Overview
- The Series G round, announced Thursday, brought $465 million and lifted Helion’s valuation to $15.5 billion, taking total capital raised to more than $1.5 billion.
- Helion is building a 50 MW plant called Orion in Malaga, Washington, and says the funding will speed manufacturing and site work tied to a power purchase agreement with Microsoft that targets 2028 delivery.
- The company’s Polaris prototype has reportedly run with deuterium‑tritium fuel and reached about 150 million °C, and Helion is adding smaller testbeds such as Tiny Merge to shorten development cycles.
- Investors in the round include Thrive Capital and returning backers, with high‑profile private investors such as Sam Altman disclosed as holding a major stake, while Helion’s leaders face calls for more peer‑reviewed data.
- If Helion scales its Field‑Reversed Configuration and direct inductive electricity capture as planned, the technology could change how always‑on clean power is delivered to data centers and energy‑intensive industry, but experts warn engineering, fuel and regulatory hurdles remain.