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The article presents a review of the research on green hydrogen from the social sciences identifying its main lines of research its problems and the relevant challenges due to the benefits and impacts that this energy vector has on energy transitions and climate change. The review analyzes a corpus of 78 articles indexed in the Web of Science (WoS) and SCOPUS published between 1997 and 2022. The review identified three research areas related to green Read More

Tailpipe emissions from vehicles consist of CO2 and other greenhouse gases which con‐ tribute immensely to the rise in global temperatures. Green hydrogen produced from the gasification of biomass can reduce the amount of CO2 emissions to zero. This study aims to provide a modelling framework to optimize the production of hydrogen from biomass waste obtained from different cities for use in the road transport sector in Nigeria. A gasification model Read More

The development of a hydrogen-based economy is the perfect nexus between the need of discontinuing the use of fossil fuels (trying to mitigate climate change) the development of a system based on renewable energy (with the use of hydrogen allowing us to buffer the discontinuities produced in this generation) and the achievement of a local-based robust energy supply system. However extending the use of hydrogen as an energy vector mus Read More

Activated carbons with different surface chemistry and porous textures were used to study the mechanism of electrochemical hydrogen and oxygen evolution in supercapacitor devices. Cellulose precursor materials were activated with different potassium hydroxide (KOH) ratios and the electrochemical behaviour was studied in 6 M KOH electrolyte. In situ Raman spectra were collected to obtain the structural changes of the activated carbons unde Read More

Hydrogen has the potential to be used by many countries as part of decarbonising the future energy system. Hydrogen can be used as a fuel ‘vector’ to store and transport energy produced in low-carbon ways. This could be particularly important in applications such as heating and transport where other solutions for low and zero carbon emission are difficult. To enable the safe uptake of hydrogen technologies it is important to develop the international scien Read More

Membrane reactors for hydrogen production can increase both the hydrogen production efficiency at small scale and the electric efficiency in micro-cogeneration systems when coupled with Polymeric Electrolyte Membrane fuel cells. This paper discusses the achievements of three European projects (FERRET FluidCELL BIONICO) which investigate the application of the membrane reactor concept to hydrogen production and micro-cogeneration Read More

Worldwide the road transport sector typically arises as one of the main sources of air pollutants due to its high energy intensity and the use of fossil fuels. Thus governments and social agents work on the development and prospective planning of decarbonisation strategies oriented towards sustainable transport. In this regard the increase in the use of alternative fuels is the recurrent approach to energy planning e.g. through the promotion of ele Read More

CeO2- ZrO2- and La2O3-supported Rh-Pt catalysts were tested to assess their ability to catalyze the steam reforming of ethanol (SRE) for H2 production. SRE activity tests were performed using EtOH:H2O:N2 (molar ratio 1:3:51) at a gaseous space velocity of 70600 h−1 between 400 and 700 °C at atmospheric pressure. The SRE stability of the catalysts was tested at 700 °C for 27 h time on stream under the same conditions. RhPt/CeO2 which showed the Read More

This paper proposes the use of the Point Method (PM) to analyse Environmentally Assisted Cracking (EAC) processes in steels containing U-shaped notches. The PM a methodology included within the Theory of Critical Distances (TCD) has been extensively validated by many authors for the analysis of fracture and fatigue phenomena of different types of materials containing notches. However it has never been applied to other critical or subcritical cracking p Read More

A nuclear reactor pressure vessel (NRPV) wall is formed by two layer of different materials: an inner layer of stainless steel (cladding material) and an outer layer of low carbon steel (base material) which is highly susceptible to corrosion related phenomena. A reduction of the mechanical properties of both materials forming the wall would appear due to the action of the harsh environment causing hydrogen embrittlement (HE) related phenomena. As Read More

Expectations for energy storage are high but large-scale underground hydrogen storage in porous media (UHSP) remains largely untested. This article identifies and discusses the scientific challenges of hydrogen storage in porous media for safe and efficient large-scale energy storage to enable a global hydrogen economy. To facilitate hydrogen supply on the scales required for a zero-carbon future it must be stored in porous geological formations Read More

Currently the technology associated with charging stations for electric vehicles (EV) needs to be studied and improved to further encourage its implementation. This paper presents a new energy management system (EMS) based on a Biogeography-Based Optimization (BBO) algorithm for a hybrid EV charging station with a configuration that integrates Z-source converters (ZSC) into medium voltage direct current (MVDC) grids. The EMS uses th Read More

