World’s Strongest Magnet

 World’s Strongest Magnet can lift an Aircraft carrier and Possibly power the future

The fusion reactor’s electromagnetic “heart” is complete, bringing us one step closer to clean, infinite energy, though there's still a long road ahead. The most powerful pulsed superconducting magnet system ever built is now complete, and will soon be part of the world’s grandest energy experiment. The world’s most powerful magnet, weighing a staggering 3,000 tons, can lift an entire aircraft carrier, six feet into the air. The International Thermonuclear Experimental Reactor (ITER) has reached a major milestone in the pursuit of clean energy. The system is the Central Solenoid of the International Thermonuclear Experimental Reactor (ITER), a towering magnet core built and tested in the US and destined for southern France, where the international project is assembling its gigantic tokamak. The magnet system will serve as the electromagnetic “heart” of the reactor, strong enough, according to ITER, to lift a freaking aircraft carrier.

The world’s largest superconducting electromagnet system is now complete, promising to propel the ITER project into the next phase of fusion energy research. According to Interesting Engineering, The ITER project, located in Southern France, is an international collaboration which aims to prove the scientific and technological feasibility of harnessing fusion power. Recently, the project announced the successful completion of its pulsed superconducting electromagnet system. For the uninitiated: Tokamaks are doughnut-shaped vessels which contain superheated plasma for nuclear fusion, the energetic reaction which powers stars like our Sun. Tokamaks constrain the plasma by generating very strong magnetic fields, hence the importance of ITER’s Central Solenoid. This system, which is the largest and most powerful ever assembled, is integral to the ITER Tokamak, the device designed to produce controlled fusion reactions. “What makes ITER unique is not only its technical complexity but the framework of international cooperation that has sustained it through changing political landscapes,” ITER Director-General Pietro Barabaschi noted.

ITER is dedicated to validating nuclear fusion as a viable energy source, though none of the reactor’s output will be used to power anything. ITER is simply a gigantic and expensive technology demonstrator, one that’s inching increasingly closer to actually flipping the “on” switch to recreate the power of the Sun here on Earth. It’s an expansive collaboration involving over 30 countries, aiming to prove that fusion energy, basically, slamming atoms together until they produce different atoms, releasing massive amounts of energy in the process, can be harnessed and scaled into a commercially viable and essentially limitless power source. At the core of this electromagnetic system is the Central Solenoid, a powerful magnet which has been built and rigorously tested in the US before being shipped to the ITER site. This 3,000-ton component is a crucial part of ITER’s fusion reactor, helping to initiate and confine the superheated plasma.

The newly completed magnet system isn’t going to work alone. The Central Solenoid joins six massive ring-shaped Poloidal Field magnets built and delivered from Europe, China and Russia, forming a 3,000-ton (2,721 tonne) system of superconductors cooled to -452.2 degrees Fahrenheit (-269 degrees Celsius). Together, the super cooled magnets will trap and shape scorching plasma at 270 million degrees Fahrenheit (50 million degrees C), ten times hotter than the Sun’s core, until atomic nuclei fuse and let out a tenfold energy return. As explained by the ITER project, once fully assembled, this pulsed magnet system will have an immense weight of 3,000 tons and “will work in tandem with six ring-shaped Poloidal Field magnets, built and delivered by Russia, Europe, and China.” Fusion energy works by mimicking the processes occurring in the sun. In ITER’s Tokamak, hydrogen isotopes, deuterium and tritium, are injected into the chamber. The electromagnet system then sends a current through the gases, transforming them into plasma. The powerful magnets then confine and shape the plasma, keeping it from touching the reactor’s walls. The plasma is then heated to an incredible 150 million degrees Celsius, ten times hotter than the sun’s core.

At these extreme temperatures, atomic nuclei fuse, releasing vast amounts of energy. “At this temperature, the atomic nuclei of plasma particles combine and fuse, releasing massive heat energy,” ITER stated. Commercially viable fusion has long been the clean energy grail, and ITER’s setup is expected to generate 500 megawatts of energy from just 50 megawatts of input. That kind of power return would mark the start of self-sustaining “burning plasma”, though there’s a long road to reach the goal. Private companies are attempting to demonstrate smaller-scale tokamak designs as a potential way to realize the future of fusion, though neither approach has had its breakthrough moment to date. ITER’s ultimate goal is to demonstrate that fusion can be a practical source of energy. Once fully operational, the project is projected to produce 500 megawatts of fusion power from just 50 megawatts of input heating power, achieving a tenfold energy gain. This self-heating reaction is expected to create what is known as a “burning plasma.” ITER’s design and its projected efficiency represent a major leap forward in the quest for clean, sustainable energy. As ITER explained, “At this efficiency level, the fusion reaction largely self-heats, becoming a ‘burning plasma.’”

In 2022, the US Department of Energy and Lawrence Livermore National Laboratory announced net energy gain in a fusion reaction at the National Ignition Facility, but even that high-water-mark did not account for “wall power” used in the experiment, making it another incremental step in the marathon towards viable fusion power, rather than a shortcut to the finish line. ITER isn’t just a physics experiment, it’s a geopolitical flex. Despite tensions between member countries, the project has delivered on component construction and hit its 2024 construction targets. (The collaboration also launched a private sector fusion project last year for sharing data and furthering the project’s R&D goals). The ITER project is a testament to the power of global cooperation. More than 30 countries have contributed to the project, each playing a key role in the assembly of the Tokamak and its components. The US, for instance, is responsible for the Central Solenoid, while Russia, China, and Europe have contributed Poloidal Field magnets. Japan and Korea have provided crucial components such as the vacuum vessel and thermal shields. Together, these nations are working toward the common goal of proving that fusion power can be a reality. “With ITER, we show that a sustainable energy future and a peaceful path forward are possible,” said Pietro Barabaschi, ITER’s Director-General, in a collaboration release. Of course, ITER has yet to realize the “sustainable energy future” part of its project, so don’t hold your breath for the peaceful future, either. Now in its assembly phase, ITER is building up steam towards its actual goals, a slight increase in momentum from the collaboration’s plodding steps in producing its constituent parts. If it works, this magnetized machine could be a watershed moment towards a carbon-free energy future, even if it does not contribute to the power grid itself.