Any merger startup that has raised over $100 million

In the last few years, fusion energy has stopped being a joke – always in a decade! — to an increasingly tangible and tempting technology that has sidelined investors.

The technology may be difficult to master and expensive to build today, but fusion could harness the nuclear reaction that powers the sun to produce almost limitless energy here on Earth. If startups manage to complete commercially viable fusion plants, they have the potential to upend trillion-dollar markets.

The bullish wave driving the fusion industry is fueled by three advances: more powerful computer chips, more sophisticated artificial intelligence and powerful, high-temperature superconducting magnets. Together, they helped develop more sophisticated reactor designs, better simulations, and more complex control schemes.

It doesn’t hurt that in late 2022, a U.S. Department of Energy laboratory announced that it had produced a controlled fusion reaction that produced more power than the lasers imparted to the fuel pellet. The experiment exceeded the so-called scientific break-even point, and although it is still a long way to the commercial break-even point, where the reaction produces more than the entire facility consumes, it was a long-awaited step that proved that the scientific basis was sound.

The founders have capitalized on this momentum in recent years, pushing the private fusion industry forward at a rapid pace. According to the Fusion Industry Association, Fusion startups have raised $7.1 billion to date, most of which has gone to a few companies.

Commonwealth Fusion Systems

Thanks to its $1.8 billion Series B, Commonwealth Fusion Systems catapulted itself into pole position in 2021. Since then, the company has been quiet about fundraising (no surprise), but it has been hard at work in Massachusetts building Sparc, its first one-of-a-kind a type of power plant designed to produce energy at a level that is called “commercially significant”.

The Sparc reactor uses a tokamak design that resembles a doughnut. The D-shaped cross-section is wound with high-temperature superconducting tape, which, when energized, generates a strong magnetic field that will contain and compress the superheated plasma. In Sparc’s commercial-scale successor, Arc, the heat from the reaction is converted to steam to drive 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.

Backed by Breakthrough Energy Ventures, The Engine, Bill Gates and others, Devens, Mass.-based CFS expects Arc to be operational in the early 2030s.

General merger

General Fusion has raised $440.53 million in its third decade, according to PitchBook. The Richmond, British Columbia-based company was founded in 2002 by physicist Michel Laberge, who wanted to prove a different approach to nuclear fusion, known as magnetic target fusion (MTF).

In the General Fusion reactor, a wall of liquid metal surrounds the chamber into which plasma is injected. Pistons surrounding the wall push it inward, compressing the plasma inside and causing a thermonuclear reaction. The resulting neutrons heat the liquid metal, which can circulate through a heat exchanger to produce steam to turn a turbine.

The company is currently building its first LM26 demonstration plant, which it hopes to reach scientific break-even by 2026. Investors include Jeff Bezos, Temasek, BDC Capital and Chrysalix Venture Capital.

Helion

Of all the merger startups, Helion has the most aggressive timeline. The company plans to produce electricity from its reactor in 2028. First customer? Microsoft.

Helion uses a type of reactor called a reverse-field configuration, in which magnets surround a reaction chamber that looks like an hourglass with a bulge where the two sides meet. At both ends, the hourglasses spin plasma into donut shapes that are ejected toward each other at speeds of more than 1 million miles per hour. When they collide in the middle, additional magnets help trigger fusion. When fusion occurs, it strengthens the plasma’s own magnetic field, which induces an electric current inside the reactor’s magnetic coils. The electricity is then taken directly from the machine.

Everett, Washington-based Helion raised $607.64 million, according to PitchBook. Investors include Sam Altman, Reid Hoffman, KKR, BlackRock, Peter Thiel’s Mithril Capital Management and Capricorn Investment Group.

TAE

Founded in 1998, TAE (formerly known as Tri Alpha Energy) was spun out of the University of California, Irvine by Norman Rostoker. It uses a reverse-field configuration, but with a twist: After two shots of plasma collide in the center of the reactor, the company bombards the plasma with particle beams to keep it in a cigar shape. This improves the stability of the plasma, allowing more time for fusion to occur and for more heat to be extracted to spin the turbine.

