[Science Scope] 22 Minutes vs. 100 Million Degrees: Who Will Lead the Artificial Sun Race and Anchor the 'Sun' First?

France and China Push the Limits of Duration, Korea Defends the 'Absolute Temperature'
A Decisive Turning Point Toward Commercialization

Editor's Note'Science Scope' is an article series that, true to the meaning of the word 'scope,' zooms in on specific scientific phenomena to examine them in detail, capture them sharply, and provide in-depth analysis.

Conceptual cross-sectional diagram showing the internal structure of the International Thermonuclear Experimental Reactor (ITER) tokamak. The brightly glowing central area is ultra-high-temperature plasma, which is confined suspended in the air by a powerful superconducting magnet. Compared to the person standing below, the scale of the device can be intuitively understood. Provided by ITER Organization

This year, France lasted 22 minutes, and China surpassed the 1,000-second barrier. South Korea also set a new record for maintaining the core benchmark of nuclear fusion, the '100 million-degree plasma,' for the longest duration in experiments conducted from late 2024 to early 2025.

These figures, which recently made headlines in major science sections of global media, mark a milestone, signifying that nuclear fusion has moved beyond the laboratory stage and entered the race for commercialization.

Currently, nuclear fusion has become the front line of the 'energy supremacy war,' with major powers such as the United States, Europe, China, and South Korea vying for energy security and future industrial leadership. Ultimately, the nuclear fusion race is no longer merely a scientific experiment, but has expanded into a next-generation industrial competition encompassing the power grid, semiconductors, hydrogen, and even the space industry.

Why 100 Million Degrees? The First Barrier for the Artificial Sun

Nuclear fusion is a technology that replicates the principle by which the Sun generates energy, but on Earth. The basic idea is that deuterium and tritium, isotopes of hydrogen, fuse together at ultra-high temperatures to become helium, releasing enormous amounts of energy in the process.

This process essentially produces no carbon emissions, and the fuel is abundantly available in seawater. In theory, deuterium from seawater can be used to generate a tremendous amount of energy; it's often said that one liter of seawater contains as much potential energy as several hundred liters of gasoline.

However, Earth is not the Sun. In the Sun's core, immense gravity enables fusion at around 15 million degrees Celsius, but with Earth's much weaker gravity, a far higher temperature is needed to compensate. This is where the '100 million-degree plasma' standard comes in—it represents the practical threshold temperature required for a stable, sustained fusion reaction.

Given that iron melts at about 1,500 degrees and the surface of the Sun is around 6,000 degrees, a 100 million-degree plasma is, in effect, the most extreme thermal environment achievable on Earth.

Only at this temperature can atomic nuclei overcome the electrostatic repulsion between them, collide, and fuse. In essence, nuclear fusion is a technology that forces nuclei to collide at ultra-high temperatures despite their natural tendency to repel each other.

At 100 million degrees, matter enters the 'plasma' state, where electrons are separated from nuclei. The challenge is how to stably confine and control this searing plasma. This is the key factor that determines the success or failure of artificial sun technology.

'Magnetic Prison' to Confine a Flame Without a Vessel: The Tokamak

No physical material on Earth can contain plasma at 100 million degrees; any existing metal would instantly vaporize upon contact. To overcome this, scientists devised a method that uses powerful magnetic fields to levitate and confine plasma in mid-air.

This device is the donut-shaped 'tokamak.' Inside the tokamak, plasma spirals along magnetic field lines generated by superconducting magnets, circulating without touching the walls.

Remi Dumont, a researcher at the French Alternative Energies and Atomic Energy Commission (CEA), explains, "Nuclear fusion is not just about making fire; it's about restraining that fire in mid-air for a long time by binding it with hundreds of millions of magnetic field lines—a sophisticated control technology."

For successful commercialization of nuclear fusion, three conditions must be met simultaneously: plasma density, temperature, and confinement time. In physics, this is known as the 'Lawson criterion.'

Along with the Lawson criterion, the international nuclear fusion community uses the 'Q value' (energy gain factor) as a key metric. This value is the ratio of energy obtained from fusion to the energy invested. For example, Q=1 means the energy produced equals the energy invested, while Q=10 means the energy output is ten times the input.

Generally, a Q value over 1 is considered net energy production, and Q of 10 or higher is regarded as the threshold for commercial power generation. Most current tokamak devices have yet to surpass Q=1.

France's WEST vs. China's EAST: 1,337 Seconds vs. 1,066 Seconds

In February this year, the WEST (Tungsten Environment in Steady-state Tokamak) device at the French Alternative Energies and Atomic Energy Commission (CEA) amazed the world by maintaining plasma for 1,337 seconds (22 minutes, 17 seconds). This engineering achievement demonstrates that the cooling system and inner wall materials can withstand sustained heat loads for a long duration.

Internal view of the WEST tokamak at the French Atomic Energy and Alternative Energies Commission (CEA). Researchers are inspecting the tungsten inner wall structure. WEST demonstrated the possibility of long-duration nuclear fusion operation by maintaining plasma for more than 22 minutes. French Atomic Energy and Alternative Energies Commission (CEA)

What makes WEST's achievement particularly notable is that it was accomplished after replacing all inner walls with tungsten. Previously, carbon was mainly used, but its tendency to absorb hydrogen made it unsuitable for long-term operation. Tungsten, on the other hand, endures ultra-high temperatures but can introduce impurities during interaction with plasma, making control more challenging.

