Heron Power just raised $140 million to manufacture gigawatts of solid state transformers for data centers and the grid. It follows a $38 million Series A in May.
Founded by former Tesla executive Drew Baglino, Heron is targeting a century old bottleneck: the iron core transformer. Cheap and reliable, yes. Also bulky, heat heavy, and poorly suited for AI scale infrastructure.
Solid state transformers replace passive metal with semiconductors. The result is smaller footprint, intelligent power management, and fewer intermediary components. Heron’s product, Heron Link, converts medium voltage to 800V for modern AI racks, including reference designs from Nvidia. Each unit handles 5 megawatts and is modular. If a module fails, it swaps in minutes instead of hours or days.
Each system also includes fast discharge lithium ion buffers that provide about 30 seconds of bridge power. That can eliminate traditional UPS systems and remove up to 70 percent of related gear in some configurations.
The Series B was led by Andreessen Horowitz’s American Dynamism Fund and Breakthrough Energy Ventures, with participation from Capricorn, Energy Impact Partners, Gigascale Capital, and Valor Atreides AI Fund.
Heron plans to build a factory capable of producing 40 gigawatts annually, roughly 10 to 15 percent of non China global supply. Pilot production is targeted for early 2027, followed by a two year ramp.
