Japan fires up world's largest nuclear fusion reactor

The world's largest and most advanced nuclear fusion reactor has kicked off operations, thanks to a joint venture between the European Union and Japan.

The development of the JT-60SA reactor began on December 1st 2023 in Japan’s Ibaraki Prefecture - and aims to leverage the next-generation energy source.

Although still in its experimental phase, scientists believe it could hold promise for addressing humanity's sustainability needs, presenting nuclear fusion as a clean - and almost limitless - energy source.

National Institutes for Quantum Science and Technology/ Monty Rakusen / Getty

Deputy project leader for the JT-60SA, Sam Davis, said the device will 'bring us closer to fusion energy.'

Whilst plasma physicist Arthur Turrell - unaffiliated with the project - hailed the success as a 'moment of history' that could 'define a new era of energy.'

Nuclear fusion replicates natural reactions within the sun, potentially providing a solution to our sustainability challenges and the ongoing fossil fuel crisis. Therefore, the JT-60SA reactor requires zero fossil fuel consumption and generates zero high-level hazardous or radioactive waste.

One scientist of the project commented: 'Because of these characteristics, fusion qualifies as one of the next-generation energy sources that simultaneously addresses energy supply and environmental challenges.'

Following the prior success of achieving net energy gain with nuclear energy, a year earlier at the Lawrence Livermore National Laboratory in California, JT-60SA has advanced the data - achieving an 'even greater net energy gain than the first time.'

National Institutes for Quantum Science and Technology/ Monty Rakusen / Getty

Situated in a hangar in the northern Naka region of Tokyo, the six-storey-high JT-60SA reactor uses a 'tokamak' vessel to contain heated swirling plasma up to 200 million degrees Celsius. Researchers of JT-60SA said the fusion reaction is 'intrinsically safe' as it 'stops when the fuel supply or power source is shut down.'

Fusion energy differs from fission energy - the common method used in nuclear power plants - in that it combines two atomic nuclei rather than splitting one. Although it was first recognised in the 1950s, only recently have scientists discovered its potential to scale 'within the next decade.'

'The generation of fusion energy does not produce carbon dioxide, making it an important technology in the path to net zero emissions,' the EU's directorate-general for energy said.

JT-60SA precedes its big brother reactor - ITER - which stands for International Thermonuclear Experimental Reactor. Currently undergoing construction in France, the next nuclear fusion reactor is expected to open in 2025. However, with concerns its costs going over budget, it may lead to delays.