Chinese scientists have made a breakthrough in fusion energy that could finally overcome one of the most persistent barriers to the development of this technology. The Chinese Academy of Sciences (CAS) team said their experimental nuclear reactor called “Artificial Sun” achieved a plasma density previously thought impossible. The research, published by ScienceAdvances, aims to be a new advance in a type of energy that is considered essential for the coming decades.
Fusion energy (Nuclear Fusion) promises to one day deliver safe, abundant and environmentally responsible energy. Although it is not harmless (no known way of generating energy is 100%) since it produces radioactive tritium and the walls of the reactors become radioactive due to the plasma, it is included in the group of clean energies as it does not produce gases that contribute to global warming.
It must be said that Fusion has been researched since 1950 and is considered the “energy of the stars” since it activates stars like our Sun. Fusion involves the release of energy through the union of atomic nuclei, contrary to that caused by nuclear fission used in nuclear power plants and atomic bombs.
China and its ‘artificial sun’
The theory of how Nuclear Fusion works is well known. The problem is that at this time we do not have the technical capabilities to harness this power. Scientists around the world are currently working to achieve this, including China with an ambitious project that is advancing at a key moment where AI energy consumption threatens global sustainability.
In recent years there have been important advancesincluding milestones achieved on the CAS Advanced Experimental Superconducting Tokamak. Last year, it successfully ran its artificial solar reactor for more than 1,000 seconds for the first time, a record that was later surpassed by France’s WEST machine.
Both experiments were limited by the theoretical density ceiling, known as the Greenwald Limit, which causes the fuel (or plasma) to become unstable above a certain level. Using a new process called plasma wall self-organization, CAS researchers managed to keep plasma stable at unprecedented levels of density.
The researchers said that by pushing plasma density far beyond empirical limits, fusion ignition can be achieved with much higher energy outputs. “The findings suggest a Practical and scalable path to expanding density limits in tokamaks and next-generation burning plasma fusion devices”explains the chief researcher of the Chinese artificial sun project.
Practical energy production through nuclear fusion still requires significant advances to be realized on a large scale, although several startups are already planning to implement it For example, US-based Helion Energy secured the world’s first nuclear fusion power purchase agreement in 2023, promising to provide 50 MW of fusion power to Microsoft by 2028.
