Sunfire and KK Group Partner on 100 MW Green Hydrogen Plant

Sunfire selected KK Group for their ability to deliver customised Power Supply Units that convert electricity from the grid into stable, efficient power for the electrolyzers, meeting specific grid and plant requirements.

Building on a successful pilot project
The partnership builds on a pilot plant located at the same site, marking the first step towards large-scale electrolysis in Germany.

In 2023, KK Group supplied two Power Supply Units for Sunfire’s 10 MW pilot electrolyzer, each featuring a 5 MW rectifier, transformer, control system, and integrated cooling, which produces up to 270 kg of green hydrogen per hour.

“KK Group clearly understood our technical requirements and showed flexibility in adapting their Power Supply Units to meet electrolyzer specifications, plant-level requirements, and grid requirements—giving us confidence as we scale up to the 100 MW project,” explains Robert Brankatschk, Senior Manager, Project Management, Electrolysis at Sunfire.

Customised power supply for hydrogen
Each PSU is purpose-built for hydrogen applications, featuring a customised design that includes rectifiers, transformers, and integrated cooling. To enhance reliability and simplify maintenance, traditional AC busbar systems were replaced with insulated cabling. These and other design adaptations ensured alignment with Sunfire’s specific engineering specifications.

With a longstanding track record in power conversion for the wind industry, KK Group applies its expertise to hydrogen, where many technical and operational requirements overlap. This allows KK to customise PSUs efficiently while leveraging its established supply chains and engineering practices.

“We customise at the product, organisational, and process levels—adapting components, mirroring team structures, and applying our APQ4Wind quality methodology from the wind industry. Leveraging proven products and supply chains helps customers avoid reinventing the wheel, significantly reducing costs and timelines,” says Michael Ariel Nielsen, Head of Power-to-X at KK Group.

And he continues:

“By utilising our APQ4Wind methodology, we ensure consistent processes and maintain high product quality. Implementing this approach in collaboration with Sunfire enables us to help establish much-needed standards in the hydrogen industry, which is still in its early stages.”

Anticipated impact and future collaboration
Sunfire expects the customised PSU solution to support the reliable operation of its electrolyzer system, reduce integration costs, and improve project financing prospects through verified efficiency and performance data. The partnership also sets the stage for potential future projects, with KK Group’s PSU product offering the potential for further scale.

Production activities have begun, including testing and quality verification.

“We value KK Group’s technical expertise and open collaboration. Their adaptable approach, focus on performance, and reliable PSU solutions make them a key partner for our largest project to date,” says Robert Brankatschk, Senior Manager, Project Management, Electrolysis at Sunfire.



About Sunfire
Sunfire is a global leader in the production of industrial electrolyzers based on pressurized alkaline and solid oxide (SOEC) technologies. With its electrolysis solutions, Sunfire is addressing a key challenge of today’s energy system: Providing renewable hydrogen and syngas as climate-neutral substitutes for fossil energy. Sunfire’s innovative and proven electrolysis technology enables the transformation of carbon-intensive industries that are currently dependent on fossil-based oil, gas, or coal. The company employs more than 650 people located in Germany and Switzerland.