Thea Energy Raises $100 Million To Scale Fusion Power Plants, Expand U.S. Energy Infrastructure

Thea Energy raised $100 million in Series B funding to expand magnet manufacturing and advance its integrated fusion system.
The capital will support Eos, a large-scale stellarator system designed to prove steady-state fusion for future power plants.
The company is targeting construction of its first Helios commercial fusion power plant before the end of the decade.

Thea Energy Targets Grid-Scale Fusion

Northern New Jersey is becoming a test bed for one of the highest-stakes energy bets in the U.S. power market.

Thea Energy has raised $100 million in Series B funding to accelerate the development of scalable fusion power plants. The round will expand the company’s magnet manufacturing capacity, support a second facility in Northern New Jersey, and advance construction of its integrated fusion system.

The company is developing stellarator-based fusion technology, an approach designed to provide stable, high-availability baseload power. For investors, utilities, hyperscalers, and policymakers, the financing comes at a critical moment. Power demand is rising fast due to artificial intelligence, electrification, industrial reshoring, and grid reliability pressures.

The round drew support from Thomas Tull’s US Innovative Technology Fund, General Innovation Capital Partners, Linse Capital, Calm Ventures, Climate Capital, Divergent Capital, Emerald Technology Ventures, Gaingels, Idemitsu Kosan, Overlay Capital, Timescale Ventures, and Whatif Ventures.

Existing investors also participated, including Alumni Ventures, Hitachi Ventures, Lowercarbon Capital, Mercator Partners, Orion Industrial Ventures, Prelude Ventures, and Starlight Ventures.

Capital Will Support Eos System And Magnet Manufacturing

The new funding will help Thea Energy expand its magnet manufacturing infrastructure. It will also support siting and construction of Eos, a large-scale integrated stellarator system.

Eos is designed to create power plant relevant, steady-state fusion using Thea Energy’s simplified architecture. The company says its approach could allow fusion systems to be built on shorter timelines and at lower cost than earlier designs.

Thea Energy plans to select a site for Eos later this year. It also plans to double its team as it moves from hardware validation toward larger-scale construction.

“We built Thea Energy to take fusion out of the lab and onto the grid. Our architecture is simpler to manufacture, faster to construct, and more tolerant of real-world conditions compared to all other approaches. Commercial fusion requires adaptable, high-uptime power plants; this Series B accelerates that reality,” said Brian Berzin, Co-Founder and Chief Executive Officer of Thea Energy. “With the U.S. Department of Energy (DOE)’s certification of our power plant preconceptual design milestone, proven magnet hardware, best-in-class team, and the capital now in place, we are on the path to delivering the first commercial stellarator power plants.”

The company said the round was oversubscribed. That demand reflects broader investor interest in firm, clean power technologies that can operate beyond the limits of intermittent generation.

Fusion Becomes A Strategic Energy Security Play

Fusion remains a long-horizon technology, but the market around it is changing. Governments and private investors are no longer viewing it only as a science project. They are increasingly treating it as strategic energy infrastructure.

That shift matters for the C-suite. Large power buyers, especially hyperscalers and industrial operators, need low-carbon electricity that can run continuously. Current grid constraints are becoming a material growth risk for data centers, advanced manufacturing, and heavy industry.

Thea Energy said it is already in discussions with more than a dozen power offtakers, hyperscalers, and utility partners. Those discussions point to a new phase for fusion developers, where commercial demand is forming before plants reach the grid.

“Thomas Tull has been clear about why he wanted USIT to lead this round: he believes the stellarator is the right architecture for commercial fusion, and Thea Energy is the company that makes it commercially viable,” said Gaetano Crupi, Managing Director at USIT. “The stellarator is an inherently stable fusion architecture that offers the most efficient path to long-term power generation, but prior 3D stellarator magnets historically made the system impractical to build. Thea Energy’s breakthroughs shift complexity from precision mechanical fabrication to software-defined controls. As energy security and rapidly increasing power demands take center stage amidst re-industrialization and the AI boom, the U.S. cannot cede leadership in fusion. Thomas believes this team and their software-based technology are a winning combination.”

DOE Milestone Strengthens Commercial Pathway

Thea Energy’s financing follows certification by the U.S. Department of Energy of its Helios power plant preconceptual design milestone. The company said it is the first awardee to receive that distinction.

Over the past 18 months, Thea Energy said it has de-risked core fusion technologies, including full-scale planar shaping magnets for the Eos system. It also built and operated what it described as the world’s first superconducting magnet array capable of producing the complex magnetic fields needed for commercial stellarator systems.

The company is now working toward the construction of its first Helios power plant before the end of the decade. If successful, Helios would move Thea Energy closer to a commercial fusion model built around scalable manufacturing rather than bespoke scientific infrastructure.

For investors and energy executives, the core question is no longer whether fusion can attract capital. It is whether developers can convert technical progress into bankable assets, credible offtake structures, and repeatable construction models.

Thea Energy’s latest round places that challenge squarely in the U.S. energy transition. As global competition intensifies, fusion is becoming a test of industrial policy, clean power strategy, and long-term energy security.