17 Fusion Startups That Have Raised More Than $100 Million
Fusion startups draw billions as CFS leads with $3.94 billion, while Helion, TAE and 13 rivals target breakeven and commercial power into the late 2030s.
Summary
FusionX lists 17 startups above $100 million. Faster chips, AI and high-temperature superconductors have advanced reactor designs, while a U.S. Department of Energy lab reached scientific breakeven in late 2022. Commercial breakeven remains distant.
Commonwealth Fusion Systems leads with $3.94 billion after July’s $1 billion round; Sparc targets operation by early 2027 and Q > 1 during 2027, followed by the 400-megawatt Arc near Richmond, with Google buying half its output. Helion has $3.2 billion, a $15.5 billion valuation and a 2028 Microsoft power deal. TAE raised $1.65 billion before its December 2025 all-stock Trump Media merger, valuing the combination at $6 billion and providing TAE $200 million plus $100 million after an SEC filing. Pacific Fusion secured a milestone-based Series A exceeding $1 billion for 156 generators producing 2-terawatt, 100-nanosecond pulses. Proxima raised $682.9 million, reached a $2.7 billion July valuation and targets Alpha in the early 2030s, then Stellaris.
Shine has $1 billion; Inertia launched with $450 million and signed three NIF commercialization agreements. General Fusion raised over $442 million, cut 25% of staff in spring 2025, secured $73.1 million that year, then gained $127 million from its July 13, 2026 Nasdaq listing. Zap has $325 million and added fission under CEO Zabrina Johal. Tokamak Energy has $284 million; Focused Energy, $277 million plus $200 million in grants; Marvel, $208 million; Type One, $174.5 million while raising $250 million for a 350-megawatt TVA-site plant; First Light, $140 million; Kyoto Fusioneering, $121 million; Thea, $120 million; and Xcimer, $101 million for a planned 10-megajoule laser.
Positives
- Commonwealth Fusion Systems plans 400-megawatt Arc near Richmond, and Google has committed to buy half its electricity.
- Helion’s agreement with Microsoft targets electricity production in 2028, the sector’s most aggressive commercial timetable.
- Inertia Enterprises raised $450 million and signed three April agreements to commercialize National Ignition Facility technology.
- Tokamak Energy’s ST40 produced 100-million-degree Celsius plasma in 2022, while Demo 4 will test magnets under power plant-relevant conditions.
- Focused Energy raised $277 million privately and received $200 million in grants, with RWE providing access to a decommissioned fission plant.
- Marvel Fusion expects its Colorado State University demonstration facility to become operational by 2027.
Risks & concerns
- Commercial breakeven remains far beyond the late 2022 scientific breakeven result, because an entire fusion facility still consumes more energy than it produces.
- General Fusion’s spring 2025 cash shortage triggered a 25% workforce reduction while it was building LM26 for a hoped-for 2026 breakeven result.
- Pacific Fusion’s investors will release its more than $1 billion commitment only in tranches tied to specified milestones.
- First Light Fusion abandoned its two-stage projectile plan and now offers core technologies to other inertial-confinement developers.
- Zap Energy added fission and hybrid plants to generate revenue earlier than fusion alone, signaling pressure on fusion commercialization timelines.
- Type One Energy is still raising a $250 million Series B for a plant not expected online until the mid-2030s.