Spiral Hydrogen, an Estonian-Dutch deeptech startup based in Rotterdam, has raised €2.7 million in pre-seed funding to develop its bubble-free electrolysis technology for green hydrogen production. The round was backed by byFounders, Norrsken Evolve, and Superangel, alongside €0.7 million in grants.

The new funding is intended to help the company move from laboratory development to pilot deployment. Spiral Hydrogen said it will use the capital to advance its rotating electrolyser technology and build its first pilot system at the Port of Rotterdam in partnership with SwitcH2.

The startup is developing a rotating, bubble-free electrolyser designed to improve efficiency in hydrogen production by reducing energy losses typically caused by gas bubble formation. The pilot project will test the technology in industrial conditions as the company works toward commercial scale.