The rapid scale up of electrolyzer plants into the hundreds of megawatts is fundamentally changing how hydrogen production interacts with energy systems. Large scale electrolyzers are no longer treated merely as passive industrial loads; instead, they are increasingly required to actively support grid stability under tightening grid code regulations across Europe and beyond. New requirements encompass reactive power provision, and advanced dynamic functions such as Fault Ride Through (FRT), which is expected to become mandatory for demand side assets in Europe by the late 2020s.

Meeting these requirements is particularly challenging for electrochemical processes, which inherently respond more slowly than power electronics and must do so without compromising safety, availability, or asset lifetime. This contribution discusses how coordinated plant wide design – spanning power supply, electrolyzer system, and downstream components – enables compliance with evolving grid codes. It highlights the role of an improved project execution, which takes into account the increased demands for the grid code approval process, which is becoming similar now to power generation units. The presentation will showcase the Kassø electrolyzer project in Denmark which serves as an example of how grid compliance can be shown for electrolysis, and how FRT capabilities can be integrated into large scale hydrogen production, supporting the reliable incorporation of clean hydrogen into renewable energy systems.