Nuclear fusion can become a promising option to replace fossil fuels as the world’s primary energy source and could have an important role to play in addressing climate change was the overwhelming consensus among participants at the recently concluded International Atomic Energy Agency (IAEA) General Conference on fusion energy research.
However, given that the potential of nuclear fusion to generate electricity at a commercial scale is still some distance away, participants at this virtually organised IAEA event on the status of fusion energy research deliberated on the complexity and challenges of controlling thermonuclear fusion for energy production.
At a conference session, Indian nuclear scientist Meera Venkatesh, who is currently Director of the IAEA’s Division of Physical and Chemical Sciences, noted the challenges in making commercially viable fusion power a reality. She pointed out that finding the right materials to construct the fusion reactor, and developing the mechanism that will be used to extract the massive energy and heat emitted, are among the major tasks ahead. “The realization of fusion power reactors would be a landmark achievement, taking nuclear science and technology to a higher level”, she said.
The most ambitious experiment in this area kicked off last year with the machine assembly of the International Thermonuclear Experimental Reactor (ITER), or the world’s largest nuclear fusion project, starting in Cadarache, France, on July 28. The ITER machine is being assembled to replicate the fusion power of the sun, to enable generation of clean unlimited energy, and the first ultra-hot plasma is expected to be generated in late 2025. The world’s largest science project is intended to demonstrate that fusion power can be generated on a commercial scale.
ITER’s realising of a self-heating plasma is expected to generate 10 times more heat than is put in. Fusion provides clean, reliable energy without carbon emissions, with minute amounts of fuel and no physical possibility of an accident with meltdown. The fuel for fusion is found in seawater and lithium, while it is abundant enough to supply the world for millions of years. A football-sized amount of this fuel is equivalent to around 10,000 tons of coal.
Millions of components from all over the world will be used to assemble the giant reactor, which will weigh 23,000 tonnes. It is a concrete demonstration of the willingness of ITER’s 35 partner countries to join together in an enduring way in their common fight against climate change and for access to limitless clean energy.
ITER Director General, Bernard Bigot highlighted the extensive progress in manufacturing and construction, which is now more than 50 percent completed, with the first experiments scheduled by 2025. ITER is expected to produce 500 MW of fusion power by the late 2030s.
“When we prove that fusion is a viable energy source, it will eventually replace burning fossil fuels, which are non-renewable and non-sustainable. Our mission is to provide a new option which is safe, sustainable and economically competitive. Fusion will be complementary with wind, solar and other renewable energies”, Bigot said.
Another notable fusion experiment in progress at the Max Planck Institute for Plasma Physics in Germany is the world’s largest stellarator — Wendelstein 7-X (W7-X) — a magnetic confinement fusion device that relies primarily on external magnets to confine a plasma, and is designed to serve as an alternative to the “tokamak” (derived from the Russian words for “toroidal magnetic confinement”) reactor like ITER. The stellarator is an inherently stable reactor able to operate the plasma in a steady state for greater lengths of time than the tokamak. Although the W7-X will not produce energy, its potential to operate in a continuous mode will be essential for the commercial operation of a fusion reactor.
Besides the major experiments such as ITER and W7-X, the IAEA conference also discussed the progress made by dozens of start-ups worldwide backed by venture capital funding, which are working on a variety of devices, fuels, and approaches using new technologies in the area of nuclear fusion. “These companies are trying to develop alternative options to ITER. Their investors want to make fusion a reality, and this demonstrates trust in fusion as a promising energy supply for the world in the middle and long term”, Bigot said.
Earlier, at the opening of IAEA’s 28th International Fusion Energy Conference, the agency’s Director General Rafael Mariano Grossi told a virtual audience that global collaboration is vital in developing and deploying fusion technology and that the IAEA would continue to work together with countries, industry and private partners in advancing fusion energy progress.
“After decades of intensive research, scientists and engineers have contributed and witnessed significant steps towards making fusion energy a reality”, Grossi said, describing how since its first edition in 1961, the IAEA’s Fusion Energy Conference had become the foremost global platform for discussing advances in fusion energy research. The previous edition – the 27th _ was held in India at Ahmedabad during 2018 and was hosted by India’s Department of Atomic Energy.
In his address, the IAEA Director General invited countries sponsoring fusion programmes, the fusion industry and private partners to support and jointly participate in an IAEA coordinated feasibility study. The study will encompass the full scope of fusion pilot plant criteria and produce a set of technology-neutral requirements for the safe, secure and commercially viable deployment of future fusion reactors.
A highlight of this year’s conference was the release of IAEA’s upgraded Fusion Device Information System, which, according to the agency, “is an invaluable tool for fusion researchers, compiling information from experimental fusion facilities around the world.”