History
The firm was founded in 2002 by former Creo senior physicist and principal engineer Michel Laberge.[8]
In 2005 it produced a fusion reaction in its first MTF prototype. In 2010, it produced its first at-scale plasma injector with magnetically confined plasma. In 2011 it first demonstrated compressive heating of magnetized plasma.
A proof-of-concept compression system was built in 2013 with 14 full size pistons arranged around a 1-meter diameter spherical compression chamber to demonstrate pneumatic compression and collapse of a liquid metal vortex.[9][10] The pneumatic pistons were used to create a converging spherical wave to compress the liquid metal. The 100 kg, 30 cm diameter hammer pistons were driven down a 1 m bore by compressed air.[10] The hammer piston struck an anvil at the end of the bore, generating a large amplitude acoustic pulse that was transmitted to the liquid metal in the compression chamber.[10] To create a spherical wave, the timing of these strikes had to be controlled to within 10 μs. The firm recorded sequences of consecutive shots with impact velocities of 50 m/s and timing synchronized within 2 μs.[10] However it was found that the wall of the liquid metal vortex turned to a spray soon after the arrival of the pressure wave.[10]
From its inception until 2016, the firm built more than a dozen plasma injectors.[11] These include large two-stage injectors with formation and magnetic acceleration sections (dubbed "PI" experiments), and three generations of smaller, single-stage formation-only injectors (MRT, PROSPECTOR and SPECTOR).[12] The firm published research demonstrating SPECTOR lifespans of up to 2 milliseconds and temperatures in excess of 400 eV.[12]
As of 2016, the firm had developed the power plant's subsystems, including plasma injectors and compression driver technology.[13] Patents were awarded in 2006 for a fusion energy reactor design,[14] and enabling technologies such as plasma accelerators (2015),[15] methods for creating liquid metal vortexes (2016)[16] and lithium evaporators (2016).[17]
In 2016 the GF design used compact toroid plasmas formed by a coaxial Marshal gun (a type of plasma railgun), with magnetic fields supported by internal plasma currents and eddy currents in the flux conserver wall.[18] In 2016, the firm reported plasma lifetimes up to 2 milliseconds and electron temperatures in excess of 400 eV (4,800,000 °C).[12]
Around 2017 the company performed a series of experiments named Plasma Compression Small (PCS). These implosion experiments used a chemical driver to compress an aluminum liner onto a compact toroid plasma. Because the implosions involved chemical explosives, the tests took place outdoors in remote locations. The tests were destructive and could only be executed every few months. These tests were carried out to advance the understanding of plasma compression with the goal of advancing toward a nuclear-reactor scale demonstration.[19][20][21]
As of December 2017, the PI3 plasma injector held the title as the world's most powerful plasma injector, ten times more powerful than its predecessor.[22] It also achieved stable compression of plasma.
In 2019 it successfully confined plasma within its liquid metal cavity. From 2019 to 2021 it increased plasma performance.
As of 2021, the firm demonstrated compression of a water cavity into a controlled, symmetrical shape.[23]
Also in 2021 the company agreed to build a demonstration plant in Oxfordshire, at Culham, the center of the UK's nuclear R&D. The plant is planned to be 70% of the size of a commercial power plant. The company claimed it had validated all the individual components for the demonstration reactor.[24]
In 2022, the company announced that it had completed 200,000+ plasma shots, filed 150 patents/patents pending, and that headcount had passed 200. PI3 reached 10 ms confinement times and temperatures of 250 eV, almost 3 million degrees Celsius, without active magnetic stabilization, auxiliary heating, or a conventional divertor. Its primary compression testbed, a 1:10 scale system using water rather than liquid metal,[25] has completed over 1,000 shots, behaving as predicted.[23]
According to the 2023 Fusion Industry Association report, the company has 150 employees and has raised approximately USD $300,000,000+.[26]
In 2023, the firm reduced headcount significantly and announced that it was building a new machine, "LM26", with the goal of achieving breakeven by 2026. The Fusion Demonstration Plant being built in the UK will be delayed.
In May 2025, the firm again announced layoffs of about 25% of its workforce and reduction in operation of LM26, following an "unexpected and urgent financing constraint."[27]
In January 2026, General Fusion announced plans to become a public company via a special purpose acquisition company merger by the middle of the year.[28]
