Scientists in Germany are poised to conduct a nuclear fusion experiment they hope will advance the quest for a clean and safe form of nuclear power.
The nuclear fusion research centre at the Max Planck Institute in Greifswald. Photograph: Stefan Sauer/AP
In a test expected to be attended by Angela Merkel, the chancellor, researchers will inject a tiny amount of hydrogen into a special device and heat it until it becomes a super-hot gas known as plasma – mimicking conditions inside the sun.
The experiment at the Max Planck Institute in Greifswald, north-east Germany, is part of a worldwide effort to harness nuclear fusion – a process in which atoms join at extremely high temperatures and release large amounts of energy.
Merkel, who is a doctor of physics, is expected at Wednesday’s event, which is happening in her constituency.
Advocates of nuclear fusion acknowledge the technology is probably decades away but argue that it could replace fossil fuels and conventional nuclear fission reactors.
Construction has begun in southern France on ITER, a huge international research reactor that uses a strong electric current to trap plasma inside a doughnut-shaped device long enough for fusion to take place. The device, known as a tokamak, was conceived by Soviet physicists in the 1950s and is considered fairly easy to build but extremely difficult to operate.
The team in Greifswald is focused on a rival technology invented by the American physicist Lyman Spitzer in 1950. Called a stellarator, the device has the same doughnut-shape as a tokamak but uses a complicated system of magnetic coils to achieve the same result.
That device should be able to keep plasma in place for much longer, said Thomas Klinger, who heads the project. “The stellarator is much calmer,” he said. “It’s far harder to build but easier to operate.”
Known as the Wendelstein 7-X stellarator, the €400m (£300m) device was first fired up in December using helium, which is easier to heat. Helium also has the advantage of “cleaning” any minute dirt particles left behind during the construction of the device.