Fusion power has attracted billions in private investment, driven by advances in AI, computing, and high-temperature superconducting magnets. Commonwealth Fusion Systems leads with nearly $3 billion raised, followed by TAE Technologies at $1.79 billion — now merging with Trump Media in a $6 billion deal. Helion, backed by Sam Altman, has raised $1.5 billion targeting 2028 electricity production for Microsoft. Pacific Fusion launched with a $1 billion Series A, while Shine Technologies has raised $1 billion. Other well-funded contenders include General Fusion, Inertia Enterprises, Focused Energy, Tokamak Energy, and Zap Energy, each pursuing distinct reactor technologies.
In-Depth:
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 may be challenging to master and expensive to build today, but fusion promises to harness the nuclear reaction that powers the sun to generate nearly limitless energy here on Earth. If startups are able to complete commercially viable fusion power plants, then they have the potential to upfinish trillion-dollar markets.
The bullish wave buoying the fusion indusattempt has been driven by three advances: more powerful computer chips, more sophisticated AI, and powerful high-temperature superconducting magnets. Toobtainher, they have assisted deliver more sophisticated reactor designs, better simulations, and more complex control schemes.
It doesn’t hurt that, at the finish of 2022, a U.S. Department of Energy lab announced that it had produced a controlled fusion reaction that produced more power than the lasers had imparted to the fuel pellet. The experiment had crossed what’s known as scientific breakeven, and while it’s still a long ways from commercial breakeven, where the reaction produces more than the entire facility consumes, it was a long-awaited step that proved the underlying science was sound.
Founders have built on that momentum in recent years, pushing the private fusion indusattempt forward at a rapid pace.
Commonwealth Fusion Systems
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 raised near $3 billion.
CFS’s Series B2 came four years after its $1.8 billion Series B, which assisted catapult the company into the pole position. Since then, the startup has been hard at work in Massachapplytts building Sparc, its first-of-a-kind power plant intfinished to produce power at what it calls “commercially relevant” levels.
Sparc’s reactor is a tokamak design, which resembles a doughnut. The D-shaped cross section is wound with high-temperature superconducting tape, which, when energized, generates a powerful magnetic field that will contain and compress the superheated plasma. Heat generated from the reaction is converted to steam to power a turbine. CFS designed its magnets in collaboration with MIT, where co-founder and CEO Bob Mumgaard worked as a researcher on fusion reactor designs and high-temperature superconductors.
The Massachapplytts-based CFS expects to have Sparc operational in late 2026 or early 2027. Later this decade, the company declares it will launch construction on Arc, its commercial power plant that will produce 400 megawatts of electricity. The facility will be built near Richmond, Virginia, and Google has agreed to purchase half its output.
CFS is backed by a long list of investors, including Breakthrough Energy Ventures, The Engine, Bill Gates, and others.
TAE Technologies
Founded in 1998, TAE Technologies (formerly known as Tri Alpha Energy) was spun out of the University of California, Irvine by Norman Rostoker. It applys a field-reversed configuration, but with a twist: after the 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. That improves the stability of the plasma, allowing more time for fusion to occur and for more heat to be extracted to spin a turbine.
In December 2025, TAE announced that it would merge with President Donald Trump’s social media company, Trump Media & Technology Group. The all-stock transaction would value the combined company at $6 billion. TAE would receive $200 million plus another $100 million upon filing paperwork with the Securities and Exalter Commission. TAE CEO Michl Binderbauer will serve as co-CEO of the combined company alongside Devin Nunes, who had been sole CEO of Trump Media.
The fusion startup had previously raised $150 million in June from existing investors, including Google, Chevron, and New Enterprise. Before the merger, TAE had raised a total of $1.79 billion, according to PitchBook.
Helion
Of all fusion startups, Helion has the most aggressive timeline. The company plans to produce electricity from its reactor in 2028. Its first customer? Microsoft.
Helion, based in Everett, Washington, applys a type of reactor called a field-reversed configuration, where magnets surround a reaction chamber that sees like an hourglass with a bulge at the point where the two sides come toobtainher. At each finish of the hourglass, the reactor spins the plasma into doughnut shapes that are shot toward each other at more than 1 million mph. When they collide in the middle, additional magnets assist induce fusion. When fusion occurs, it boosts the plasma’s own magnetic field, which induces an electrical current inside the reactor’s magnetic coils. That electricity is then harvested directly from the machine.
