field of 13 Tesla and drive up to 15 million amperes of current within the plasma. The system's magnetic energy storage capacity is 5.5 gigajoules, sufficient to lift an aircraft carrier two meters. To achieve these parameters, the magnet windings are fabricated from niobium-tin (Nb3Sn) superconducting cables, which must be cooled to cryogenic temperatures to operate without electrical resistance. Source: ITER

The technical specifications of the Central Solenoid underscore its scale and power.

Completion of the Central Solenoid is the result of a multi-year international collaboration. The United States was responsible for designing and manufacturing the six main modules, with production managed by General Atomics in California. Other essential components, including the support structures, busbars, and cryostat systems, were contributed by ITER partners in China, Europe, and Russia. The final module arrived at the ITER site in southern France, joining the five previously delivered modules. The next phase involves the intricate process of stacking and connecting these modules inside the main tokamak pit, a precision engineering task critical for the device's magnetic confinement performance. Source: ITER

As the central pillar of the ITER magnet system, the Central Solenoid functions as the primary transformer winding in the tokamak. By rapidly changing the current flowing through its superconducting coils, it induces a powerful electric field inside the vacuum vessel. This field ionizes the deuterium-tritium gas and drives the initial plasma current. The pulsed nature of the solenoid is essential for this plasma initiation phase. Following startup, the solenoid will continue to provide inductive current drive and control plasma shape and stability throughout the operational pulse, working in concert with the toroidal and poloidal field coils to confine the superheated plasma and enable the conditions for fusion science. Source: ITER