Guest essay by Eric Worrall
Germany has activated its new Wendelstein 7-X Stellarator reactor for the first time, briefly testing its ability to heat and contain a Helium plasma. The German Stellarator is the first nuclear fusion reactor ever built which has a chance of hitting break even – or at the very least, of maintaining a sustained nuclear fusion reaction for up to half an hour at a time.
According to World Nuclear News;
After more than a year of technical preparations and tests, the Wendelstein 7-X stellarator has produced its first helium plasma.
On 10 December, the operating team in the control room started up the magnetic field and initiated the computer-operated experiment control system. It fed around one milligram of helium gas into the evacuated plasma vessel and switched on the microwave heating for a short 1.3 MW pulse. The first plasma could be observed by the installed cameras and measuring devices.
The first plasma in the machine had a duration of one-tenth of a second and achieved a temperature of around one million degrees Celsius.
The next task will be to extend the duration of the plasma discharges and to investigate the best method of producing and heating helium plasmas using microwaves.
Project leader Thomas Klinger said, “We’re starting with a plasma produced from the noble gas helium. We’re not changing over to the actual investigation object, a hydrogen plasma, until next year.” He added, “This is because it’s easier to achieve the plasma state with helium. In addition, we can clean the surface of the plasma vessel with helium plasmas.”
Read more: World Nuclear News
A Stellarator differs from a Tokamac by flattening and twisting the Fusion plasma, rather than attempt to hold it in a simple donut shaped magnetic bottle. This twisted configuration diminishes geometric defects in the containment field, reducing the tendency of the plasma to escape magnetic confinement.
Obviously these are early days, but if the German fusion reactor fulfils the research team’s expectations, within the next year or two the German team may demonstrate the first ever completely stable artificial nuclear fusion reaction.