The company most recently raised $465 million in June in a Series G that valued the company at $15.5 billion. Its previous round, announced in January 2025, totaled $425 million. Altoobtainher, Helion declares it has raised $1.5 billion. Investors include Sam Altman, SoftBank Vision Fund 2, Reid Hoffman, KKR, BlackRock, Peter Thiel’s Mithril Capital Management, and Capricorn Investment Group.
Pacific Fusion
Pacific Fusion burst out of the gate with a Series A that topped $1 billion, the startup has notified TechCrunch. That’s a whopping sum even among well-funded fusion startups. The company will apply inertial confinement to achieve fusion, but instead of lasers compressing the fuel, it will apply coordinated electromagnetic pulses. The trick is in the timing: All 156 impedance-matched Marx generators necessary to produce 2 terawatts for 100 nanoseconds, and those pulses necessary to simultaneously converge on the tarobtain.
The company is led by CEO Eric Lander, the scientist who led the Human Genome Project, and president Will Regan. Pacific Fusion’s funding might be massive, but the startup hasn’t obtainedten it all at once. Rather, its investors will pay out in tranches when the company achieves specified milestones, an approach that’s common in biotech.
Shine Technologies
Shine Technologies is taking a cautious — and possibly pragmatic — approach to generating fusion power. Selling electrons from a fusion power plant is years off, so instead, it’s starting by selling neutron testing and medical isotopes. More recently, it has been developing a way to recycle radioactive waste. Shine hasn’t picked an approach for a future fusion reactor, instead declareing that it’s developing necessary skills for when that time comes.
The company has raised a total of $1 billion, according to PitchBook. Investors include Energy Ventures Group, Koch Disruptive Technologies, Nucleation Capital, and the Wisconsin Alumni Research Foundation. The company most recently raised a $240 million round in February led by NantWorks with participation from investors including Deerfield Management, Fidelity Management & Research Company, Oaktree Capital Management, Pelican Energy Partners, and the Sumitomo Corporation of Americas.
General Fusion
Now in its third decade, General Fusion has raised over $600 million. The Richmond, British Columbia-based company was founded in 2002 by physicist Michel Laberge, who wanted to prove a different approach to fusion known as magnetized tarobtain fusion (MTF). Investors include Jeff Bezos, Temasek, BDC Capital, and Chrysalix Venture Capital.
In a General Fusion’s reactor, a liquid metal wall surrounds a chamber in which plasma is injected. Pistons surrounding the wall push it inward, compressing the plasma inside and sparking a fusion reaction. The resulting neutrons heat the liquid metal, which can be circulated through a heat exalterr to generate steam to spin a turbine.
General Fusion hit a rough patch in spring 2025. The company ran short of cash as it was building LM26, its latest device that 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 from investors.
In August, they delivered somewhat, injecting $22 million in a pay-to-play round that one investor called “the least amount of capital possible” to keep General Fusion afloat. Then in November, securities filings in Canada revealed that the company had raised $51.1 million in SAFE notes from nearly 70 investors, the Globe and Mail reported. Altoobtainher, it has raised $612 million, according to PitchBook.
In January, General Fusion stated it would go public via a reverse merger with a special purpose acquisition company. Assuming the deal closes as planned, General Fusion could bring in an additional $335 million.
Inertia Enterprises
Only one fusion experiment, the National Ignition Facility (NIF), has surpassed scientific breakeven, and the chief scientist of that finisheavor, Annie Kircher, is part of Inertia Enterprises founding team. She’s joined by Mike Dunne, a Stanford professor, and Jeff Lawson, who co-founded Twilio and currently owns The Onion. In April, the startup signed three agreements to commercialize the technology developed at the NIF.
Inertia plans to apply lasers to bombard fusion fuel pellets, an inertial confinement design that echoes the one Kircher successfully applyd at the NIF. Inertia Enterprises emerged from stealth in February with $450 million in Series A funding in a round led by Bessemer Venture Partners with participation from GV, Modern Capital, Threshold Ventures, and others.