TAE has raised $1.32 billion, according to PitchBook. Investors include Alphabet, Chevron Technology Ventures and Venrock.

Zap Energy

Zap Energy does not use high-temperature superconducting magnets or super-powerful lasers to keep the plasma confined. On the contrary, it hits the plasma (get it?) with an electric current, which then generates its own magnetic field. The magnetic field compresses the plasma by about 1 millimeter, at which point ignition occurs. Neutrons released in a thermonuclear reaction bombard the liquid metal jacket surrounding the reactor, heating it. The liquid metal is then passed through a heat exchanger, where it produces steam that powers a turbine.

Like Helion, Zap Energy is based in Everett, Washington, and has raised $327 million, according to PitchBook. Sponsors include Bill Gates’ disruptive energy ventures, DCVC, Lowercarbon, Energy Impact Partners, Chevron Technology Ventures and Bill Gates Angel.

Tokamak energy

Tokamak Energy takes the typical tokamak design – the donut shape – and squishes it, reducing its proportions to the point where the outer boundaries begin to resemble a sphere. Like many other tokamak-based startups, the company uses high-temperature superconducting magnets (a variety of rare earth copper oxide, or REBCO). Because its design is more compact than a traditional tokamak, it requires fewer magnets, which should reduce costs.

The startup’s ST40 prototype from Oxfordshire, UK, which looks like a large, steampunk Fabergé egg, generated an ultra-hot plasma of 100 million degrees C in 2022. The next generation, Demo 4, is currently under construction and is intended to test magnets company in “scenarios relevant to fusion power plants.” According to PitchBook, Tokamak Energy has raised $285.65 million from investors including Future Planet Capital, In-Q-Tel, Midven and Capri-Sun founder Hans-Peter Wild.

First Light

Unlike many other fusion startups, First Light does not use magnets to generate the conditions necessary for fusion. Instead, an approach known as inertial confinement was used, in which fusion fuel pellets are compressed until they ignite.

But even then, First Light does not adhere to orthodoxy. Most inertial confinement trials use lasers to do the dirty work, following the lead of the National Ignition Facility, which conducted a groundbreaking experiment in 2022. Rather, First Light fires a projectile at a target using a two-stage gun; the first stage uses gunpowder to fire a plastic piston that compresses hydrogen to 145,000 psi, which then fires the projectile. The goal is to increase the force of the impact so as to compress the fuel to the ignition point.

Oxfordshire, UK-based First Light has raised $179.94 million from investors including Invesco, IP Group and Tencent.

Marvel merger

Marvel Fusion uses the inertial confinement method, which is the same basic technique that the National Ignition Facility used to prove that controlled nuclear fusion reactions can produce more energy than is needed to run them. Marvel fires powerful lasers at a target embedded with silicon nanostructures, which cascade under the bombardment, compressing the fuel to the ignition point. Since the shield is made of silicon, its production should be relatively simple, based on decades of experience in the semiconductor manufacturing industry.

Closed inertial fusion startup is building a demonstration facility in partnership with Colorado State University that is expected to be operational by 2027. Munich-based Marvel has raised a total of $109.3 million from investors including b2venture, Deutsche Telekom, Earlybird, HV Capital, and Taavet Hinrikus and Albert Wenger as Angels.

Xcimer

While nothing about fusion can be described as simple, Xcimer takes a relatively simple approach: follow the science behind the groundbreaking net-positive experiment at the National Ignition Facility and redesign the technology that underpins it from the ground up. The Colorado-based startup aims to develop a 10-megajoule laser system, five times more powerful than the NIF system that made history. Walls of molten salt surround the reaction chamber, absorbing heat and protecting the first solid wall from damage.

Founded in January 2022, Xcimer has already raised $109 million from investors including Hedosophia, Breakthrough Energy Ventures, Emerson Collective, Gigascale Capital and Lowercarbon Capital, according to PitchBook.