Germany

Converting renewable electricity via water electrolysis into green hydrogen and hydrogen-based products will shape a global trade in power-to-x (PtX) products. The European Union's renewable hydrogen import target of 10 million tonnes by 2030 reflects the urgent need for PtX imports by sea to early high-demand countries like Germany. This study evaluates the cost efficiency and greenhouse gas (GHG) emissions of four hydrogen carrier ship import Read More

Proton exchange membrane electrolytic cells (PEMECs) have the potential to provide green Hydrogen as a sustainable energy source. PEMEC has already been applied at an industrially relevant scale. However it still faces challenges regarding reliability and durability especially in long-term operation. This review emphasizes the need for standardizing the cell configuration the testing protocols and the evaluation procedures to attain the optimum operation Read More

Underground hydrogen storage in salt caverns is a promising solution for short-term storage allowing multiple cycles per year. This study experimentally investigates the integrity of such caverns and their wellbores under operating conditions typical of German salt caverns. Specifically we measure the permeability of rock salt cement (API Class G and High Magnesium Resistant (HMR+)) rock salt-anhydrite composites cement-salt composites and Read More

Chapters:♦ Introduction by Rainer Quitzow and Yana Zabanova♦ The EU in the Global Hydrogen Race: Bringing Together Climate Action Energy Security and Industrial Policy by Yana Zabanova♦ Germany’s Hydrogen Strategy: Securing Industrial Leadership in a Carbon–Neutral Economy by Almudena Nunez and Rainer Quitzow♦ France’s Hydrogen Strategy: Focusing on Domestic Hydrogen Production to Decarbonise Industry and Mobility by Ines Bouacida♦ Read More

This study performs a cradle-to-grave life cycle assessment of a 5 MW protonexchange membrane water electrolysis plant. The analysis follows a thoroughengineering-based bottom-up design based on the electrochemical model of thesystem. Three scenarios are analyzed comprising a state-of-the-art (SoA) plantoperated with the German electricity grid-mix a SoA plant operated with acompletely decarbonized energy system and a future develo Read More

Hydrogen produced by renewable energy sources (green hydrogen) is at the centrepiece of European decarbonization strategies necessitating large imports from third countries. Egypt potentially stands out as major production hub. While technical and economic viability are broadly discussed in literature analyses of local acceptance are absent. This study closes this gap by surveying 505 locals in the Suez Canal Economic Zone (Port Said and Suez) regarding Read More

The decarbonization of industrial process heat is one of the bigger challenges of the global energy transition. Process heating accounts for about 20% of final energy demand in Germany and the situation is similar in other industrialized nations around the globe. Process heating is indispensable in the manufacturing processes of products and materials encountered every day ranging from food beverages paper and textiles to metals ceramics glass and cemen Read More

This study identifies supply options for sustainable urban energy systems which are robust to external system changes. A multi-criteria optimization model is used to minimize greenhouse gas (GHG) emissions and financial costs of a reference system. Sensitivity analyses examine the impact of changing boundary conditions related to GHG emissions energy prices energy demands and population density. Options that align with both financial and emission red Read More

Assessing the sustainable development of green hydrogen and assessing its potential environmental impacts using the Life Cycle Assessment is crucial. Challenges in LCA like missing environmental data are often addressed using machine learning such as artificial neural networks. However to find an ML solution researchers need to read extensive literature or consult experts. This research demonstrates how customised LLMs trained with domain-s Read More

Hydrogen is experiencing an unprecedented global hype. Hydrogen is globally discussed as a possible future energy carrier and regarded as the urgently needed building block for the much needed carbon-neutral energy transition of hard-to-abate sectors to mitigate the effects of global warming. This article provides synthesised measurable sustainability criteria for analysing green hydrogen production proposals and strategies. Drawn from expert inte Read More

Salt caverns have great potential to store relevant amounts of hydrogen as part of the energy transition. However the durability and suitability of commonly used steels for piping in hydrogen salt caverns is still under research. In this work aging effects focusing on corrosion and cracking patterns of casing steel API 5CT J55 and “H2ready” pipeline steel API 5L X56 were investigated with scanning electron microscopy and energy dispersive X-ray spectrosco Read More

The measurement of hydrogen concentration in fuel cell systems is an important prerequisite for the development of a control strategy to enhance system performance reduce purge losses and minimize fuel cell aging effects. In this perspective paper the working principles of hydrogen sensors are analyzed and their requirements for hydrogen control in fuel cell systems are critically discussed. The wide measurement range absence of oxygen high humidit Read More

Considerable progress has been made recently in the use of nanoporous materials for hydrogen storage. In this article the current status of the field and future challenges are discussed ranging from important open fundamental questions such as the density and volume of the adsorbed phase and its relationship to overall storage capacity to the development of new functional materials and complete storage system design. With regard to funda Read More