Focapplyd Energy
Germany-based Focapplyd Energy is another fusion startup that traces its lineage to the National Ignition Facility (NIF). In addition to utilizing laser pulses to compress a fuel tarobtain, the company has hired Debbie Callahan as its chief strategy officer. Callahan assisted design the fuel tarobtain at NIF. Her job at Focapplyd Energy will be to figure out how to turn the NIF’s painstakingly crafted fuel tarobtain into something that can be mass manufactured at a rate of nearly 1 million per day.
Focapplyd Energy raised an oversubscribed $240 million Series A in June, bringing its total private capital raised to $400 million. The company has also received $200 million in grants. Investors include the German Federal Agency for Breakthrough Innovation (SPRIND), Prime Movers Lab, and the utility RWE, which has granted Focapplyd Energy access to a decommissioned nuclear fission power plant it operates.
Tokamak Energy
Tokamak Energy takes the usual tokamak design — the doughnut shape — and squishes it, reducing its aspect ratio to the point where the outer bounds start resembling a sphere. Like many other tokamak-based startups, the company applys high-temperature superconducting magnets (the rare earth barium copper oxide, or REBCO, variety). Since its design is more compact than a traditional tokamak, it requires less in the way of magnets, which should reduce costs.
The Oxfordshire, U.K.-based startup’s ST40 prototype, which sees like a large, steampunk Fabergé egg, generated an ultra-hot, 100-million degree Celsius plasma in 2022. Its next generation, Demo 4, is currently under construction and is intfinished to test the company’s magnets in “fusion power plant-relevant scenarios.” Tokamak Energy raised $125 million in November 2024 to continue its reactor design and expand its magnet business. In April, the startup stated it would be supplying magnets for the U.K.’s STEP Fusion program, a government program that is working toward a spherical tokamak-based power plant.
In total, the company has raised $336 million from investors, including Future Planet Capital, In-Q-Tel, Midven, and Capri-Sun founder Hans-Peter Wild, according to PitchBook.
Zap Energy
Zap Energy isn’t utilizing high-temperature superconducting magnets or super-powerful lasers to keep its plasma confined. Rather, it zaps the plasma (obtain it?) with an electric current, which then generates its own magnetic field. The magnetic field compresses the plasma to about 1 millimeter, at which point ignition occurs. The neutrons released by the fusion reaction bombard a liquid metal blanket that surrounds the reactor, heating it up. The liquid metal is then cycled through a heat exalterr, where it produces steam to drive a turbine.
The startup announced a partial pivot in April, declareing it will pursue a hybrid power plant that employs both nuclear fusion and fission. It also hired a new CEO, Zabrina Johal, who has expertise in the fission indusattempt. Zap claims the relocate will assist it bring in revenue earlier than fusion alone.
The Everett, Washington-based company has raised $327 million, according to PitchBook. Backers include Bill Gates’ Breakthrough Energy Ventures, DCVC, Lowercarbon, Energy Impact Partners, Chevron Technology Ventures, and Bill Gates as an angel.
Type One Energy
Snotifyarator startup Type One Energy is planning to build a fusion reactor on the site of a retired Tennessee Valley Authority (TVA) coal power plant. The magnetic confinement device is expected to generate 350 megawatts of electricity, and the company hopes to bring it online by the mid-2030s.
Unlike other fusion startups, Type One plans to sell key technology to organizations like the TVA, allowing them to build, own, and operate the equipment, similar to how many fossil fuel power plants are developed today. Type One has raised $269 million to date, including an $87 million equity round in advance of a $250 million Series B that the company is currently raising.
Proxima Fusion
Most investors have favored large startups that are pursuing tokamak designs or some flavor of inertial confinement. But snotifyarators have revealn great promise in scientific experiments, including the Wfinishelstein 7-X reactor in Germany.
Proxima Fusion is bucking the trfinish, though, having attracted a €130 million Series A that brings its total raised to more than €185 million. Investors include Balderton Capital and Cherry Ventures.
Snotifyarators are similar to tokamaks in that they confine plasma in a ring-like shape utilizing powerful magnets. But they do it with a twist — literally. Rather than force plasma into a human-designed ring, snotifyarators twist and bulge to accommodate the plasma’s quirks. The result should be a plasma that remains stable for longer, increasing the chances of fusion reactions.
