The world’s largest nuclear fusion project has entered its five-year assembly phase.
Once this is done, the installation will be able to start generating the superheated “plasma” needed for fusion energy.
The £ 18.2 billion (€ 20 billion; $ 23.5 billion) facility is being built in Saint-Paul-lez-Durance in southern France.
Supporters say fusion could be a clean, unlimited source of energy that would help tackle the climate crisis.
Iter is a collaboration between China, the European Union, India, Japan, South Korea, Russia and the United States. All members share the cost of construction.
Nuclear power today relies on fission, where a heavy chemical element is split to produce lighter ones.
Nuclear fusion, on the other hand, works by combining two lightweight elements to make one heavier.
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This releases large amounts of energy with very little radioactivity.
Iter will confine the hot plasma in a structure called a tokamak in order to control fusion reactions.
The project will aim to help demonstrate whether the merger can be commercially viable. French President Emmanuel Macron has said the effort will unite countries around a common good.
The facility could see plasma generated in the machine – a theoretical start of operations – shortly after the assembly phase ends in 2025.
President Macron said: “Iter is clearly an act of confidence in the future. The greatest advances in history have always made bold bets, journeys laden with difficulties.
“At the outset, it always seems that the obstacles will be greater than the will to create and progress. Iter belongs to this spirit of discovery, of ambition, with the idea that, thanks to science, tomorrow may be better than yesterday. ”
Professor Ian Chapman, Director General of the UK Atomic Energy Authority (UKAEA), told BBC News: “This is an extremely exciting phase of the project. Most of us have come to merge to change the world – to make a huge difference. how we provide clean energy for future generations. We all know we need ITER to be successful. ”
“We hope to see the first plasma in five years. It will only be a short plasma – a few milliseconds – demonstrating that all magnets are working. Then it will take an extra step of assembling some of the other components that will have to go into the machine before actually starting to work with hot plasmas. Nonetheless, it marks milestones on the path to demonstrating fusion on a commercial scale. ”
Professor Chapman heads the UK’s Magnetic Containment Fusion research program at the Culham Center for Fusion Energy (CCFE), which operates the Joint European Torus, or Jet, research center. Iter’s Fusion Machine is in many ways a larger-scale version of Jet.
But fusion power has its skeptics. Making it commercially viable has been difficult because scientists have struggled to squeeze enough energy from the reactions.
Proponents believe that Iter can overcome technical hurdles and that, given the planetary challenges it faces, the merger is worth the expense and effort.
The UK is a member of Project Iter but is on the verge of collapse as the UK government pulled out of a key Brexit treaty. The UK could only stay if a new way is found to maintain its involvement by the end of the Brexit transition.
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