In this study the optimal sizing of a hybrid battery/hydrogen Energy Storage System “ESS” is assessed via a model-based parametric analysis in the context of a real hybrid renewable microgrid located in Huelva Spain supplying a real-time monitored residential load (3.5 kW; 5.6 MWh/year) in island mode. Four storage configurations (battery-only H2-only hybrid battery priority and hybrid H2 priority) are assessed under different Energy Management Strat Read More

To achieve a vehicle-efficient energy management system an architecture composed of a PEM fuel cell as the main energy source and a hybrid storage system based on battery banks and supercapacitors is proposed. This paper introduces a methodology for the optimal component sizing aiming at minimizing the total cost achieving a cheaper system that can achieve the requirements of the speed profiles. The chosen vehicle is an urban transport bus w Read More

Grand Canonical Monte Carlo GCMC simulations are used to study the gravimetric and volumetric hydrogen storage capacities of different carbon nanopores shapes: Slit-shaped nanotubes and torusenes at room temperature 298.15 K and at pressures between 0.1 and 35 MPa and for pore diameter or width between 4 and 15 A. The influence of the pore shape or curvature on the storage capacities as a function of pressure temperature and pore diam Read More

This paper investigates environmental impacts of high pressure alkaline water electrolysis systems. An advanced system with membranes on polymer basis is compared to a state-of-the-art system with asbestos membranes using a Life Cycle Assessment (LCA) approach. For the advanced system a new improved membrane technology has been investigated within the EU research project “ELYGRID”. Results indicate that most environmental impacts are cau Read More

The Life Cycle Assessment (LCA) methodology is often used to check the environmental suitability of hydrogen energy systems usually involving comparative studies. However these comparative studies are typically affected by inconsistent methodological choices between the case studies under comparison. In this regard protocols for the harmonisation of methodological choices in LCA of hydrogen are available. The step-by-step application of these protocol Read More

Palladium-based membranes for hydrogen separation have been studied by several research groups during the last 40 years. Much effort has been dedicated to improving the hydrogen flux of these membranes employing different alloys supports deposition/production techniques etc. High flux and cheap membranes yet stable at different operating conditions are required for their exploitation at industrial scale. The integration of membranes in mul Read More

Producing hydrogen by water electrolysis suffers from the kinetic barriers in the oxygen evolution reaction (OER) that limits the overall efficiency. With spin-dependent kinetics in OER to manipulate the spin ordering of ferromagnetic OER catalysts (e.g. by magnetization) can reduce the kinetic barrier. However most active OER catalysts are not ferromagnetic which makes the spin manipulation challenging. In this work we report a strategy with spin pinnin Read More

Whereas noise generated by road traffic is an important factor in urban pollution little attention has been paid to this issue in the field of hydrogen-fueled vehicles. The objective of this study is to analyze the influence of the type of fuel (gasoline or hydrogen) on the sound levels produced by a vehicle with an internal combustion engine. A Volkswagen Polo 1.4 vehicle adapted for its bi-fuel hydrogen-gasoline operation has been used. Tests were carried o Read More

The safest way to store hydrogen is in solid form physically entrapped in molecular form in highly porous materials or chemically bound in atomic form in hydrides. Among the different families of these compounds alkaline and alkaline earth metals alumino-hydrides (alanates) have been regarded as promising storing media and have been extensively studied since 1997 when Bogdanovic and Schwickardi reported that Ti-doped sodium alanate could be re Read More

The most profitable offshore energy resources are usually found away from the coast. Nevertheless the accessibility and grid integration in those areas are more complicated. To avoid this problematic large scale hydrogen production is being promoted for far offshore applications. The main objective of this paper is to analyze the ability of wave energy converters to maximize hydrogen production in hybrid wind and wave far offshore farms. To that end wind Read More

A sustainability assessment regarding the manufacturing process and the use of a new proton exchange membrane fuel cell (PEMFC) specially designed for portable hydrogen applications is presented. The initial fuel cell prototype has been configured by taking into account exclusively technical issues. However a life cycle analysis considering environmental and socioeconomic impacts is crucial to improve the model to develop a more sustainable product. F Read More

In order to favor a transition to a renewable energy economy it is necessary to study the possible permeation of renewable energy sources not only in the electric grid or industrial scale but also in the small householding scale. One of the most interesting technologies available for this purpose is solar energy since it is a mature technology that can be easily installed in every rooftop. Thus a techno-economic assessment was carried out to evaluate the i Read More

The paper presents an overview of the main achievements of the internal project InsHyde of the HySafe NoE. The scope of InsHyde was to investigate realistic small-medium indoor hydrogen leaks and provide recommendations for the safe use/storage of indoor hydrogen systems. Additionally InsHyde served to integrate proposals from HySafe work packages and existing external research projects towards a common effort. Following a state of t Read More