Stiesdal Hydrogen is working to accelerate the development of affordable green hydrogen.

The HydroGen Electrolyzer is a 3.1 MW unit for pressurized hydrogen production at low cost.

The HydroGen technology represents a fully industrialized system approach in which not only the stack itself, but also the installation process and Balance of Stack are designed for efficient, standardized deployment.

Two 3.1 MW HydroGen Electrolyzers at a customer site. Each system unit comprising of standardized and modularized components.
The pressurized tanks enable the electrode stacks to supply hydrogen at pressures of up to 35 bar without the need for compression.
The electrode stack system is of a novel design that allows for easy handling of the full stack in and out of the electrolyzer pressure vessel.
Delivery of the main system component, the pressurized tank containing the electrode stack, to a customer site.
The power and process modules are standardized components supplied by established industrial partners.

Designed for the next generation green hydrogen plant

The HydroGen technology is based on a rethinking of traditional hydrogen electrolyzers, transitioning from a chemical industry design approach to a system designed to integrate seamlessly with renewable energy sources.

This approach supports the expansion of next-generation green hydrogen plants and aligns with global efforts to decarbonize hard-to-abate sectors.

Unique features of the HydroGen Electrolyzer

  • A modular system architecture designed for mass production by established industrial partners and suppliers with a global footprint.
  • A self-contained unit suitable for easy transportation and outdoor installation, requiring no buildings.
  • Minimal Balance-of-Plant requirements enabling rapid installation.
  • A unique pressure vessel concept delivering hydrogen at elevated pressure without compression losses.
  • Dynamic operating capability, allowing the system to follow volatile electricity prices and operate flexibly with wind and solar power.
Three 3.1 MW units are operating at the Glansager site in Denmark. Through its industrialized design, ease of installation, and operational flexibility, the HydroGen Electrolyzer demonstrates a practical pathway toward large-scale, cost-effective green hydrogen production.

HydroGen’s dynamic range performance

Future green hydrogen production will increasingly rely on wind and solar energy. This requires hydrogen systems that can operate as flexible electricity consumers.

HydroGen’s active front-end is designed for this future, enabling hydrogen production to participate on the demand side of electricity markets while following variable renewable power generation.

Technical specifications of pressurized alkaline electrolysis

Nominal AC power input 3.1 MW
Hydrogen production rate (net pure H₂) Up to 639 Nm³ H₂ per hour
Hydrogen delivery pressure Ambient to 35 bar
Hydrogen purity Minimum 99.5%
Guaranteed system efficiency (AC) 71% at 25% load

75% at 40-80% load

 73% at 100% load
Start-up time Below 5 minutes
Operating range 25-100% load
Ramp-up rate 1% load per second
Ramp-down rate 100% load per second

Full system industrialization

The HydroGen Electrolyzer is designed for rapid installation.

The entire electrolyzer system is delivered on two trucks. Once on site, installation consists primarily of mounting the modules on pre-installed point foundations followed by mechanical and electrical completion at clearly defined interfaces.

The Balance of Plant is minimized, with no requirement for buildings or large support systems.

Why alkaline

The HydroGen Electrolyzer is based on conventional alkaline electrolysis.

Alkaline technology uses electrodes made from abundant materials and does not require the noble metal catalysts used in other electrolysis technologies. It operates at relatively low temperature, supporting long system lifetime.

The simplicity of alkaline electrolysis is highly compatible with large-scale industrial production and use of standard industrial technologies.

Esben Baltzer Nielsen, Head of Sales and Business Development

Get in touch

Interested in exploring how our hydrogen solutions can benefit your project?

Reach out directly to Esben Baltzer Nielsen, Head of Sales and Business Development.

Email: ebn@stiesdal.com

Connect with Esben on LinkedIn.