‘Grandest scientific experiment’: World’s largest fusion reactor nears reality, seeks to replicate Sun’s energy

The International Thermonuclear Experimental Reactor (ITER), the world's biggest nuclear fusion experiment in Cadarache, France, has moved closer to completion after receiving the final shipment of required components to assemble the massive magnet at the heart of the reactor. The giant magnet is the central solenoid, designed and developed in the US at the Oak Ridge National Laboratory, and is one of the most important components of the massive experimental site. The experiment is jointly funded and operated in a coalition of China, the European Union (EU), South Korea, India, Japan, Russia, and the United States.

The central solenoid is awe-inspiring in its size as well as its efficiency. "The central solenoid is 18 meters (59 feet) tall and 4.25 meters (14 feet) wide, composed of six individual modules," Interesting Engineering reported earlier this week. "Each module weighs more than 122.5 tonnes (135 tons) and is wound from 6 kilometres (3.7 miles) of niobium-tin superconducting cable."

This is only one element of an extraordinarily vast system described as “the grandest scientific experiment in the world.” ITER’s tokamak, the doughnut-shaped machine built to contain plasma using extremely powerful magnets, stretches nearly a kilometre in length. At its centre lies the immensely powerful solenoid magnet, just one component of an even larger and more complex setup. "This component belongs to a magnetic system weighing 3,000 tonnes (3,300 tons) that interacts with nine vacuum vessel sectors," Interesting Engineering added.

15-year journey of ITER

The core system of ITER has taken 15 years to develop, with each module undergoing a two-year cycle of manufacturing and testing. Although ITER will not generate electricity for public use. It is regarded as one of the most important research efforts in the world that is aimed at unlocking commercial nuclear fusion, widely regarded as the holy grail of clean energy.

Nuclear fusion, the same process that powers the Sun, has the potential to provide virtually limitless clean energy on Earth. Unlike nuclear fission, it could deliver highly efficient, long-lasting energy without producing greenhouse gases or dangerous radioactive waste.

However, ITER’s enormous scale and ambitious objectives have resulted in delays and rising costs. Despite the successful delivery of the solenoid, the project remains years away from producing its first plasma, nearly two decades after construction began and with costs reaching around €22 billion.

ITER is still quite relevant, which may bring us invaluable scientific discoveries that would be impossible without its grand scale and funding. However, the megaproject is experiencing a rise in competition from smaller and more dexterous fusion ventures. Meanwhile, several other projects are on track to beat ITER to its mapped goalposts, and much more cost-free.