CEA researchers assessed, "This record demonstrates that the capability to control long-duration operation, essential for future fusion power plants, has advanced to a new level."

The EAST (Experimental Advanced Superconducting Tokamak) at the Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP) also stands out for its 'time' record. In January this year, EAST maintained high-performance mode (H-mode) plasma for 1,066 seconds, inaugurating the era of 1,000-second operation.

China's strategy is to invest massive funding and human resources to take the lead in accumulating long-duration operational data. Gong Xianzhu, head of the EAST operation team, emphasized, "The key to future fusion reactors is long-term stable operation, and we are focusing on building up that data."

Overview of the EAST (Experimental Advanced Superconducting Tokamak), a fusion device at the Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP). China is accelerating the competition to secure long-term operation data by maintaining plasma for over 1000 seconds through EAST. Photo by Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP)

Korea's KSTAR: A Technology Powerhouse That Surpassed the '100 Million-Degree' Barrier

Meanwhile, South Korea's KSTAR (Korea Superconducting Tokamak Advanced Research) is recognized as world-leading in terms of 'qualitative difficulty.' In the experiments conducted from late 2024 to early 2025, KSTAR succeeded in sustaining 100 million-degree plasma for 48 seconds with a tungsten divertor environment.

Physically, maintaining tens of millions of degrees for several minutes is far less challenging than maintaining 100 million degrees for several tens of seconds. As the temperature rises, particle motion in the plasma becomes extremely intense, and the confining magnetic field becomes more susceptible to disruption. During this process, plasma turbulence and instability increase dramatically.

This is regarded as evidence that South Korea's ultra-high temperature plasma control technology is at the highest global level. Yoon Siu, Head of the KSTAR Research Division at the Korea Fusion Energy Research Institute, explained, "The ability to stably control ultra-high temperature plasma above 100 million degrees is the key factor that determines the economic viability of commercial power generation."

South Korea is currently replacing the divertor with tungsten and advancing toward its next goal: maintaining 100 million degrees for 300 seconds. This 300-second mark is considered a critical physical milestone for full plasma stabilization.

Panoramic view of the KSTAR nuclear fusion device at the Korea Fusion Energy Research Institute (KFE). KSTAR has achieved world-class results in the field of ultra-high temperature plasma control technology. Provided by Korea Fusion Energy Research Institute

Other Fronts and the 'Final Stage': Laser Fusion and ITER Shaping the Future

Meanwhile, in the United States, a completely different approach to nuclear fusion has already reached a 'historic milestone.' In 2022, the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) succeeded in generating more energy from a laser-based nuclear fusion experiment than was input—humanity's first achievement of 'ignition.'

However, this method is closer to an instantaneous energy release, and significant technical hurdles remain before it can lead to continuous power generation.

Currently, the ultimate testing platform for fusion research is the International Thermonuclear Experimental Reactor (ITER), under construction in Cadarache, France. This mega-project involves the United States, Europe, China, South Korea, Japan, India, and Russia. ITER serves as the core demonstration platform before the commercial nuclear fusion power plant stage (DEMO).

ITER's goal is to achieve 'Q=10,' that is, to produce ten times as much energy as is supplied. If successful, nuclear fusion will shift from a 'possibility' to a 'reality' in the energy industry.

The Achilles' Heel of the Artificial Sun: Instability and Fuel Issues

The most significant physical challenge in nuclear fusion is instability known as ELM (Edge Localized Mode). This refers to a phenomenon in which some plasma bursts through the magnetic field and momentarily ejects toward the wall.

If a chunk of ultra-high temperature plasma strikes the inner wall, it can damage materials or even halt the entire device's operation—making this a key risk factor for commercialization.

Another practical challenge is fuel. Tritium, required for fusion, is almost nonexistent in nature. In actual power plants, tritium must be produced internally using lithium. This process is also considered a major technological barrier to commercialization.

22 Minutes, 100 Million Degrees, and 'Q': The Reshaping of the Energy Order

Ultimately, nuclear fusion power plants are structurally not very different from conventional thermal or nuclear power plants in that they generate electricity by spinning turbines with heat. The difference lies in the source of heat—'fusion' instead of 'fission.'

The most significant difference is safety. Nuclear fusion does not involve chain reactions, so if the conditions are disrupted, the reaction stops immediately. In theory, this means the risk of a 'runaway' accident, as in nuclear power plants, is extremely low.

The reason nuclear fusion is considered a strategic technology is that it is seen as the almost singular solution to simultaneously achieving carbon neutrality and energy security. The International Energy Agency (IEA) has stated, "Fusion is a game changer that will fundamentally transform the power system in the second half of the 21st century."

In the end, France's 22 minutes, China's 1,000 seconds, and Korea's 100 million degrees are not competing against each other. When the final piece—the Q value—falls into place, humanity will, for the first time, complete an 'energy-generating sun' on Earth.

The key question now is: which country will be the first to realize the world's first artificial sun by simultaneously achieving all three requirements—duration, temperature, and energy gain? At that moment, nuclear fusion will cease to be a technology of the future and will become a real industry that rewrites the global energy order.

This content was produced with the assistance of AI translation services.