The promise and challenges of nuclear fusion in power generation

Facility in France aims to recreate processes in the sun to facilitate a fossil fuel-free world

- Cheryl Tan

ST-PAUL-LEZ-DURANCE, France Stepping onto the construction site of the Iter facility, soon to be the world's largest experimental nuclear fusion project, is like walking into a world of science fiction.

From supersized magnets that reach heights of over 20m, to the massive scaffolding and immense slabs of concrete, the 180ha site, about the size of 250 football fields, in the south of France is home to a dizzying array of complex engineering work.

This is a project that promises the sun.

Nuclear fusion has been touted as the Holy Grail for clean energy, producing immense amounts of energy with no long-term radioactive waste, a problem associated with conventional nuclear plants, where a uranium atom is split in two to generate power. However, the effort to harness nuclear fusion energy is fraught with technical challenges, including how heat from the reaction can be harnessed economically so it can be used to generate electricity.

Experts say nuclear fusion plants would take decades to become commercially viable, but various research groups, such as those at Iter, are pressing ahead.

By recreating the way in which the sun – a sphere of hot plasma – generates heat and light, nuclear fusion plants essentially replicate the same conditions that allow two forms of hydrogen to fuse.

Short for the International Thermonuclear Experimental Reactor, Iter was built to test a long-held dream of determining whether nuclear fusion, a process that does not release any planet-warming emissions as by-products, can be harnessed as an energy source and eventually generate power at a commercial scale.

It is one of 130 such experimental reactors worldwide – both public and private ones – that aim to see if recreating the processes in the sun can power the world into a future weaned off fossil fuels.