Nuclear fusion milestones from Canada’s General Fusion and China’s EAST reactor have caused a buzz over this potentially limitless, clean energy source becoming a reality amid rising power demand from AI and electrification. Meanwhile, new fusion startups have been popping up around the world and have drawn billions in private investment.
Here’s a closer look at nuclear fusion and where its development is at in Canada and the world.
What is nuclear fusion?
Nuclear fusion has been researched for decades as a way of producing clean, safe, limitless energy from an abundant source.
Fusion happens when nuclei at the centres of two atoms combine into a single nucleus, forming a heavier element and releasing a huge amount of energy. Combining hydrogen nuclei into helium powers our sun. The same reaction can be used in reactors on Earth.
Hydrogen, the fuel for that reaction, is widely available in water on Earth. And unlike the reactions in traditional nuclear reactors, which split atoms of radioactive elements such as uranium, fusion reactions don’t generate radioactive waste. But commercial nuclear fusion reactors are not yet available.
The host of CBC’s Quirks & Quarks explains the process of getting clean energy from nuclear fusion, and points to Canadian and French projects that are also underway.
Why is nuclear fusion in the news lately?
China’s EAST (Experimental Advanced Superconducting Tokamak) fusion reactor recently reached an important milestone. Fusion reactors need to keep hydrogen extremely hot and condensed, in the form of plasma, as it’s found in the sun. The Chinese Academy of Sciences announced earlier this month that EAST had kept plasma stable at densities beyond a previous limit. That may enable the production of smaller, cheaper commercial fusion reactors in the future, Nature reports.
Robert Fedosejev, a University of Alberta professor who has been involved in laser fusion research for more than 50 years, said those results had been predicted years ago, although actually doing it is “a step forward.”
A November 2024 announcement from General Fusion, based in Richmond, B.C., also resurfaced in the news this month, which is described as a “world record” in the production of neutrons — byproducts that show how much fusion occurred.
Fedosejev said the record applies only to General Fusion’s own technology — some government-funded fusion reactors have done orders of magnitude more fusion with other technologies. However, he added, General Fusion is “farther along than most [fusion] startups who’ve not produced neutrons at all.”
Creating the conditions of the sun on Earth has been a decades-long, global challenge — but if we crack it, it could mean limitless clean energy. Johanna Wagstaffe visits a Canadian company betting on a bold new approach to get there first.
Both recent developments are important, but incremental, said Blair Bromley, past-co-chair of the Fusion Energy and Accelerator Science and Technology Division of the Canadian Nuclear Society.
In other Canadian fusion news, a new Centre for Fusion Energy in Ontario was announced less than two months ago. It will be established with $33 million from the federal government and Crown corporation Atomic Energy of Canada Ltd., $19.5 million from the Ontario government and Crown corporation Ontario Power Generation, and $39 million from fusion startup Stellarex Group Ltd. Stellarex says the centre’s mission would include the design, construction and operation of a demonstration reactor, but has offered no timeline.
Why is there global interest in fusion lately?
Andrew Holland is CEO of the Fusion Industry Association (FIA), a global organization that says it represents all the major private fusion companies in the world outside China.
Holland said investors around the world are thinking about climate change and energy security amid growing demand for energy from data centres and AI: “Ideally, we need a lot more carbon-free, always-on, always available energy. Fusion can solve that.”
Meanwhile, “the science has progressed to the point where … companies are confident that the next machine they build will work,” he said.
The industry group was founded in 2021 with 24 member companies. In the past five years, the number of fusion companies has more than doubled to 53, and over $10 billion US has been invested in private fusion startups.
Investors include tech companies Microsoft and Google, billionaires Bill Gates and Jeff Bezos and the oil company Chevron.
The FIA says a majority of its members expect to see fusion producing electricity for the grid in the 2030s.
That sounds optimistic. How close are we, actually?
A challenge for fusion has been the huge amount of energy that needs to go into even getting the reaction started.
Three years ago, a fusion reaction at the National Ignition Facility of Lawrence Livermore National Laboratory in the U.S. generated slightly more energy than was put in. That was the first time (and the only time so far) a fusion reaction had ever produced net energy.
Fedosejev said that “really raised the awareness and, I guess, the optimism.”
U.S. scientists say they’ve produced a fusion reaction that creates a net energy gain, a major breakthrough in the decades-long quest to create limitless, cheap green energy through nuclear fusion. However, it could still be years before this science is used to generate sustainable power.
But getting out slightly more energy than was put in isn’t good enough. The ratio needs to be much higher in a power plant.
ITER (the International Thermonuclear Experimental Reactor), a huge fusion reactor being built in France with the collaboration of China, the European Union, India, Japan, Korea, Russia and the U.S. at an estimated cost of 13 billion euros ($21 billion Cdn) aims to achieve that. It will use 50 megawatts of electricity to generate 500 megawatts of fusion power — roughly 10 times better than LLNL, and enough to power roughly 250,000 homes — and to be operational in the late 2030s.
Fedosejev said scientists are fairly confident that a fusion reactor that big will be able to do this.
Video from inside a reactor as European scientists set a world record for producing fusion energy. Though many years away, the process has the potential to create energy without pollution, radioactive waste or greenhouse gases.
But other challenges remain before we have operational fusion power plants.
The extreme heat and radiation produced by fusion reactions damage the reactor, limiting its operational lifetime to roughly “less than an hour total operating time,” said Fedosejev, although that would be divided over more than a dozen runs of a few hundred seconds. Extending that will require some engineering and solutions such as new materials.
Canada’s role in fuelling fusion
In addition to the challenges with output, no one has yet created a self-sustaining fuel system.
Today’s fusion reactors rely on combining two different kinds of hydrogen called deuterium and tritium.
Deuterium is found naturally in water, but tritium is manufactured using neutrons and lithium. In the future, engineers aim to create a system that feeds the neutrons produced by fusion reactions into a “breeder” container of lithium that will generate more tritium, but that doesn’t yet exist.
In the meantime, tritium needs to be made elsewhere and fed into the reactor.
Most of the world’s commercial tritium is currently produced by Ontario’s CANDU nuclear reactors.
Canada supplies tritium and tritium-related equipment and technology to ITER, and it will supply tritium to the United Kingdom Atomic Energy Authority for nuclear fusion.
Costs need to come down
While giant reactors like ITER may be able to generate fusion power, they’re extremely expensive. The question now is whether commercial fusion reactors can become economically competitive with other zero-carbon sources of electricity, Bromley said. Fusion aims to compete with more continuous “baseload” sources, such as traditional nuclear and hydro. Meanwhile, solar and wind are already cheaper than fossil fuels.
That’s why fusion startups are trying to find ways to make smaller, cheaper reactors using new technologies such as high-temperature superconducting magnets.
Bromley says the science is at the point that private industry can work in parallel with governments on many of the practical technological and engineering challenges.
“A lot of people in the private sector have thought, you know, this is a problem, this is an opportunity to make profit and to address a problem of, of worldwide need,” he said.
Holland says he thinks we’re now close enough to fusion reactors that industry needs to start creating supply chains and governments need to start getting public policy and regulations in place to support them.
“We’ve got to start getting people aware that this is coming,” he said. “We have to make sure that people know and understand how exciting this is so that they actually want this thing built in their communities.”




