Corrigendum to “Review of necessary thermophysical properties and their sensitivities with temperature and electrolyte mass fraction for alkaline water electrolysis multiphysics modelling” [Int J Hydrogen Energy 44 (2019) 4553–4569]

Alkaline water electrolysis is a key technology for large-scale hydrogen production powered by renewable energy. As conventional electrolyzers are designed for operation at fixed process conditions, the implementation of fluctuating and highly intermittent renewable energy is challenging. This contribution shows the recent state of system descriptions for alkaline water electrolysis and renewable energies, such as solar and wind power. Each component of a hydrogen energy system needs to be optimized to increase the operation time and system efficiency. Only in this way can hydrogen produced by electrolysis processes be competitive with the conventional path based on fossil energy sources. Conventional alkaline water electrolyzers show a limited part-load range due to an increased gas impurity at low power availability. As explosive mixtures of hydrogen and oxygen must be prevented, a safety shutdown is performed when reaching specific gas contamination. Furthermore, the cell voltage should be optimized to maintain a high efficiency. While photovoltaic panels can be directly coupled to alkaline water electrolyzers, wind turbines require suitable converters with additional losses. By combining alkaline water electrolysis with hydrogen storage tanks and fuel cells, power grid stabilization can be performed. As a consequence, the conventional spinning reserve can be reduced, which additionally lowers the carbon dioxide emissions.

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Pulse Electrodeposited CoFeNiP as Highly Active and Stable Electrocatalyst for Alkaline Water Electrolysis

Sustainable Energy & Fuels ◽

10.1039/d1se00350j ◽

2021 ◽

Author(s):

Yun Li ◽

Ruopeng Li ◽

Dan Wang ◽

Hao Xu ◽

Xiangyu Lu ◽

...

Keyword(s):

High Performance ◽

Water Electrolysis ◽

Cost Effective ◽

Hydrogen Energy ◽

Alkaline Water Electrolysis ◽

Alkaline Water ◽

Efficient Conversion ◽

Highly Active ◽

And Storage

Developing high-performance and cost-effective electrocatalysts for water electrolysis would make a great process for efficient conversion and storage of sustainable hydrogen energy. As a potential electrocatalyst, the improvement of water...

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Modelling and control of an alkaline water electrolysis process

International Journal of Computational Physics Series ◽

10.29167/a1i2p9-14 ◽

2018 ◽

Vol 1 (2) ◽

pp. 9-14

Author(s):

Marisol Cervantes-Bobadilla ◽

Ricardo Fabricio Escobar Jiménez ◽

José Francisco Gómez Aguilar ◽

Tomas Emmanuel Higareda Pliego ◽

Alberto Armando Alvares Gallegos

Keyword(s):

Process Model ◽

Water Electrolysis ◽

Alkaline Water Electrolysis ◽

Alkaline Water ◽

Electrolysis Process ◽

Linear Dynamic ◽

Energy Current ◽

Identification Technique ◽

Nonlinear Static ◽

And Control

In this research, an alkaline water electrolysis process is modelled. The electrochemical electrolysis is carried out in an electrolyzer composed of 12 series-connected steel cells with a solution 30% wt of potassium hydroxide. The electrolysis process model was developed using a nonlinear identification technique based on the Hammerstein structure. This structure consists of a nonlinear static block and a linear dynamic block. In this work, the nonlinear static function is modelled by a polynomial approximation equation, and the linear dynamic is modelled using the ARX structure. To control the current feed to the electrolyzer an unconstraint predictive controller was implemented, once the unconstrained MPC was simulated, some restrictions are proposed to design a constrained MPC (CMPC). The CMPC aim is to reduce the electrolyzer's energy consumption (power supply current). Simulation results showed the advantages of using the CMPC since the energy (current) overshoots are avoided.

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Boosting alkaline water electrolysis by asymmetric temperature modulation

Applied Physics Letters ◽

10.1063/5.0054273 ◽

2021 ◽

Vol 119 (1) ◽

pp. 013901

Author(s):

Qinpeng Zhu ◽

Peihua Yang ◽

Tao Zhang ◽

Zehua Yu ◽

Kang Liu ◽

...

Keyword(s):

Water Electrolysis ◽

Temperature Modulation ◽

Alkaline Water Electrolysis ◽

Alkaline Water

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Towards the Hydrogen Economy—A Review of the Parameters That Influence the Efficiency of Alkaline Water Electrolyzers

Energies ◽

10.3390/en14113193 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3193

Author(s):

Ana L. Santos ◽

Maria-João Cebola ◽

Diogo M. F. Santos

Keyword(s):

Energy Content ◽

Water Electrolysis ◽

High Energy ◽

Operating Conditions ◽

Energy Sources ◽

Alkaline Water Electrolysis ◽

Alkaline Water ◽

New Energy ◽

Recent Developments ◽

Cell Components

Environmental issues make the quest for better and cleaner energy sources a priority. Worldwide, researchers and companies are continuously working on this matter, taking one of two approaches: either finding new energy sources or improving the efficiency of existing ones. Hydrogen is a well-known energy carrier due to its high energy content, but a somewhat elusive one for being a gas with low molecular weight. This review examines the current electrolysis processes for obtaining hydrogen, with an emphasis on alkaline water electrolysis. This process is far from being new, but research shows that there is still plenty of room for improvement. The efficiency of an electrolyzer mainly relates to the overpotential and resistances in the cell. This work shows that the path to better electrolyzer efficiency is through the optimization of the cell components and operating conditions. Following a brief introduction to the thermodynamics and kinetics of water electrolysis, the most recent developments on several parameters (e.g., electrocatalysts, electrolyte composition, separator, interelectrode distance) are highlighted.

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