Scientists from multiple nations are constructing the International Thermonuclear Experimental Reactor in southern France to test fusion energy at an unprecedented scale. The project carries an estimated cost of $22 billion and aims to replicate conditions inside the Sun.
The facility features a doughnut-shaped vacuum chamber designed to contain plasma at 150 million degrees Celsius. Engineers must manage extreme temperatures by placing superconducting magnets near absolute zero, separated only by a thin heat shield. Cracks discovered in the heat shield piping in 2020, along with welding issues and pandemic disruptions, added years to the schedule and $5 billion in costs.
