Volume 9, Issue 1, February 2025

This special issue highlights the generation, application, and safe use of low-carbon hydrogen produced from renewable energy sources.

The potential industrial applications of hydrogen produced from renewable sources are reviewed, focusing on anticipated advancements and adoption over the next 15 years.

An innovative online monitoring scheme for real-time measurement of the anode exhaust mixture concentration from a proton exchange membrane fuel cell stack utilizes an ultrasonic flowmeter. This scheme offers high measurement accuracy, short sampling intervals, simple configuration, and low cost.

An electrochemical model is implemented in Aspen Plus to analyze the power generation performance of a syngas-fed solid oxide fuel cell stack under various temperature and gas conditions. The design parameters and power generation performance for a 20-kW power generation module are determined.

A commercial-size 10-cell proton exchange membrane fuel cell stack is characterized by multipoint voltage and impedance sweep experiments. The output characteristics of the stack at various loads under are analyzed using fixed-frequency multipoint impedance. A sensitivity analysis is conducted to assess the effects of key parameters.

The kinetics of hydrogen production via ethanol steam reforming using a nickel-based catalyst are investigated experimentally. This study provides key insights into the reaction mechanisms and highlights the effectiveness of the nickel-based catalyst.

Hydrogen’s potential as a pivotal clean energy carrier is reviewed, focusing on its role in replacing fossil fuels across various industries. This study also examines recent advancements in hydrogen production technologies. Special attention is given to hydrogen produced from renewable sources

Lanthanum titanium oxycarbide and neodymium titanium oxycarbide are synthesized through solid-state reaction to replace titanium oxycarbide due to its rapid charge carrier recombination and limited responsiveness to visible light in photocatalysis.

Critical aspects of offshore green hydrogen production are discussed. Key findings show that the levelized cost of hydrogen is significantly influenced by the cost of electricity from offshore wind farms, capital cost of electrolyzers, and logistics of platforms, pipelines, and storage.

Advancements in solar-powered hydrogen technologies are reviewed, including production methods, storage systems, and their integration with renewable energy solutions. Thermochemical, photochemical, and biological hydrogen production methods are considered.

A two-dimensional theoretical cavitation flow model of the labyrinth seal between the piston and cylinder in a liquid hydrogen piston pump is established, based on the thermodynamically modified Zwart cavitation model. The influence of cavitation on the pressure distribution along the clearance seal is analyzed.

The flow, heat transfer, and reaction performance of microchannel multistream heat exchangers coupled with ortho–para hydrogen conversion is modeled using a one-dimensional model of the heat exchanger, while considering the flow arrangement inside the heat exchanger.

Mg-Nb oxides are added to ball-milled MgH₂ to improve the material’s adsorption and desorption of hydrogen. The Johnson–Mehl–Avrami equation is used to construct H₂ desorption curves and calculate reaction rate constants at different temperatures.

The current development trajectories of renewable energy and hydrogen energy in China are summarized, including advantages, disadvantages, and economic comparisons of various underground hydrogen storage methods, with emphasis on the merits of salt cavern hydrogen storage.

The submerged high-pressure liquid hydrogen pump is a core piece of equipment for liquid hydrogen transportation. Failure probabilities, and the consequences of those failures, for each part of the liquid hydrogen pump are identified with reference to typical industry failure probabilities.

The effects of hydrogen pipeline leaks and ambient wind on the volume of the flammable hydrogen cloud are studied. Computational fluid dynamics is used to investigate the effects of wind and the position, diameter, shape, and direction of leakage holes on the diffusion characteristics of hydrogen leaks.

Hydrogen-air explosions inside a confined space are simulated numerically, considering the number and placement of vents intended to reduce the damage from explosion. A geometric model considering internal and external explosion is established.

Industrial computed tomography scanning was carried out on a type III hydrogen storage composite overwrapped pressure vessel with an aluminum alloy liner and a carbon fiber wound layer to identify microscopic defects.

The flame resistance characteristics of a corrugated flame arrester and the mechanisms affecting hydrogen explosions are visually investigated by varying the structural parameters of the corrugated flame-retardant system and the concentration of hydrogen.

Hydrogen gas leakage detection sensors are reviewed, including types such as ultrasonic, electrochemical, metal oxide (MOX), catalytic, and fiber Bragg grating sensors.

This study provides insights into the dynamics of overpressure in hydrogen explosions in open spaces by experimentally analyzing flame propagation and overpressure distribution. It also evaluates the accuracy of three theoretical models in predicting peak overpressure.