China’s ‘Artificial Sun’ Sets a New World Record in Nuclear Fusion

China has broken its own world record in nuclear fusion research, bringing us one step closer to clean and limitless energy. On January 20, 2025, China’s Experimental Advanced Superconducting Tokamak (EAST) reactor kept superhot plasma stable for 1,066 seconds—more than double its previous record of 403 seconds.

What Is Nuclear Fusion?

Nuclear fusion is the process that powers the Sun. It happens when two light atoms combine to form a heavier one, releasing massive amounts of energy. On the Sun, this happens naturally due to extreme pressure. Since we don’t have that kind of pressure on Earth, scientists create fusion by heating plasma (a superhot state of matter) to temperatures much higher than the Sun’s core.

Why Is This Important?

Fusion energy could be the ultimate clean power source—it doesn’t produce greenhouse gases or much radioactive waste. However, scientists have been working on fusion for over 70 years, and we still can’t use it to generate electricity efficiently. The goal is to create a reactor that can sustain itself, but we’re not there yet.

What Makes EAST Special?

EAST is a type of fusion reactor called a tokamak, which uses powerful magnets to keep the plasma trapped inside a doughnut-shaped chamber. Scientists made key upgrades to EAST, including doubling its heating power, which helped it achieve this new record. The challenge is to keep the plasma burning for thousands of seconds so future fusion power plants can operate continuously.

The Bigger Picture

China’s nuclear fusion reactor has broken its own world record for sustaining superhot plasma, marking another milestone in the pursuit of near-limitless clean energy. The Experimental Advanced Superconducting Tokamak (EAST) maintained a steady, highly confined loop of plasma—the high-energy fourth state of matter—for 1,066 seconds on January 20, 2025. This achievement more than doubled its previous best of 403 seconds.

Nuclear fusion reactors are often called “artificial Suns” because they generate energy in a similar way to the Sun—by fusing two light atoms into a single heavier atom using extreme heat and pressure. Since the Sun’s gravity provides immense pressure, Earth-based reactors must compensate by achieving temperatures many times hotter than the Sun’s core.

Fusion energy offers the potential for a nearly unlimited, clean power source with no greenhouse gas emissions and minimal nuclear waste. However, despite over 70 years of research, progress has been slow, and nuclear fusion is not yet a practical solution to the climate crisis.

EAST’s new record does not mean that fusion energy is ready to power cities, but it is a step forward in developing reactors capable of generating electricity. EAST is a magnetic confinement reactor, or tokamak, designed to keep plasma burning for extended periods. So far, no tokamak has achieved ignition—the point where nuclear fusion becomes self-sustaining. However, maintaining long-lasting, stable plasma loops is a crucial step toward that goal.

“A fusion device must achieve stable operation at high efficiency for thousands of seconds to enable the self-sustaining circulation of plasma, which is critical for the continuous power generation of future fusion plants,” said Song Yuntao, director of the Institute of Plasma Physics, Chinese Academy of Sciences.

EAST is one of several fusion reactors worldwide, but all current reactors consume more energy than they produce. In 2022, the US National Ignition Facility (NIF) briefly achieved ignition using a different method that relied on short bursts of energy. However, even in that case, the overall reactor still used more energy than it generated.

Tokamaks, like EAST, are the most common type of fusion reactors. They heat plasma to extreme temperatures and trap it inside a doughnut-shaped chamber using powerful magnetic fields. For this latest record, scientists doubled the power of EAST’s heating system, leading to improved performance.

The data collected from EAST will help advance fusion research worldwide. China is also a key participant in the International Thermonuclear Experimental Reactor (ITER), a global collaboration that includes the US, UK, Japan, South Korea, and Russia.

While fusion energy is not yet ready to replace conventional power sources, EAST’s breakthrough brings us one step closer to making clean, limitless energy a reality in the future.

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