Canada’s General Fusion has published peer-reviewed scientific results in Nuclear Fusion confirming record achievements in plasma compression using its Magnetised Target Fusion (MTF) technology. The results verify that during the company’s Plasma Compression Science (PCS) experiment series, it produced significant fusion neutron yield by compressing plasmas in the spherical tokamak configuration required for its MTF approach.
In this approach, the proprietary liquid metal liner in the fusion vessel is mechanically compressed by high-powered pistons. This makes it possible to create fusion conditions in short pulses, rather than creating a sustained reaction, while protecting the machine’s vessel, extracting heat, and re-breeding fuel. The technology is designed to scale for cost-efficient power plants. It does not require large superconducting magnets or an expensive array of lasers.
The latest tests proved the effectiveness of the company’s technology for plasma formation and compression using a metal liner, providing the foundation for its Lawson Machine 26 (LM26) – the company’s large-scale fusion demonstration. LM26 will begin integrated operations in early 2025 and is on target to achieve key milestones of 1 keV, then 10 keV (fusion conditions of over 100m degrees Celsius), and, ultimately, scientific breakeven equivalent (100% Lawson criterion) in the next two years.
In the PCS experiment, General Fusion’s high-performing plasmas remained stable and maintained magnetic flux while the fusion neutron yield increased significantly. The experiment results demonstrated that significant volumetric compression of a spherical tokamak plasma is practical, de-risking LM26, which will compress plasmas at large scale to reach higher fusion yields.
Neutron yield increased significantly, exceeding 600m neutrons per second in one compression shot. During compression, the plasma became approximately 190 times denser than when it started, consistent with plasma particle confinement time being significantly longer than the compression time. The magnetic field that provides robust confinement for the hot plasma became over 13 times higher due to the action of compression. Measurements of plasma heating agreed well with the rate expected for the scale of the experiment, with a modest rise in ion temperature to approximately 0.63 keV during the compression.
“During our PCS series, General Fusion was the first in the world to compress a spherical tokamak plasma with a collapsing metal liner, and we are thrilled to now share in a peer-reviewed publication the results we achieved in demonstrating fusion from MTF through this experimental campaign,” said Dr Michel Laberge, General Fusion Founder and Chief Science Officer. “Now, we’re approaching breakthrough milestones with LM26. Our practical approach translates to an economical power plant, putting us on the path to electricity on the grid by the early to mid-2030s.”
“We’ve demonstrated the viability of a stable fusion process using our MTF approach, laying the foundation for our groundbreaking LM26,” said Mike Donaldson, General Fusion Senior Vice President, Technology Development. “Through our PCS series, we also made major advances in plasma systems, materials, coatings, and diagnostics. Now we’re ready for the next step – demonstrating fusion and significant heating at large scale with LM26.”
The LM26 fusion demonstration machine is on track to achieve transformative technical milestones in the next 24 months – 1 keV in the first half of 2025, then 10 keV, and ultimately scientific breakeven equivalent (100 per cent Lawson criterion) by 2026. Its results will significantly de-risk the company’s commercial-scale machine, fast-tracking its path to provide commercial fusion energy to the grid by the early to mid-2030s.
