The first of six superconducting magnet modules for the International Thermonuclear Experimental Reactor (ITER) central solenoid left the General Atomics facility in the US earlier this month for the ITER site in France, according to an ITER (also signifies “The Way” in Latin) statement.
The central solenoid is at the heart of the ITER “tokamak” (derived from the Russian words for toroidal magnetic confinement). The tokamak, which will produce thermonuclear fusion power, relies on the magnet to propel and shape its plasma stream. It initiates plasma current, as well as drives and shapes the plasma during operation.
The machine assembly of the ITER, or the world’s largest nuclear fusion project, started in Cadarache, France, in July last year. The ITER machine is being assembled to replicate the fusion power of the sun, to enable generation of clean unlimited energy, and the first ultra-hot plasma is expected to be generated in late 2025. The world’s largest science project is intended to demonstrate that fusion power can be generated on a commercial scale.
ITER is a partnership composed of the European Union, the UK, Switzerland, China, India, Japan, Korea, Russia and the US. Each partner contributes in-kind hardware to support their share of project construction while sharing all of the science and technology.
The largest of ITER’s magnets, the central solenoid will be made up of six modules. Fully assembled, it will be 18 meters tall, 4.25 meters wide, and will weigh 1,000 tonnes. The Central Solenoid is so powerful that its magnetic force “is strong enough to lift an aircraft carrier 2 meters (6 feet) into the air. At its core, it will reach a magnetic field strength of 13 Tesla, about 280,000 times stronger than the earth’s magnetic field “, an ITER statement said.
ITER’s realising of a self-heating plasma is expected to generate 10 times more heat than is put in. Fusion provides clean, reliable energy without carbon emissions, with minute amounts of fuel and no physical possibility of an accident with meltdown. The fuel for fusion is found in seawater and lithium, while it is abundant enough to supply the world for millions of years. A football-sized amount of this fuel is equivalent to around 10,000 tons of coal.
Millions of components from all over the world will be used to assemble the giant reactor, which will weigh 23,000 tonnes. It is a concrete demonstration of the willingness of ITER’s 35 partner countries to join together in an enduring way in their common fight against climate change and for access to limitless clean energy.
ITER Director General Bernard Bigot highlighted the extensive progress in manufacturing and construction, which is now around 60 percent completed, with the first experiments scheduled by 2025. ITER is expected to produce 500 MW of fusion power by the late 2030s. “The ITER project is the most complex scientific collaboration in history. Very challenging first-of-a-kind components are being manufactured on three continents over a nearly 10-year period by leading companies such as General Atomics. Without this global participation, ITER would not have been possible; but as a combined effort, each team leverages its investment by what it learns from the others”, Bigot said.
At the International Atomic Energy Agency (IAEA) General Conference on fusion energy research last month, Bigot said: “When we prove that fusion is a viable energy source, it will eventually replace burning fossil fuels, which are non-renewable and non-sustainable. Our mission is to provide a new option which is safe, sustainable and economically competitive. Fusion will be complementary with wind, solar and other renewable energies”.
According to Bigot, “fusion has the potential to provide safe, environmentally friendly energy as a realistic replacement for fossil fuels during this century. With a nearly unlimited global supply of fuel, it also has the potential — in complement with renewable energies — to transform the geopolitics of energy supply. I can think of no better illustration of that transformative action than the ITER project, where our US partners work in close collaboration with contributors from China, Europe, India, Japan, South Korea and Russia, as a single team dedicated to achieving the common goal of a bright energy future.”
Creating the magnetic fields in a tokamak requires three different groups of magnets. External coils around the ring of the tokamak produce the toroidal magnetic field, confining the plasma inside the vessel, while the poloidal coils that orbit the tokamak control the position and shape of the plasma. Instead, the central solenoid in the center of the tokamak uses a pulse of energy to generate a powerful toroidal current in the plasma that flows around the torus. The movement of ions with this current, in turn, creates a second poloidal magnetic field that improves the confinement of the plasma, as well as generating heat for fusion.
General Atomics has only begun shipping the first of six total modules that will comprise the central solenoid. Each one weighs 110 tonnes and ITER will stack and link them together at the center of the reactor in France.
