ABB: UNIREC H2 High-Efficiency Rectifier to Help Reduce Green Hydrogen Power Costs
October 20, 2026
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 electrolyzers, UNIREC H2 multi-pulse thyristor rectifier is designed to achieve power conversion efficiency of up to 99.6 percent at nominal current1. 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 percent2 of the operating cost of electrolytic hydrogen production, making power-conversion efficiency an important lever in reducing the levelized 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 tonnes in 2025, while low-emissions hydrogen production grew by 20 percent to almost 1 million tonnes3. 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 electrolyzer configuration, power architecture, energy storage, rectifier selection, power quality and energy efficiency. Electrical studies, simulation and plant controls can then help optimize how energy is used across the complete production system rather than considering the rectifier in isolation.
“Making better use of electricity is central to helping green hydrogen production scale,” said Danilo Moresco, Global Business Line Manager, Power Reliability at ABB’s Energy Industries division. “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 optimization 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 eliminates common wear components such as electrolytic capacitors, while standardized modular power stacks support future expansion and long-term operation.
