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On-site hydrogen generation for generator cooling

For power plants with hydrogen-cooled generators, hydrogen production must work alongside existing storage, controls and operating procedures. Hydrogenera combines on-site hydrogen generation with plant-specific automation to meet these requirements.
A recent 60 kW Z Series installation at a thermal power plant demonstrates this approach. The project integrates hydrogen production with customised controls for the plant’s existing hydrogen storage and filling process.

Why hydrogen supply matters

Large electrical generators produce considerable heat during operation. In hydrogen-cooled generators, hydrogen circulates as a cooling medium. Its thermal properties support effective heat transfer, while its low density reduces aerodynamic resistance around rotating components.
The plant needs a supply of make-up hydrogen to replenish hydrogen lost from the cooling circuit during operation. Gas purity, pressure, and moisture content must meet the generator’s requirements.
On-site electrolysis provides a dedicated hydrogen source at the point of use. Combined with appropriately sized storage and supply arrangements, it can reduce dependence on external deliveries and support the plant’s operating needs.

Engineering around the existing plant

Integrating hydrogen production into an operating power plant starts with understanding its infrastructure and procedures.
Hydrogen demand determines the required production capacity. Delivery pressure, purity, and moisture specifications define the gas treatment requirements. Existing storage and control systems influence how the installation starts, stops, and supplies hydrogen.
Hydrogenera develops its process automation in-house. This allows control sequences and operating logic to be configured around each site’s requirements, alongside the hydrogen production equipment.
Depending on the project, the scope can include storage pressure management, automatic filling sequences, alarms, interlocks, remote monitoring and communication with the plant’s control system.

Restoring on-site hydrogen production

The thermal power plant had previously produced hydrogen on site for generator cooling. When its existing equipment stopped operating, it switched to an external hydrogen supply.
Hydrogenera supplied a 60 kW Z Series alkaline electrolysis system to restore on-site production. The system produces approximately 1 kg of hydrogen per hour at 99.999% purity (5N), with customised controls for hydrogen production and storage filling. The project covered engineering, delivery, installation, automation development, integration, commissioning and on-site testing.
A central part of the project was integrating the new system with the plant’s existing hydrogen storage infrastructure.
Hydrogenera developed the control logic around the storage-filling process and the operators’ working procedures. The automation coordinates hydrogen production with storage conditions and the control sequences needed for filling. It was designed to reduce routine manual intervention.
Developing the automation internally allowed Hydrogenera to adapt the operating logic during engineering and commissioning. Feedback from the plant’s technical team informed adjustments to the controls and additional functionality.

Client feedback

The client’s recommendation letter describes the installation’s performance during commissioning:
“During the commissioning and on-site testing phase, the system met all agreed technical specifications and demonstrated reliable operation, high performance and consistent hydrogen quality. The project was completed successfully and in accordance with the agreed implementation schedule.”
From the power plant operator’s recommendation letter.

Applying the approach to other power plants

For power plants considering on-site hydrogen production, the first step is to assess hydrogen demand, gas quality requirements and existing storage capacity. Available utilities, backup supply arrangements and control interfaces also shape the system design.
Hydrogenera uses this assessment to define the production equipment and automation the site needs. The installation described here demonstrates how that approach can restore on-site hydrogen production while integrating with existing storage and operating procedures.
Power plant operators evaluating on-site hydrogen supply can contact Hydrogenera to discuss production capacity, gas quality, storage integration and automation requirements.
2026-09-23 11:20 Project