Engineers building parts of a new type of power plant for generating green energy with nuclear fusion are using their expertise from building rockets like Europe’s Ariane 5 to create the super-strong structures to cope with conditions similar to those inside the Sun.
A technique for building launcher and satellite components has turned out to be the best way for constructing rings to support the powerful magnetic coils inside the machine.
Meaning “the way” in Latin, the International Thermonuclear Experimental Reactor, ITER, is the world’s largest nuclear fusion experiment on generating electricity and is now being built in France.
Spanish company CASA Espacio is making the rings using a method they have perfected over two decades of building elements for the Ariane 5, Vega and Soyuz rockets, as well as for satellites and the International Space Station.
“Forces inside ITER present similar challenges to space,” explains Jose Guillamon, Head of Commercial and Strategy.
“We can’t use traditional materials like metal, which expand and contract with temperature and conduct electricity. We have to make a special composite material which is durable and lightweight, non-conductive and never changes shape.”
At their centre of excellence in Spain with its track record in composites for space applications, CASA Espacio has been at the forefront of developing a technique for embedding carbon fibres in resin to create a strong, lightweight material.
The composite is ideal for rocket parts because it retains its shape and offers the robust longevity needed to survive extreme launches and the harsh environment of space for over 15 years.
Now, the team is using a similar technique to build the largest composite structures ever attempted for a cryogenic environment. With a diameter of 5 m and a solid cross-section of 30×30 cm, ITER’s compression rings will hold the giant magnets in place.
Harnessing star energy
Nuclear fusion powers the Sun and stars, with hydrogen atoms colliding to form helium while releasing energy. It has long been a dream to harness this extreme process to generate an endless supply of sustainable electricity from seawater and Earth’s crust.
In a worldwide research collaboration between China, the EU, India, Japan, South Korea, Russia and the US, the first prototype of its kind is now being realised in ITER.
Construction is expected to be completed by 2019 for initial trials as early as 2020. A commercial successor for generating electricity is not predicted before 2050.
Designed to generate 500 MW while using only a tenth of that to run, ITER aims to demonstrate continuous controlled fusion and, for the first time in fusion research, produce more energy than it takes to operate.
Inherently safe with no atmospheric pollution or long-lived radioactive waste, one kilogram of fuel could produce the same amount of energy as 10 000 tonnes of fossil fuel.