ABB has launched its thyristor-based water-cooled UNIREC H2 multi pulse power rectifier for green hydrogen production, engineered to help operators reduce energy losses and operating costs as projects scale up. Designed to convert the grid AC supply into the high-current DC power required by electrolysers, the rectifier is capable of achieving a power conversion efficiency of up to 99.6 % at nominal current, a figure based on performance calculations of the converter at rated operating conditions in accordance with IEC 60146-1-1.
Each unit can be configured to deliver up to 7.5 MW of DC power at an output current of 6 kA, while its modular architecture can support hydrogen plants ranging from megawatt-scale installations to projects exceeding 1 GW.
For large-scale hydrogen plants, even small improvements in power conversion efficiency can translate into meaningful reductions in electricity consumption. Electricity accounts for an estimated 60-70 % of the operating cost of electrolytic hydrogen production, making power-conversion efficiency an important factor in reducing the levelised cost of hydrogen.
The launch comes as the hydrogen industry seeks project economics improvements to support larger-scale deployments. According to the International Energy Agency, global hydrogen demand exceeded 100 million tonnes in 2025, while low-emissions hydrogen production grew by 20 % to almost 1 million tonnes. Installed electrolysis capacity also doubled during 2025 to more than 4 GW.
Danilo Moresco, Global Business Line manager, Power Reliability, at ABB’s Energy Industries division commented: “UNIREC H2 is designed to reduce energy losses at the point of power conversion, but the opportunity goes beyond a single piece of equipment. By looking at power architecture, controls and energy optimisation across the plant, we can help operators make more effective use of every megawatt available.”
UNIREC H2 is designed for continuous high-current industrial operation, supporting gigawatt-scale production to deliver bulk baseload power for applications where LCOH and bankability are key. Its simplified architecture is said to eliminate common wear components such as electrolytic capacitors, while standardised modular power stacks support future expansion and long-term operation.
