Over the past several years, fusion power has undergone a remarkable transformation from a distant dream to an increasingly tangible and tantalizing technology. This shift has drawn investors off the sidelines, eager to capitalize on the potential of fusion to harness the nuclear reaction that powers the sun and generate nearly limitless energy here on Earth.

Source: techcrunch.com

The fusion industry has been driven by three significant advances: more powerful computer chips, more sophisticated AI, and powerful high-temperature superconducting magnets. These advancements have enabled the development of more sophisticated reactor designs, better simulations, and more complex control schemes.

Scientific Breakthroughs and Private Investment

At the end 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. This breakthrough marked a significant milestone, as it crossed what’s known as scientific breakeven. While it’s still a long way from commercial breakeven, where the reaction produces more than the entire facility consumes, this achievement proved the underlying science was sound.

Founders have built on this momentum in recent years, pushing the private fusion industry forward at a rapid pace. Several startups have raised over $100 million in committed capital from private investors, according to data provided to TechCrunch by FusionX.

Commonwealth Fusion Systems (CFS)

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 July, added $1 billion to its coffers, bringing its total raised to $3.94 billion, according to FusionX. CFS catapulted into the lead in 2021 with a $1.8 billion Series B.

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. The company says Sparc should reach scientific breakeven – also known as Q > 1 – sometime in 2027. 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.

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 Massachusetts-based CFS expects to have Sparc operational in late 2026 or early 2027. Later this decade, the company says it will begin 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 buy half its output.

Helion

Helion has the most aggressive timeline among fusion startups, planning to produce electricity from its reactor in 2028. Its first customer? Microsoft. The company uses a type of reactor called a field-reversed configuration, where magnets surround a reaction chamber that looks like an hourglass with a bulge at the point where the two sides come together.

Helion 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. Altogether, Helion has raised $3.2 billion in committed capital, according to FusionX. Investors include Sam Altman, SoftBank Vision Fund 2, Reid Hoffman, KKR, BlackRock, Peter Thiel’s Mithril Capital Management, and Capricorn Investment Group.

Other Notable Fusion Startups

Other notable fusion startups include TAE Technologies, Pacific Fusion, and Proxima Fusion. TAE Technologies, founded in 1998, has raised over $1.65 billion in committed capital. The company uses 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.

Pacific Fusion burst out of the gate with a Series A that topped $1 billion, the startup has told TechCrunch. The company will use inertial confinement to achieve fusion, but instead of lasers compressing the fuel, it will use coordinated electromagnetic pulses. Proxima Fusion, led by CEO Eric Lander, the scientist who led the Human Genome Project, and chief scientist Will Regan, has raised more than $682.9 million across rounds, according to FusionX.