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Central Solenoid

The US is responsible for 100% of the central solenoid (CS) magnet, including design, R&D, fabrication of 7 CS modules using supplied conductor (from Japan), associated structure, assembly tooling, bus extensions, and cooling connections.

The center solenoid is at the heart of the ITER tokamak.
The central solenoid is at the heart of the ITER tokamak. It both initiates plasma current and drives and shapes the plasma during operation. Image: US ITER

The central solenoid serves as the backbone of the ITER magnet system. The CS induces the majority of the magnetic flux change needed to initiate the plasma, generate the plasma current, and maintain this current during the burn time. The CS is made of six independent coil packs that use a niobium-tin (Nb3Sn) cable-in-conduit superconducting conductor, held together by a vertical pre-compression structure. The conductor will be produced in unit lengths up to 910 m. The US is responsible for the 6 modules of the CS, a spare module, and the structure that ties them together and links these modules to the rest of the magnet system.

How are we building one of the world's largest superconducting electromagnets for ITER? Watch Building the Heart of ITER.


For more information, contact Kyle Wooley, Central Solenoid Team Leader, US ITER Project Office, Oak Ridge National Laboratory | | 865-241-4329.

Fact Sheet

central solenoid assembly

Central Solenoid Module Assembly Underway

Two central solenoid modules are now in the Assembly Hall for assembly preparation.

ITER tokamak showing magnetic fields

New Animation Brings Central Solenoid to Life

Watch how invisible forces generated by the "heart of ITER" will help make fusion happen.

Central solenoid module at ITER

CS tests and verifications prior to assembly

In January next year, the "most powerful magnet in the world" will begin taking shape. The first module of the Tokamak's central solenoid will be positioned on a bespoke platform and the assembly process will begin in the ITER Assembly Hall. One by one, the six modules that make up the 18-metre tall, 1,000-tonne component will be stacked one upon the other and held together by a sets of tie plates (18 exterior and 9 interior).

Source: ITER Newsline

ITER staff in front of central solenoid module

US ITER wraps up a year of technical achievements and record contracts

Despite the pandemic, US ITER made great strides over the past year.

One module in packaging; one module ready to package

First-of-a kind superconducting magnet en route to ITER site

The first of six superconducting magnet modules for the ITER central solenoid left General Atomics’ Magnet Technologies Center in Poway, California for the ITER site in France. The second module will depart later this summer. The international ITER fusion facility under construction in France has already begun initial tokamak assembly activities; the central solenoid is expected to be installed in 2023.

CS piping

Strong bonds: MPEX magnet system benefits from US ITER expertise

As Oak Ridge National Laboratory’s Material Plasma Exposure eXperiment (MPEX) prepares for the start of fabrication, ORNL’s Phil Ferguson credits US ITER staff for sharing hard-earned expertise to help jump-start the design of the MPEX superconducting magnet system.