The present work demonstrates a comparative study of hydrogen fuel cells and combustion aircraft to investigate the potential of fuel cells as a visionary propulsion system for radically more sustainable medium- to long-range commercial aircraft. The study which considered future airframe and propulsion technologies under the Se2A project was conducted to quantify potential emissions and costs associated with such aircraft and to determine the b Read More

The high potential of hydrogen as a key factor on the pathway towards a climate neutral economy leads to rising demand in technical applications where gaseous hydrogen is used. For several metals hydrogen-metal interactions could cause a degradation of the material properties. This is especially valid for low carbon and highstrength structural steels as they are commonly used in natural gas pipelines and analyzed in this work. This work provides an Read More

In international regulations on explosion protection mechanical friction impact or abrasion is usually named as one of 13 ignition sources that must be avoided in hazardous zones with explosive atmospheres. In different studies it is even identified as one of the most frequent ignition sources in practice. The effectiveness of mechanical impacts as ignition source is dependent from several parameters including the minimum ignition energy of the explos Read More

The ongoing discourse on the transition to a hydrogen-based economy and the lessons learned from visions such as the Desertec concept emphasise the necessity for a nuanced approach to the development of metrics to assess a country’s hydrogen readiness. In addition to economic criteria such as investment incentives factors including law and order governance performance geography infrastructure and renewable energy production poten Read More

The global push for sustainable energy has heightened the demand for green hydrogen which is crucial for decarbonizing heavy industry. However current electrolysis plant capacities are insufficient. This research addresses the challenge through optimizing large-scale electrolysis construction via standardization modularization process optimization and automation. This paper introduces H2Giga a project for mass-producing electrolyzers and HyPLANT100 in Read More

Climate policy will inevitably lead to the stranding of fossil energy assets such as production and transport assets for coal oil and natural gas. Resourcerich developing countries are particularly aected as they have a higher risk of asset stranding due to strong fossil dependencies and wider societal consequences beyond revenue disruption. However there is only little academic and political awareness of the challenge to manage the asset stranding in these Read More

Hydrogen produced via water electrolysis from renewable electricity is considered a key energy carrier to defossilize hard-to-electrify sectors. Solid oxide cells (SOC) based reactors can supply hydrogen not only in electrolysis but also in fuel cell mode when operating with (synthetic) natural gas or biogas at low conversion (polygeneration mode). However the scale-up of SOC reactors to the multi-MW scale is still a research topic. Strategies for transient op Read More

Technological change is often seen as part of the solution to problems of global sustainability. A wide-ranging literature on how path dependent—often fossil fuel-based—socio-technical configurations can be overcome by more sustainable configurations has emerged over the last two decades. One potential transition pathway to transform electricity heat and mobility systems as well as industrial production is the use of hydrogen. In recent years hydro Read More

By passing the delegated acts supplementing the revised Renewable Energy Directive the European Commission has recently set a regulatory benchmark for the classifcation of green hydrogen in the European Union. Controversial reactions to the restricted power purchase for electrolyser operation refect the need for more clarity about the efects of the delegated acts on the cost and the renewable characteristics of green hydrogen. To resolve this cont Read More

This study offers a comprehensive analysis of the feasibility of green hydrogen economies in Western and Southern African regions focusing on the ECOWAS and SADC countries. Utilizing a novel approach based on composite indicators the research evaluates the potential readiness and overall feasibility of green hydrogen production and export across these regions. The study incorporates various factors including the technical potential of renewable energ Read More

The ongoing global energy transition spurred by ecological concerns and by evolving political dynamics is necessitating a significant expansion of renewable energy sources. This shift towards renewables is introducing the challenge of heightened energy supply volatility and it underscores the imperative for large-scale storage solutions in order to mitigate fluctuations in demand and supply. This study investigates the potential of Power-to-X (P2X) technologie Read More

In this study Distribution of Relaxation Times (DRT) was successfully demonstrated in the analysis of the impedance spectra of High-Temperature Polymer Electrolyte Membrane Fuel Cells (HT-PEMFC) doped with phosphoric acid. Electrochemical impedance spectroscopy (EIS) was performed and the quality of the recorded spectra was verified by Kramers-Kronig relations. DRT was then applied to the measured spectra and polarization losses were separ Read More

Transitioning from fossil fuels to renewable energies is imperative for Germany to reduce CO2 emissions and achieve greenhouse gas neutrality by 2045. Green hydrogen holds great potential to contribute to this energy transition by enabling the storage of surplus renewable energy. However Germany's green hydrogen production industry is still in its infancy with only a few green hydrogen plants existing. Studies examining the public's acceptance of gre Read More

