China one step closer to harnessing clean, limitless energy from nuclear fusion
China acknowledged as global leader in the field and world’s only nation increasing funding into research to draw energy from ‘artificial sun’
On a quiet, scenic peninsula jutting out into Hefei’s Dongpu Reservoir, physicists recently set a world record, creating hydrogen plasma, hotter than the core of the sun, that burned steadily for more than a minute.
The nuclear fusion researchers kept the ionised gas burning steadily for twice as long as the previous record, set four years ago at the same reactor on Science Island, home to some of China’s largest research facilities.
Professor Luo Guangnan, deputy director of the Experimental Advanced Superconducting Tokamak (EAST) facility in Anhui’s provincial capital said some previous fusion experiments had lasted for more than 100 seconds, but they were like “like riding a bucking bronco”, with plasma that was volatile and difficult to control.
However, the experiment conducted at EAST in August was more like a dressage event, with the plasma tamed in a high-performance steady state, known as H-mode, in a donut-shaped chamber shielded by a extremely strong electromagnetic field.
“It is a milestone event, a confidence boost for humanity to harness energy from fusion,” Luo told the South China Morning Post.
Physicists view H-mode as an optimal working scenario for a future fusion power plant, and the one-minute breakthrough owed a great deal to the Chinese government’s heavy investment on fusion research in recent years.
While still a long way short of the duration required to make commercialisation of the technology possible – which would be measured in decades, not minutes – scientists say the breakthrough shows the pace of development on fusion research in China is leaving other nations in the dust.
It could also help accelerate government approval of construction of the world’s first fusion power plant, the proposed Chinese Fusion Engineering Test Reactor (CFETR).
Fusion occurs when two hydrogen nuclei merge to form an atom of helium. During the process, a small amount of mass is converted into an enormous amount of heat. The challenge is to bring that energy under control.
Many fusion research facilities have been set up around the world in attempts to solve the fusion-control problem, with the largest facility under construction, the International Thermonuclear Experimental Reactor (ITER) in France, expected to fire its first pulse of plasma by 2025.
But all such facilities are relatively primitive, with none able to turn fusion power to electricity.
The CFETR proposal sees the reactor going into operation in 2030, generating 200 megawatts of power initially, before an upgrade in the following decade that would ramp up output to around a gigawatt, more than is produced by each of the commercial fission reactors at Daya Bay.
“It is hoped that the proposal for CFETR construction can be approved by the government within the next five years,” Wan Yuanxi, a leading fusion research scientist with the Chinese Academy of Sciences, told an international fusion science conference in Kyoto, Japan, last month.
Luo, who is also involved in the CFETR project, said China’s commitment to fusion research stood out when compared to other countries.
“China is the only nation in the world increasing its budget for fusion research,” he said. “The funding in Europe has been dwindling, a proposal for the construction of new research facilities in the US was rejected by Congress, and progress in Japan has also stagnated.”
The one-minute H-mode breakthrough at EAST was made possible by financial support from the central government, which allowed the EAST team to undertake a series of major upgrades in the past few years.
In contrast, the Alcator C-Mod tokamak nuclear fusion reactor at America’s Massachusetts Institute of Technology, which set many world records in 23 years of service, shut down in September due to federal government budget cuts in the United States. It set its last world record, for the highest plasma pressure, on its final day of operation.
The funding and opportunities available in China have attracted fusion scientists from around the world, eager to solve the world’s energy shortage and environmental pollution problems once and for all.
Many American researchers were involved in EAST’s one-minute H-mode experiment.
“In each of our experiments in recent years, the number of foreign participants easily exceeded 100,” Luo said, acknowledging that the progress in China would not have been so fast without a collective effort by international community.
The rapid pace of development in China has, however, led to concerns in other countries, worried that if China is the first to commercialise fusion technology it will gain the upper hand economically and geopolitically.
There was even discussion among the other six ITER members – Japan, South Korea, Russia, the US, India and the European Union – about kicking China out of the project because of concerns it would use knowledge gained from ITER to accelerate construction of CFETR.
But ITER, plagued by years of delay and way over budget, would not survive without China’s support, and the country’s influence in the project has grown significantly in recent years. The number of ITER employees from China has gone from last place among its seven members to second, trailing only the EU.
Professor Steven Cowley, president of Corpus Christi College, Oxford, and former head of Britain’s Culham Centre for Fusion Energy, said the best choice for other countries was to embrace, and even support, China’s leadership in fusion research.
“I think that CFETR is a bold and important move – not just for China but for the world,” Cowley said. “It will not undermine ITER but rather move on rapidly from ITER towards full commercial fusion power.
“If China is first that is great since it will really benefit everyone. I would like to see us all help China to accelerate the pace of fusion development. Certainly the EU would also like to be first to commercial fusion power – but the most important thing is that someone does it as soon as possible.”
But the Chinese government might have other considerations. While budget estimates for the CFETR project have not been publicly released, a fusion reactor is likely to cost much more than a commercial fission reactor, and many technological hurdles remain unsolved.
The recent EAST experiment, for instance, had to be terminated because the researchers were afraid that letting it run for longer might damage the facility beyond repair.
China has also embarked on the world’s most ambitious conventional nuclear power plant construction programme and that heavy investment might leave less funding available for large, experimental projects like CFETR.
Then there’s also the question of whether large, government-funded fusion projects will be able to reach the stage of commercialisation faster than smaller projects carried out by private companies funded by venture capital. In recent years, several start-ups have been established in the US to approach fusion with technology different from the donut-shaped tokamak, an old design proposed by former Soviet scientists more than 50 years ago.
But some scientists from private companies overseas are also working in Chinese facilities. Wan told the conference in Kyoto that the CFETR project had participants from General Atomics, a defence contractor headquartered in San Diego, California, that specialises in nuclear physics, as well as others from the US Department of Energy’s Princeton Plasma Physics Laboratory.
“I have a dream, to see a light bulb lit by the power of fusion within my lifetime,” Li Jiangang, a leading Chinese fusion scientist, said in a programme on China Central Television in April. “This light bulb will be, and has to be, in China.”