Tech energy news — fusion power went from the industry’s favourite punchline to an investor magnet, and the money is now piling up: Commonwealth Fusion Systems alone has raised nearly $3 billion. Here is every private fusion startup that has raised over $100 million, what approach each is betting on, and who’s backing them.
By Maplestime Business Desk | Toronto, Ontario | September 19, 2026
Sources: TechCrunch, PitchBook, Wikipedia | Last updated: September 19, 2026
Quick Facts
- Commonwealth Fusion Systems leads the pack with nearly $3 billion raised — about a third of all private fusion capital
- Pacific Fusion launched with a $900 million Series A, one of the largest first rounds in energy startup history
- Helion has the most aggressive timeline: electricity from its reactor in 2028, with Microsoft as its first customer
- Canada’s own General Fusion (Richmond, B.C.) has raised $462.53 million — and had a rough 2025
- Twelve startups have now crossed the $100 million mark, backed by names like Bill Gates, Jeff Bezos, Sam Altman, Google, Chevron, and KKR
- The industry got its scientific credibility moment in late 2022, when a U.S. Department of Energy lab crossed scientific breakeven
Why Fusion Stopped Being a Joke
Over the last several years, fusion power has gone from the butt of jokes — always a decade away! — to an increasingly tangible and tantalizing technology that has drawn investors off the sidelines.
The technology is hard to master and expensive to build today, but fusion promises to harness the nuclear reaction that powers the sun to generate nearly limitless energy on Earth. If startups can complete commercially viable fusion power plants, they have the potential to upend trillion-dollar markets.
The bullish wave has been driven by three advances: more powerful computer chips, more sophisticated AI, and powerful high-temperature superconducting magnets. Together they’ve delivered better reactor designs, better simulations, and more complex control schemes.
It doesn’t hurt that, at the end of 2022, a U.S. Department of Energy lab announced it had produced a controlled fusion reaction that put out more power than the lasers had imparted to the fuel pellet — crossing scientific breakeven. It’s still a long way from commercial breakeven, where the reaction produces more than the entire facility consumes, but it was a long-awaited step proving the underlying science was sound.
Founders have been building on that momentum ever since, pushing the private fusion industry forward at a rapid pace.
Commonwealth Fusion Systems — ~$3 Billion
Commonwealth Fusion Systems (CFS) has raised about a third of all private capital invested in fusion companies to date. Its latest round, which closed in August, added $863 million to its coffers, bringing its total near $3 billion.
CFS’s Series B2 came four years after its $1.8 billion Series B, which catapulted the company into pole position. Since then, the startup has been hard at work in Massachusetts building Sparc, its first-of-a-kind power plant intended to produce power at what it calls “commercially relevant” levels.
Sparc’s reactor is a tokamak — a doughnut shape — with a D-shaped cross section wound with high-temperature superconducting tape that generates a powerful magnetic field to contain and compress superheated plasma. CFS designed its magnets with MIT, where co-founder and CEO Bob Mumgaard researched fusion reactor designs and high-temperature superconductors.
The Massachusetts-based CFS expects Sparc to be operational in late 2026 or early 2027. Later this decade, construction begins on Arc, its commercial power plant producing 400 megawatts of electricity near Richmond, Virginia — and Google has agreed to buy half its output.
Backers include Breakthrough Energy Ventures, The Engine, Bill Gates, and others.
TAE — $1.79 Billion
Founded in 1998, TAE Technologies (formerly Tri Alpha Energy) was spun out of the University of California, Irvine by Norman Rostoker. It uses a field-reversed configuration with a twist: after two plasma shots collide in the middle of the reactor, the company bombards the plasma with particle beams to keep it spinning in a cigar shape, improving plasma stability for more fusion time and more extractable heat.
The company raised $150 million in June from existing investors including Google, Chevron, and New Enterprise. TAE has raised $1.79 billion in total, according to PitchBook.
Helion — $1.03 Billion
Of all fusion startups, Helion has the most aggressive timeline: electricity from its reactor in 2028. Its first customer? Microsoft.
The Everett, Washington company uses a field-reversed configuration where magnets surround an hourglass-shaped reaction chamber. At each end, plasma is spun into doughnut shapes and shot toward each other at more than 1 million mph. When they collide, magnets help induce fusion, which boosts the plasma’s own magnetic field, inducing an electrical current harvested directly from the machine.
Helion raised $425 million in January 2025, around the same time it turned on Polaris, a prototype reactor. It has raised $1.03 billion per PitchBook. Investors include Sam Altman, Reid Hoffman, KKR, BlackRock, Peter Thiel’s Mithril Capital Management, and Capricorn Investment Group.
Pacific Fusion — $900 Million
Pacific Fusion burst out of the gate with a $900 million Series A — a whopping sum even among well-funded fusion startups. The company uses inertial confinement, but instead of lasers compressing the fuel, it uses coordinated electromagnetic pulses. The trick is timing: all 156 impedance-matched Marx generators need to produce 2 terawatts for 100 nanoseconds, converging simultaneously on the target.
The company is led by CEO Eric Lander, the scientist who led the Human Genome Project, and president Will Regan. The funding comes in tranches tied to milestone achievements — an approach common in biotech.
