VANCOUVER, British Columbia, March 24, 2026 (GLOBE NEWSWIRE) -- General Fusion Inc. ("General Fusion" or the "Company"), a leader in the global race to commercialize fusion energy, today announced a new peer-reviewed publication in the scientific journal Fusion Science and Technology demonstrating a key diagnostic system for measuring temperature milestones in its world-first, large-scale Lawson Machine 26 ("LM26") fusion demonstration machine.

The Company previously announced its plans to go public through a business combination (the transactions contemplated by the business combination, collectively, the "Proposed Business Combination") with Spring Valley Acquisition Corp. III (NASDAQ: SVAC) ("SVAC"). 

General Fusion's LM26 is designed to reach target temperatures of 1 keV (10 million degrees Celsius) and 10 keV (100 million degrees Celsius) and ultimately achieve the Lawson criterion, demonstrating the Company's Magnetized Target Fusion ("MTF") technology in a commercially relevant way. In LM26, temperature analysis will draw on multiple diagnostics, including ion temperature measurements through neutron counting. The new peer-reviewed research in Fusion Science and Technology outlines the Company's advancement of this diagnostic method for its MTF approach.

"Ion temperature is a key parameter for fusion performance in our LM26 program," said Mike Donaldson, Senior Vice President of Technology Development at General Fusion. "Our work demonstrates a practical, scalable method to measure ion temperature using neutron counting. As we move toward 1 keV and beyond, this technique will be an important tool for validating plasma performance in LM26."

General Fusion has more than 20 years of experience designing, building, and testing fusion prototypes and testbeds. The publication in Fusion Science and Technology highlights General Fusion's deep expertise in developing fusion diagnostics for MTF and builds on work from PI3, the world's largest and most powerful operational fusion plasma injector, now integrated into LM26. Temperature measurements from LM26 will also be supported by data from absolute extreme ultraviolet (AXUV) diodes measuring electron temperature. The machine's comprehensive diagnostic suite further includes magnetic sensors, neutron detectors, spectroscopy, and laser-based systems.

Quick Facts:

General Fusion's 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 world-first 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.

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.

Important Information for Investors and Shareholders

In connection with the Proposed Business Combination, General Fusion and SVAC filed with the SEC the Registration Statement, which includes a preliminary prospectus with respect to SVAC's securities to be issued in connection with the Proposed Business Combination and a preliminary proxy statement in connection with SVAC's solicitation of proxies for the vote by SVAC's shareholders with respect to the Proposed Business Combination and other matters described in the Registration Statement (the "Proxy Statement"). After the SEC declares the Registration Statement effective, SVAC plans to file the definitive Proxy Statement with the SEC and to mail copies to SVAC's shareholders as of a record date to be established for voting on the Proposed Business Combination. This document does not contain all the information that should be considered concerning the Proposed Business Combination and is not a substitute for the Registration Statement, Proxy Statement or for any other document that SVAC has filed or may file with the SEC. Before making any investment or voting decision, investors and security holders of SVAC and General Fusion are urged to read the Registration Statement and the Proxy Statement, and any amendments or supplements thereto, as well as all other relevant materials filed or that will be filed with the SEC in connection with the Proposed Business Combination as they become available because they will contain important information about General Fusion, SVAC and the Proposed Business Combination. Investors and security holders are able to obtain free copies of the Registration Statement, the Proxy Statement and all other relevant documents filed or that will be filed with the SEC by SVAC through the website maintained by the SEC at www.sec.gov. In addition, the documents filed by SVAC may be obtained free of charge from SVAC's website at https://sv-ac.com or by directing a request to Spring Valley Acquisition Corp. III, Attn: Corporate Secretary, 2100 McKinney Avenue, Suite 1675, Dallas, Texas 75201. The information contained on, or that may be accessed through, the websites referenced in this document is not incorporated by reference into, and is not a part of, this document.

Participants in the Solicitation

General Fusion, SVAC and their respective directors, executive officers and other members of management and employees may, under the rules of the SEC, be deemed to be participants in the solicitations of proxies from SVAC's shareholders in connection with the Proposed Business Combination. For more information about the names, affiliations and interests of SVAC's directors and executive officers, please refer to the Final Prospectus and the Registration Statement, Proxy Statement and other relevant materials filed or to be filed with the SEC in connection with the Proposed Business Combination when they become available. Additional information regarding the participants in the proxy solicitation and a description of their direct and indirect interests, which may, in some cases, be different than those of SVAC's shareholders generally, will be included in the Registration Statement and the Proxy Statement, when they become available. Shareholders, potential investors and other interested persons should read the Registration Statement and the Proxy Statement carefully, when they become available, before making any voting or investment decisions. You may obtain free copies of these documents from the sources indicated above.

No Offer or Solicitation

This document shall not constitute a "solicitation" as defined in Section 14 of the Securities Exchange Act of 1934, as amended. This document shall not constitute an offer to sell or exchange, the solicitation of an offer to buy or a recommendation to purchase, any securities, or a solicitation of any vote, consent or approval, nor shall there be any sale, issuance or transfer of securities in any jurisdiction in which such offer, solicitation or sale may be unlawful under the laws of such jurisdiction. No offering of securities in the Proposed Business Combination shall be made except by means of a prospectus meeting the requirements of the Securities Act of 1933, as amended, or an exemption therefrom.

Investor Relations Contact:

You can contact General Fusion's Investor Relations team by email at: investors@generalfusion.com.

If you are based in North America, you may also leave a toll-free voicemail at +1 (833) 717-1519. Callers outside North America can reach us at +1 (236) 253-6968.

Media Relations Contact:

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