First Hydrogen Production for Climate-Friendly Regional Transportation in Carinthia

The “greenelectrolyzer gEL400” PEM electrolysis plant, built in Arnoldstein for Kelag with an electrical output of two megawatts, is designed for continuous operation in a mobility-related application scenario and produces green hydrogen exclusively from renewable, regionally available energy. During normal operation, approximately 140 metric tons of hydrogen are produced annually, enabling the daily operation of up to 36 hydrogen buses in regional transit.

FEST developed a compact, industrial-grade electrolysis solution. Particular emphasis was placed on stable continuous operation, short ramp-up times, and integration into the site’s existing infrastructure.

The facility opened in April 2026, and regular production operations began in May 2026. The project is one of the fastest-implemented hydrogen mobility solutions in public transportation in Austria and serves as a real-world reference case for the successful introduction of hydrogen technology into routine operations.

With the project in Arnoldstein, FEST underscores its expertise in implementing industrial electrolysis solutions for mobility applications. The facility makes a measurable contribution to reducing CO₂ emissions in local public transit and supports the long-term climate goals of the state of Carinthia. At the same time, the project demonstrates how hydrogen production, existing infrastructure, and renewable energy sources can be efficiently combined into a scalable, comprehensive solution.