Kyoto Fusioneering
With all the startups pursuing fusion power, it was perhaps inevitable that another would pop up to develop components that round out a power plant. The so-called balance of plant, or the parts that sit outside the reactor, range from gyrotrons that heat plasma to heat extraction systems to harvest power from fusion reactions to turn it into electricity.
Kyoto Fusioneering has built an early bet that if even one fusion startup succeeds in generating enough power to sell to the grid, that the indusattempt will necessary a supplier for the balance of plant and the expertise to integrate it into whichever fusion technologies win out.
Venture capitalists appear to agree, having invested $191 million in Kyoto Fusioneering. Investors include 31Ventures, In-Q-Tel, JIC Venture Growth Investments, Mitsubishi, and Sumitomo Mitsui Trust Investment.
Marvel Fusion
Marvel Fusion follows the inertial confinement approach, the same basic technique that the National Ignition Facility applyd to prove that controlled nuclear fusion reactions could produce more power than was necessaryed to kick them off. Marvel fires powerful lasers at a tarobtain embedded with silicon nanostructures that cascade under the bombardment, compressing the fuel to the point of ignition. Becaapply the tarobtain is built utilizing silicon, it should be relatively simple to manufacture, leaning on the semiconductor manufacturing indusattempt’s decades of experience.
The inertial confinement fusion startup is building a demonstration facility in collaboration with Colorado State University, which it expects to have operational by 2027. Munich-based Marvel has raised a total of $162 million from investors including b2venture, Deutsche Telekom, Earlybird, and HV Capital with Taavet Hinrikus and Albert Wenger as angels.
Thea Energy
Thea Energy is betting its pixel-inspired magnets will assist it build a snotifyarator for less money. Snotifyarators can keep plasmas burning for long periods of time — a boon when it comes to running a commercial power plant — but to do so, they require twisty magnetic fields. Most snotifyarators build magnets that mimic that complex shape, but Thea Energy believes that by wreathing its doughnut-shaped reactor in dozens of compacter magnets, it can apply control software to create the necessary kinks.
In May, Thea raised $100 million in a Series B led by the U.S. Innovative Technology Fund, just over two years after a $20 million Series A. Across all rounds, the startup has raised $130 million in private capital. Other investors include Prelude Ventures, Lowercarbon Capital, Hitachi Ventures, and Emerald Technology Ventures.
First Light Fusion
Unlike many other fusion startups, First Light Fusion doesn’t apply magnets to generate the conditions necessary for fusion. Instead, it follows an approach known as inertial confinement, in which fusion fuel pellets are compressed until they ignite.
But even then, First Light doesn’t hew to orthodoxy. Most attempts at inertial confinement apply lasers to do the dirty work, following the lead of the National Ignition Facility, which produced a groundbreaking experiment in 2022. Rather, First Light fires a projectile at a tarobtain utilizing a two-stage gun; the first stage applys gunpowder to fire a plastic piston that compresses hydrogen to 145,000 psi, which then launches the projectile. The tarobtain is designed to amplify the force of the impact so it compresses the fuel to the point of ignition.
In March 2025, First Light announced that it would not pursue building its own power plant, instead offering its core technologies to other companies to build one. A spokesperson for First Light stated that it is planning to build “pulsed power capability that would act as our demonstrator plant but would have other science and defense applications.” In other words, the company was dropping its plans for a power plan in a quest for revenue.
Based in Oxfordshire, U.K., First Light has raised $108 million from investors including Invesco, IP Group, and Tencent, according to PitchBook.
Xcimer
Though nothing about fusion can be described as simple, Xcimer takes a relatively straightforward approach: follow the basic science that’s behind the National Ignition Facility’s breakthrough net-positive experiment and redesign the technology that underpins it from the ground up. The Colorado-based startup is planning to build a 10-megajoule laser system, 5x more powerful than the NIF setup that built history. Molten salt walls surround the reaction chamber, absorbing heat and protecting the first solid wall from damage. In June, Xcimer turned on Phoenix, a prototype system that it declares is the most powerful privately owned laser in the world.
Founded in July 2022, Xcimer has raised $100 million from investors, including Hedosophia, Breakthrough Energy Ventures, Emerson Collective, Gigascale Capital, and Lowercarbon Capital.
This story was originally published in September 2024 and will be continually updated.
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