ABB has launched its thyristor-based water-cooled UNIREC H2 power rectifier for green hydrogen production, engineered to help operators reduce energy losses and operating costs as projects scale. Designed to convert AC electricity from the grid into the high-current DC power required by electrolysers, UNIREC H2 multi-pulse thyristor rectifier is designed to achieve power conversion efficiency of up to 99.6% at nominal current. Each unit can be configured to deliver up to 7.5 MW of DC power and 6 kA of output current, while modular architecture supports 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 and operating costs. Electricity accounts for an estimated 60 - 70% of the operating cost of electrolytic hydrogen production, making power-conversion efficiency an important lever in reducing the levelised cost of hydrogen (LCOH).
“Electricity consumption is fundamental to the economics of green hydrogen and as hydrogen projects expand, customers need power solutions that combine high efficiency and reliability with scalable architecture,” said Sarah-Xiaolan Huang, Global Product Manager for UNIREC H2 at ABB’s Energy Industries division. “UNIREC H2 is designed to help reduce energy losses while providing a reliable DC power platform for large-scale hydrogen production.”
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 surpassed 100 million t in 2025, while low-emissions hydrogen production grew by 20% to almost 1 million t. Installed electrolysis capacity also doubled during 2025 to more than 4 GW.
UNIREC H2 forms part of ABB’s wider approach to hydrogen plant electrification. Beyond power conversion, ABB can support customers from early-stage plant and power-supply evaluation through detailed design, helping assess electrolyser configuration, power architecture, energy storage, rectifier selection, power quality, and energy efficiency. Electrical studies, simulation, and plant controls can then help optimise how energy is used across the complete production system rather than considering the rectifier in isolation.
