The results, submitted for peer review and publicly available, demonstrate significant progress toward key 1 keV electron temperature milestone

VANCOUVER, British Columbia, June 22, 2026 (GLOBE NEWSWIRE) -- General Fusion Inc. ("General Fusion" or the "Company"), a leader in the global race to commercialize fusion energy, has achieved significant progress toward its next major technical milestone with its innovative large-scale Magnetized Target Fusion ("MTF") machine, Lawson Machine 26 ("LM26").

The results show meaningful plasma heating to electron temperatures of approximately 8.4 million degrees Celsius or 0.72 keV, driven by the compression of a plasma with a lithium liner. This is a key indicator of success for the Company's uniquely practical approach to fusion energy.

These results are detailed in a technical paper being concurrently posted on General Fusion's website and submitted for peer review.  

LM26 is the first MTF demonstration machine to be built at a commercially relevant scale, and it mechanically compresses plasma with a lithium liner. The Company's next major targeted milestone with LM26 is 1 keV electron temperature.

Since it started operating in 2025, LM26 has completed a series of plasma compressions with results that advance the Company's groundbreaking technology. These results, detailed in the technical paper, include:

Electron temperature of approximately 8.4 million degrees Celsius (0.72 keV +/- 0.08), which represents a more than 3 times increase in electron temperature during mechanical compression, largely due to plasma compressional heating. This is believed to be a unique result for General Fusion's practical MTF approach, which uses a plasma solely heated by mechanical compression after it is formed. These results are supported by multiple diagnostics, including Thomson scattering and Absolute Extreme Ultraviolet (AXUV) systems.

Significant plasma density and poloidal magnetic field increases during compression, both to 10 times starting values; these increases are similar to or better than results achieved in prior General Fusion test beds and at significantly larger scale.  

Plasma stability until deep into compression.

No significant plasma contamination by the lithium liner during the stable compression phase.

Observed increase in neutron yield during compression.

The Company believes these results validate the operating principles of the LM26 machine and lay the foundation for planned increases in starting plasma parameters that are expected to enable the mechanical compression of plasma to increasingly higher densities and temperatures. While these preliminary results undergo peer review for potential scientific journal publication, the Company intends to continue optimizing LM26 performance toward achieving 1 keV electron temperature, its first major targeted milestone.

"We are forging a new path in fusion with our uniquely practical MTF approach. The results announced today are all key indicators of real-world progress toward our targeted technical milestones with LM26," said Greg Twinney, Chief Executive Officer at General Fusion. "I am grateful to our team for their unwavering dedication and expertise, as well as our collaborators at the UK Atomic Energy Authority, Princeton Plasma Physics Laboratory, General Atomics, and others who have supported our diagnostic efforts with LM26."

"The LM26 experiments have delivered an important validation of General Fusion's Magnetized Target Fusion approach," said Tony Donn?, Chair of General Fusion's Science and Technology Advisory Committee and former Chief Executive Officer of EUROfusion. "The observed increases in magnetic field, plasma density, and electron temperature during compression demonstrate substantial technical progress and are consistent with the expected behavior from modelling and simulations. The agreement between experiment and theory is particularly encouraging, as it provides confidence that the planned machine upgrades will enable access to even more demanding plasma conditions and bring the technology closer to its next major milestones."

General Fusion previously announced execution of a business combination agreement with Spring Valley Acquisition Corp. III ("Spring Valley" or "SVAC") (the "Proposed Business Combination"). At the closing of the Proposed Business Combination, Spring Valley will be renamed "General Fusion Group Ltd.," and the combined company's shares and warrants are expected to trade on Nasdaq under the ticker symbols "GFUZ" and "GFUZW," respectively, subject to approval of its listing application. Spring Valley set a meeting date of July 6, 2026, for its extraordinary general meeting of shareholders to approve the Proposed Business Combination. If the Spring Valley and General Fusion securityholders vote to approve the Proposed Business Combination, the transaction is expected to close shortly thereafter, subject to the satisfaction of customary closing conditions. 

Quick Facts:

General Fusion's Magnetized Target Fusion ("MTF") is designed to solve significant barriers to commercializing fusion energy at a time when electricity demand is surging, and nations around the world are racing to commercialize fusion power.

As a technology, MTF aims to achieve fusion in a practical way, avoiding superconducting magnets and high-powered lasers, while enabling the use of existing materials for durable machines that would produce cost-effective energy.

In early 2025, General Fusion announced that it had designed, built, and begun operating its Lawson Machine 26 ("LM26") fusion demonstration machine in under two years. LM26 is the first MTF demonstration machine to be built at a commercially relevant scale. It mechanically compresses plasma with a lithium liner at 50% commercial-scale diameter, based on current design parameters.  

LM26 aims to achieve key fusion technical milestones: plasma heating to 1 keV (10 million degrees Celsius), then 10 keV (100 million degrees Celsius), and ultimately the Lawson criterion, the combination of fusion parameters that can produce net fusion energy in the plasma.

About General Fusion

General Fusion is pursuing a fast and practical approach to commercial fusion energy and is headquartered in Vancouver, Canada. The Company was established in 2002 and has been funded by a global syndicate of leading energy venture capital firms, industry leaders, and technology pioneers. Learn more at www.generalfusion.com.

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