Almost $3B invested into fusion companies in 2024, says Cleantech Group

SAN FRANCISCO, CA — March 19, 2025 — A boom in power-hungry AI systems is rekindling interest in fusion technology, with investments more than tripling over the past year, and attracting tech superstars such as OpenAI’s Sam Altman, Google Deepmind’s Mustafa Suleyman and Google’s Eric Schmidt, says Cleantech Group.

Last year, investors committed almost $3B in venture funding to fusion technologies. This includes Neo Fusion’s raise of $1.3B and Pacific Fusion’s milestone-based $900M Series A financing round. Publicly disclosed funding for nuclear energy technologies hit a five-year high, exceeding a 2021 peak.

2024 saw a variety of fusion reactors receive funding. Neo Fusion and Tokamak Energy raised funds to support their tokamak model. Companies advancing stellarators, pulsed magnetic inertial, z pinch, and inertial confinement systems also saw significant growth.

“Unique and complex reactor systems that previously would have been too difficult or uneconomical to pursue are seeing growing interest due to the advances in computing, 3D printing, precision manufacturing, advanced control systems, and higher-powered magnets,” said Zainab Gilani, Cleantech Group Associate, Energy & Power.

“While many of these emerging technologies still have critical milestones they need to achieve to prove out their concepts, their claims of attaining faster speeds-to-scale or better plasma stability are attracting the attention of investors interested in funding multiple pathways to commercialize fusion,” she added.

While the U.S. leads in advancing a variety of fusion approaches, China’s public and private sectors are still focusing heavily on advancing tokamaks leveraging high temperature superconducting systems with limited diversification into other models thus far.

Other key findings:

• New breed of investors. Helion, which already has a power purchase agreement with Microsoft for 2028, earlier this year closed a $425M Series F funding round, with AI pioneer Altman among its backers. Pacific Fusion raised $900M in commitments from investors such as Google and LinkedIn. Corporate backers for fusion include automotive giants Toyota and Honda, oil majors Shell and Chevron, in addition to expected moonshot investors Lowercarbon Capital and Breakthrough Energy Ventures.
• Focused on milestones. New approaches to fusion are reaching critical milestones and unlocking more financing. These milestones can include producing stable plasmas, achieving critical temperatures, and eventually will include reaching net energy gain.  In recent months, OpenStar Technologies and General Fusion achieved first plasmas and will continue to build off the success from these milestones.  Additionally, in 2024 Zap Energy achieved 37M° C on a smaller Z-pinch machine and was also able to raise $130M funding.
• Attraction of large numbers. The U.S. Energy Information Administration (EIA) says global energy demand — driven by population growth as much as key sectors such as data processing — has the potential to increase 50% by 2050 while the IEA estimates that global energy demand could double by 2050.
• Stellarators are among the technologies gaining traction. Several companies have elected to pursue stellarators, fusion devices that involve twisted coils of magnets to confine plasmas. The Wendelstein 7-X, built by the Max Planck Institute for Plasma Physics in Germany, and Japan’s Large Helical Device, the world’s second largest stellarator, have been a catalyst in popularizing the technology. In 2023, at least 7 stellarator companies received investments.

To learn more, register for our complimentary webinar, Commercializing Fusion, on April 8^th.

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