Thea Energy Raises $100M Series B to Build Planar-Coil Stellarator Power Plants

Princeton-spinoff Thea Energy announced a $100 million Series B round on May 27, 2026, led by the US Innovative Technology Fund (USIT) and joined by a broad syndicate including Idemitsu Kosan, Lowercarbon Capital, Hitachi Ventures, and 12 other investors. The round brings total private capital raised to $130 million. Thea's approach — a planar-coil stellarator where dozens of mass-manufacturable flat magnets replace the complex 3D coils of classical stellarators — is designed to be far simpler to build at scale. The company received DOE certification of its Helios preconceptual design milestone, becoming the first Milestone-Based Fusion Development Program awardee to achieve that distinction, and has secured six DOE INFUSE awards. Funds will expand Thea's planar superconducting magnet manufacturing infrastructure with a second facility in Northern New Jersey and double its workforce. The company plans to site 'Eos' — a power-plant-relevant integrated demonstration device — in 2026, targeting construction of the first commercial 'Helios' plant before the end of the decade. CEO Brian Berzin stated: 'We built Thea Energy to take fusion out of the lab and onto the grid.'