Separated electrolysis process paves methods for industrial scale green hydrogen production

A recent review of Nature Reviews Clean Technology presents for the first time a pathway expanding separation water electrolysis (DWE) technology to produce industrial-scale green hydrogen.

Hydrogen, the main chemical ingredient, is usually produced from fossil fuels and produces high CO2 emissions. Water electrolysis with renewable energy releases oxygen rather than CO2, providing a clean alternative. Green hydrogen production on an industrial scale is one of the holy grails of energy transitions as it unlocks the possibility of replacing the world’s dependence on fossil fuels.

Traditional electrolysis uses two electrodes separated from the membrane to divide water into hydrogen and oxygen. This approach is expensive, suffers from internal hydrogen leaks and is not compatible with intermittent solar and wind power.

DWE overcomes these problems by separating hydrogen and oxygen production in time or space, eliminating the need for membranes. Rather, it uses redox materials that can absorb and release ions from which oxygen or hydrogen is produced.

In this article, we review various DWE methods and present a scaling-up pathway that is viable for the first time. The authors include leading experts from around the world. Professor Avner Rothschild of the Technion School of Science and Engineering, Professor Mark D. Sims of the University of Glasgow, Professor Jens Orf Jensen of the Institute of Technology Denmark, Dr. Tom Smolinka of the Fraunhofer Institute for Fraunhofer Institute for Solar Energy, Dr. Gillin Luan, a postdoctoral researcher, and Fiona Todman, a doctoral student at the University of Glasgow.

Professor Mark Sims of the University of Glasgow and his collaborators used solution-phase redox mediators to pioneer the original embodiment of electrolysis isolated in 2013. He continues his work on separate electrolysis using a variety of liquid-based systems and is actively seeking to commercialize the technology through the Clyde hydrogen system.

In 2015, Professor Avner Rothschild pioneered new technologies with his colleagues at Technion, Professor Gideon Grader, Dr. Hen Dotan and Dr. Avigail Landman, using nickel-based redox electrodes. Their breakthrough led to the founding of H2PRO in 2019.

Professor Jens Oluf Jensen and Dr. Tom Smolinka are world-renowned experts in cutting-edge electrolytic technology. Their research in its application to proton exchange membranes (PEM), anion exchange membranes (AEM), electrode materials, and cell stacks for large capacity PEM and AEM electrolytic factors, provided valuable insight into the challenges and manipulation challenges of commercial electrolytic factors, and provided a sound base for comparison of the disruptive decupted electro-Zerzel concept. Rotem Arad and Gilad Yogev provide insights to translate these concepts into large-scale green hydrogen production techniques.

This review is DWE’s first detailed, viable scale-up strategy. Lab-scale DWE experiments produce less than 1 gram of hydrogen per day, while industrial systems need to produce about 1 ton of hydrogen per day.

In fact, approximately one million full-scale electrolyzers are required to meet current hydrogen demand. On the other hand, traditional industrial electrolyzers require a stable grid supply and can only be used in limited areas with very dynamic power fluctuations, such as those caused by solar and wind energy.

A unique advantage of DWE is its energy storage capabilities through redox materials, which acts like an electrolyzer with built-in batteries. This allows for buffering energy fluctuations from renewable energy sources, making it highly compatible with solar and wind systems, thus providing an important pathway to low-cost green renewable hydrogen production.

The potential impact of expanding green hydrogen production is significant. Currently, the hydrogen market is worth around $250 billion a year. Once available on an industrial scale, the green hydrogen market is expected to reach $550 billion within 10 years.

“We expect green hydrogen to account for 10% of the future energy market. Once green hydrogen is produced on a large scale and can be sold at reasonable prices, hydrogen will replace most of the energy used in industry, heavy transportation, and other sectors,” predicted Professor Rothschild.

“Traditional electrolyzers need to evolve to suit this market. As Darwin points out, it’s not the strongest species that survive through evolution, but rather they can adapt and adjust to the changing environment that it finds itself.

“The isolated electrolysis is about 12 years old. More conventional technologies, such as alkaline and proton exchange membrane cells, have been around decades (for centuries) for development.

“In our current orbit, we hope that, over the next decade, separate electrolysis systems will become a serious competitor for more traditional electrolytic agents, particularly for the conversion of renewable energy into green hydrogen.”

The new ideas presented in the review article are persuasive and shed light on the long-term prospects of expanding DWE technology for the benefit of all humanity.