A record that reframes the fusion race
Canada’s General Fusion has reported a new benchmark of roughly 600 million fusion neutrons per second, sharpening global attention on its magnetized target fusion approach. The milestone arrives from a campaign of plasma compression experiments designed to validate key physics at meaningful scale. While not yet a net-energy device, the result strengthens confidence in a pathway toward practical, pulsed fusion power. It also underscores how a clever blend of mechanical compression and magnetic confinement may sidestep some of fusion’s toughest roadblocks.
How magnetized target fusion works
General Fusion’s method, known as magnetized target fusion (MTF), forms a hot, magnetized plasma inside a spherical chamber. Around that chamber sits a swirling layer of liquid metal, which is rapidly compressed by an array of high-power pistons. The liquid metal acts like a dynamic, protective liner, collapsing inward to raise plasma pressure and temperature to fusion-relevant conditions. Because the event is pulsed, the system can achieve extreme compression without relying on ultra-costly superconducting magnets or complex, multi-beam lasers.
Plasma stability at extreme compression
In recent tests, the team reports a plasma density roughly 190 times the initial state, a figure that speaks to successful volumetric compression. Crucially, particle confinement time exceeded the compression time, a regime that supports stable heating and robust performance. The applied magnetic field was amplified by more than 13-fold, strengthening the cage that keeps the plasma hot and well-behaved. The outcome: a significant, repeatable neutron yield and growing evidence that the MTF recipe can be scaled with disciplined engineering.
From PCS experiments to LM26
The company’s Plasma Compression Science (PCS) experiments validated the concept of a collapsing liquid metal liner around a spherical tokamak configuration. According to the team, this marks the first time such a geometry has been compressed with a liner designed to implode in a controlled, symmetrical way. These results feed directly into the Lawson Machine 26 (LM26) program, a next-step platform built to test higher compression, longer confinement, and stronger coupling between the plasma and liner. If successful, LM26 aims to push yields higher and tighten the path to an eventual pilot plant.
Key performance markers
– Approximately 600 million fusion neutrons per second
– Plasma density increased by about 190× during compression
– Magnetic field amplified by more than 13× under implosion conditions
– Particle confinement time exceeded the compression period
– Collapsing liquid metal liner around a spherical tokamak-like target
What industry leaders are saying
“We have demonstrated the viability of a stable fusion process using our MTF approach, laying the foundation for our innovative LM26 project.” — Mike Donaldson, Senior Vice President of Technology Development at General Fusion
This measured confidence reflects more than two decades of iterative R&D, and a shift from small-scale physics to system-level integration. It also highlights that the most promising fusion routes may balance ambitious targets with pragmatic engineering tradeoffs.
Why the pulse matters
MTF’s pulsed nature offers several potential advantages. Short, intense compression events can create fusion-relevant conditions without continuous, high-stress operation of magnets or lasers. The liquid metal forms a neutron-absorbing blanket that protects internal components, enabling heat extraction and straightforward fuel recycling. Over time, such a system could be built for reliability and cost control, reducing maintenance and extending machine lifetimes. It is an architecture designed for manufacturability as much as for core physics.
Scientific context and next steps
As with all fusion claims, the central question is net energy—the point where output exceeds input with clear engineering margins. The current results, published in Nuclear Fusion, do not claim breakeven, but they do show high-yield, stable operation under carefully diagnosed compression. The next waypoint is LM26, which will target stronger coupling, higher pressures, and repeatable performance under power-plant-relevant constraints. The broader goal is a fusion core that can run at meaningful duty cycles with predictable cost per kilowatt-hour.
A credible path to clean power
General Fusion’s advances suggest a practical line through the thicket of fusion challenges. By leaning on mechanical compression and a protective liquid metal liner, the company avoids some of the most expensive and fragile plant components. If LM26 fulfills its promise, the result could be a compact, economical, and scalable fusion system. For policy makers and investors, the message is cautious but optimistic: with sustained support and disciplined execution, pulsed MTF could move from lab success to grid-ready generation.
