Thea Energy Secures $100M for 'Simpler' Stellarator Fusion Power

KEARNY, N.J. – May 27, 2026 – Thea Energy, a firm aiming to solve one of clean energy's most complex puzzles, has secured $100 million in an oversubscribed Series B funding round to accelerate its development of commercial fusion power plants. The investment, led by Thomas Tull’s US Innovative Technology Fund (USIT), signals growing confidence in the company's novel approach to a fusion architecture known as the stellarator.

The capital infusion will be used to expand magnet manufacturing, build a large-scale integrated fusion system, and move closer to the ambitious goal of putting fusion energy on the grid before the end of the decade. This funding arrives at a critical moment, as the global demand for carbon-free, baseload power surges, driven by re-industrialization and the voracious energy needs of the artificial intelligence boom.

"We built Thea Energy to take fusion out of the lab and onto the grid," said Brian Berzin, Co-Founder and Chief Executive Officer of Thea Energy. "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."

Reinventing a Classic Fusion Design

At the heart of Thea Energy's strategy is its reinvention of the stellarator, a device that uses powerful magnetic fields to contain the superheated plasma required for fusion reactions. Historically, stellarators have been seen as a more stable alternative to their more common cousin, the tokamak, as they can operate continuously and are not prone to damaging plasma disruptions. However, their Achilles' heel has always been complexity; traditional stellarators require incredibly intricate, twisted 3D magnetic coils that are a nightmare to manufacture and maintain.

Thea Energy, which spun out of Princeton University and the Princeton Plasma Physics Laboratory (PPPL) in 2022, tackles this challenge head-on. The company’s innovation, developed by co-founder and CTO Dr. David Gates, uses arrays of simple, flat, mass-manufacturable planar coils. This design, which recently earned a 2024 Edison Patent Award from PPPL, shifts the complexity from physical hardware to sophisticated software.

Instead of relying on fixed, twisted magnets, the company’s system uses software-defined controls to dynamically shape the magnetic fields. This allows for greater operational flexibility and a modular maintenance scheme, potentially slashing construction time and costs. The approach has been validated in a series of peer-reviewed papers and, crucially, by the U.S. Department of Energy (DOE).

"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," noted Gaetano Crupi, Managing Director at USIT, the lead investor. "Thea Energy’s breakthroughs shift complexity from precision mechanical fabrication to software-defined controls."

The Competitive Race to a Fusion-Powered Grid

The $100 million raise places Thea Energy on stronger footing in the increasingly competitive private fusion industry, a sector that has attracted nearly $10 billion in total funding. While the ultimate goal is shared, the paths to a commercial fusion plant are diverse.

Companies like Commonwealth Fusion Systems, an MIT spinout, are advancing the more traditional tokamak design using powerful new high-temperature superconducting magnets. Helion Energy is pursuing a unique magneto-inertial fusion concept, aiming to generate electricity directly from colliding plasma rings for clients like Microsoft. Meanwhile, TAE Technologies is focused on an alternative fuel cycle to minimize radioactivity.

Within this landscape, Thea Energy's bet on a simplified stellarator stands out. Its progress is underscored by its status as the first company in the DOE’s Milestone-Based Fusion Development Program to have its preconceptual power plant design certified. This program, modeled on NASA's successful COTS initiative that spurred the private space industry, provides non-dilutive funding and, more importantly, rigorous external validation from independent experts. This certification of the "Helios" power plant design confirms the scientific and engineering feasibility of the company's approach, a significant de-risking event for investors and future partners.

Powering the Future Amid Surging Demand

The significant investment from a syndicate including USIT, General Innovation Capital Partners, and Linse Capital is not just a bet on a single technology but a response to massive macroeconomic trends. The global push for decarbonization, coupled with a renewed focus on energy security, has created an urgent need for new sources of clean, reliable power.

Exacerbating this demand is the explosive growth of artificial intelligence. Data centers for training and running AI models require immense and constant supplies of electricity, putting unprecedented strain on existing power grids. Fusion energy, with its promise of zero-carbon, high-availability baseload power, is increasingly seen as a necessary long-term solution. Thea Energy is already in discussions with over a dozen potential customers, including power offtakers, hyperscale data center operators, and utilities, all looking to secure a future-proof energy source.

The new funding will directly support the next concrete steps on this path. The company plans to add a second magnet manufacturing facility in Northern New Jersey and is currently evaluating sites across five states for "Eos," its large-scale integrated stellarator system designed to demonstrate power-plant-relevant performance. A site selection is expected later this year, with the company also planning to double its team to execute this next phase. The ultimate goal is to begin construction of the first commercial power plant, dubbed "Helios," before the end of this decade.

This accelerated timeline is further enabled by a clearer regulatory environment. In 2023, the U.S. Nuclear Regulatory Commission (NRC) voted to regulate fusion energy systems under a framework designed for particle accelerators, separating them from the more stringent regulations governing nuclear fission. This decision, now being codified into law, provides the regulatory certainty that is critical for attracting long-term investment and planning large-scale infrastructure projects, positioning the U.S. as a leader in the global race to commercialize fusion energy.