Pump out the volume

Coconuts aren’t usually the first thing that spring to mind when you think about clean energy sources. But it turns out they could be an important component of attempts to make nuclear  fusion a commercial reality.

Currently under construction in southern France, Iter will be the world’s largest experimental fusion reactor. It will replicate in a power station the sort of reactions that power the Sun and stars – the fusion of hydrogen isotopes into helium – in order to deliver safe, effectively limitless and environmentally clean energy on a commercial scale.

Success in controlling nuclear fusion  rests on using vacuum pumps to create large volumes of nothingness: any extraneous material would get in the way of the fusion reactions. Iter’s fusion reactions will happen inside a huge, 1,400m³ toroidal vacuum chamber sat inside a cryostat – a massive ‘vacuum flask’. Liquid helium will flow around this assembly, keeping the reaction chamber and cryostat at a temperature of 4.5K.