Kalla Test Center

We have taken a significant step towards possible future commercial P2X plants. Our Kalla hydrogen test center in Loviisa Finland will use two different electrolyser technologies, allowing for wider technological comparison and optimisation. The project is worth €17 million and covers both the construction and the operational phases.

The main objective of the project is to pilot hydrogen production and provide a reference for future P2X projects. We will test two different technologies, Alkali and PEM electrolysers, at the pilot plant to compare their characteristics and performance. We also want to understand the safety, performance and maintenance of hydrogen production and test the potential for flexibility.

Construction work has already started and production is expected to start in late 2025, with production continuing for about two years, between 2025 and 2028. This schedule will allow us to gather valuable data and experience to support potential future P2X projects.
 

 

Project Stakeholders

• Fortum Power and Heat Oy owns the Kalla pilot plant and will operate it with its own resources. During construction, Fortum is responsible for project management and also acts as the owner’s engineering.
• Fortum Waste Solutions Oy - part of NG Group is responsible for groundworks.
• Euromekanik AB acts as the plant integrator and is responsible for equipment installations.
• Stargate OÜ supplies the alkaline electrolyser.
• Hystar A/S supplies the PEM electrolyser.
• Valmet Automation Inc. supplies automation

Water Electrolysis

Water (H₂O) can be split into hydrogen (H₂) and oxygen (O₂) in an electrolyser cell using an electric current. The electrolyser cells consist of two electrically conductive electrodes, an anode and a cathode, and an electrolyte between them. The electrolyte can be either liquid or solid. When direct current is applied to the electrolyser cell, the resulting potential difference causes a reaction where oxygen forms at the positively charged anode and hydrogen forms at the negatively charged cathode.

In an alkaline water electrolyser (AWE), the electrodes are immersed in an alkaline solution, typically about 30% potassium hydroxide (KOH), which acts as the electrolyte. There is also a gas-impermeable membrane between the electrodes to keep the produced hydrogen and oxygen separate.
 

In a PEM electrolyser (PEM = proton exchange membrane), a polymer membrane that conducts electricity but is impermeable to gases is installed between the electrodes and acts as the electrolyte. In this case, no separate liquid electrolyte is needed.
Commercial electrolysers have multiple cells connected together to increase hydrogen production. At full capacity, the Kalla plant uses about 1.75 MW electricity and produces about 32.5 kilograms of hydrogen per hour.
 

Both AWE and PEM electrolyser plants have numerous auxiliary equipment around the electrolyser itself, such as water purification, purification of the produced hydrogen gas, and removal of heat generated in the process. This equipment is fundamentally similar regardless of which electrolyser technology is chosen.