Related: NATO Backs Canadian Defence Tech With Nearly $1B in New Funding
Shine Technologies — $778 Million
Shine Technologies is taking the cautious — and possibly pragmatic — route. Selling electrons from a fusion power plant is years off, so it started by selling neutron testing and medical isotopes, and more recently has been developing a way to recycle radioactive waste. Shine hasn’t picked an approach for a future fusion reactor, instead building the skills it will need when the time comes.
The company has raised $778 million total per PitchBook. Investors include Energy Ventures Group, Koch Disruptive Technologies, Nucleation Capital, and the Wisconsin Alumni Research Foundation.
General Fusion — $462.53 Million
Now in its third decade, General Fusion has raised $462.53 million per PitchBook. The Richmond, British Columbia-based company was founded in 2002 by physicist Michel Laberge to prove magnetized target fusion (MTF). Investors include Jeff Bezos, Temasek, BDC Capital, and Chrysalix Venture Capital.
In General Fusion’s reactor, a liquid metal wall surrounds a chamber where plasma is injected. Pistons push the wall inward, compressing the plasma and sparking fusion. Neutrons heat the liquid metal, which circulates through a heat exchanger to generate steam for a turbine.
General Fusion hit a rough patch in spring 2025. The company ran short of cash while building LM26, its latest device it hoped would hit breakeven in 2026. Just days after hitting a key milestone, it laid off 25% of its staff. CEO Greg Twinney penned an open letter pleading for funding. In August, investors delivered somewhat — injecting $22 million in a pay-to-play round one investor called “the least amount of capital possible” to keep General Fusion afloat.
Tokamak Energy — $336 Million
Tokamak Energy takes the usual tokamak doughnut design and squeezes it, reducing its aspect ratio until the outer bounds start resembling a sphere. Like many tokamak startups, it uses high-temperature superconducting magnets (the rare earth barium copper oxide, or REBCO, variety). The compact design needs fewer magnets, which should reduce costs.
The Oxfordshire, U.K. startup’s ST40 prototype — looking like a large steampunk Fabergé egg — generated an ultra-hot 100-million-degree-C plasma in 2022. Its next generation, Demo 4, is under construction to test the magnets in “fusion power plant-relevant scenarios.” Tokamak Energy raised $125 million in November 2024 to continue reactor design and expand its magnet business.
Total raised: $336 million from Future Planet Capital, In-Q-Tel, Midven, and Capri-Sun founder Hans-Peter Wild, per PitchBook.
Zap Energy — $327 Million
Zap Energy doesn’t use high-temperature superconducting magnets or super-powerful lasers. It zaps the plasma (get it?) with an electric current, which generates its own magnetic field, compressing the plasma about 1 millimetre until ignition occurs. Neutrons bombard a liquid metal blanket, heating it; the metal cycles through a heat exchanger to produce steam for a turbine.
Like Helion, Zap Energy is based in Everett, Washington, and has raised $327 million per PitchBook. Backers include Bill Gates’ Breakthrough Energy Ventures, DCVC, Lowercarbon, Energy Impact Partners, Chevron Technology Ventures, and Bill Gates as an angel.
Proxima Fusion — €185+ Million
Most investors have favoured tokamaks or inertial confinement, but stellarators have shown great promise in experiments like Germany’s Wendelstein 7-X. Proxima Fusion is bucking the trend, attracting a €130 million Series A that brings its total raised to more than €185 million. Investors include Balderton Capital and Cherry Ventures.
Stellarators confine plasma in a ring using powerful magnets — but with a literal twist, shaping the ring to accommodate the plasma’s quirks for longer stability and better odds of fusion reactions.
Marvel Fusion — $161 Million
Marvel Fusion follows the inertial confinement approach — the same basic technique the National Ignition Facility used to prove controlled fusion could produce net-positive energy. Marvel fires powerful lasers at a target embedded with silicon nanostructures that cascade under bombardment, compressing fuel to ignition. The silicon target should be relatively simple to manufacture, leaning on the semiconductor industry’s decades of experience.
The Munich-based startup is building a demonstration facility with Colorado State University, expected operational by 2027. It has raised $161 million from b2venture, Deutsche Telekom, Earlybird, HV Capital, and angels Taavet Hinrikus and Albert Wenger.
First Light — $140 Million
First Light dropped its pursuit of fusion power in March 2025, pivoting to become a technology supplier to fusion startups and other companies. It had previously followed inertial confinement, compressing fusion fuel pellets until ignition.
The Oxfordshire, U.K. company has raised $140 million per PitchBook from Invesco, IP Group, and Tencent.
Xcimer — $109 Million
Xcimer takes a relatively straightforward approach: follow the basic science behind the National Ignition Facility’s net-positive breakthrough and redesign the underlying technology from the ground up. The Colorado-based startup is aiming for a 10-megajoule laser system — five times more powerful than NIF’s history-making setup. Molten salt walls surround the reaction chamber, absorbing heat and protecting the first solid wall.
Founded in January 2022, Xcimer has raised $109 million per PitchBook from Hedosophia, Breakthrough Energy Ventures, Emerson Collective, Gigascale Capital, and Lowercarbon Capital.
Maplestime will provide updates on fusion energy and clean technology as announcements are made.
Have a tip about fusion startups? Email [email protected]
Have a correction? Email [email protected]
Which fusion startup actually gets to commercial power first — and will investors still be patient if breakeven keeps slipping? Tell us in the comments. And share this with every Canadian watching the race for limitless energy.
