Controlled nuclear fusion – a clean, near-perpetual source of energy – would revolutionize the world. In recent years, significant steps on the path to a fully operational, efficient fusion reactor have been made, and this week another milestone has been reached: German engineers from the Max Planck Institute have successfully fired up their nuclear fusion reactor, announcing that they have managed to suspend plasma for the first time.
Their 16-meter-long (52-foot-long) experimental fusion reactor, Wendelstein 7-X (W7X), is one of the largest in the world. It took 19 years and €1 billion ($1.1 billion/£715 million) to complete, and contains over 425 tonnes (470 tons) of superconducting magnets, all of which need to be cooled to absolute zero. Within it, the process that operates at the heart of stars can hypothetically take place.