Establishing a climate-neutral energy system is among the most urgent challenges facing humanity with the natural gas network forming a critical component of energy and commodity infrastructure. The hydrogen economy based on climate-neutral hydrogen which serves as both energy source and raw-material for numerous sectors offers a promising pathway for significant reduction in CO2 emissions. However the lack of an extensive hydro Read More

The adoption of liquid hydrogen (LH2) as an energy carrier presents significant opportunities for distributing large quantities of hydrogen efficiently. However ensuring safety of LH2 transfer operations requires the evo lution of suitable technologies and regulatory framework. This study offers an extensive overview of technical considerations and safety aspects pertaining to liquid hydrogen installations and mobile applications. A signif icant lack of regulations Read More

The decarbonization of the building stock in this paper focusing the single-family house sector in Germany is essential to achieve the climate goals. In fact as the largest part of the building stock it represents more than 65 % of the entire German residential building stock. Current strategies and regulations have demonstrated low impact on carbon emission reduction due to poor renovation rates particularly in the single-family house typology. The present Read More

Stringent sustainability goals are set for the next generation of aircraft. A promising novel airframe concept is the ultra-high aspect ratio Strut-Braced Wing (SBW) aircraft. Hydrogen-based concepts are active contenders for sustainable propulsion. The study compares a medium-range Liquid Hydrogen (LH2) to a kerosene-based SBW aircraft designed with the same top-level requirements. For both concepts overall design operating costs and emissions are Read More

This study presents sector-coupled PyPSA-Earth: a novel global open-source energy system optimization model that incorporates major demand sectors and energy carriers in high spatial and temporal resolution to enable energy transition studies worldwide. The model includes a workflow that automatically downloads and processes the necessary demand supply and transmission data to co-optimize investment and operation of energy systems of cou Read More

With green hydrogen gaining traction as a viable sustainable energyoption the present study explores the potential of producing greenhydrogen from wind and solar energy in Ghana. The study combinedthe use of geospatial multi-criteria approach and PEM electrolysisprocess to estimate the geographical and technical potential of theselected two renewable resources. The study also included anassessment of potential areas for grid integration. Technolo Read More

Decarbonizing long-haul heavy-duty transport in Europe focuses on batteryelectric trucks with high-power chargers or electric road systems and fuel-cell-electric vehicles with hydrogen refueling stations. We present a comparative life cycle assessment and total cost of ownership analysis of these technologies for 20% of Germany’s heavy-duty long-haul transport alongside internal combustion engine vehicles. The results show that fuel cell vehicles with o Read More

An important element of modern firefighting is sometimes the use of foam. After the use of extinguishing foam on vehicles or machinery operated by compressed gases it is conceivable that masses of foam were enriched by escaping fuel gas. Furthermore new foam creation enriched with a high level of fuel gas from the deposed foam solution becomes theoretically possible. The aim of this study was to carry out basic experimental investigations Read More

Green hydrogen is a cornerstone in the global quest for a carbon-neutral future offering transformative potential for decarbonizing transportation. This study investigates its role by assessing the feasibility of a large-scale hydrogen refueling station in Germany focusing on integrating renewable energy sources. A hydrogen demand model with a 10-min time resolution to refuel 30 trucks and 20 vans (1019 kg/day) is combined with a techno-economic optimiz Read More

Climate change necessitates the development of sustainable energy systems with hydrogen technologies playing a key role in this transition. Additive manufacturing (AM) offers a significant potential to enhance the efficiency of hydrogen energy components and reduce their costs through rapid prototyping design freedom and functional integration. This review provides the first comprehensive summary of the current state of research on the applicati Read More

Wind power-to-gas concepts have a high potential to sustainably cover the increasing demand for hydrogen as an energy carrier and raw material as it has been shown in the past that there is an enormous potential in energy overproduction which currently remains unused due to the shutdown of wind turbines. Thus there is barely experience in maritime production offshore storage and transport of large quantities of liquid hydrogen (LH2) due to the devel Read More

A real-time on-site monitoring of the concentration of hydrogen and the heating value of a blend of hydrogen and natural gas is of key importance for its safe distribution in existing pipelines as proposed by the ‘Power-toGas’ concept. Although current gas chromatography (PGC) methods deliver this information accurately they are unsuitable for a quick and pipelineintegrated measurement. We analyse the possibility to monitor this blend with a combinatio Read More

Novel hydrogen-based aircraft concepts pose significant challenges for the system development process. This paper proposes a generic adaptable and multidisciplinary framework for integrated model-based systems engineering (MBSE) and model-based safety assessment (MBSA) for the conceptual design of complex systems. The framework employs a multi-granularity modelcentric approach whereby the architectural specification is utilized for desi Read More

The green-hydrogen sector has created considerable expectations in the Global South about export-oriented development and industrial path creation. However whether and how these expectations are really materializing requires further scrutiny. This article develops a conceptual approach that we call governance of futuremaking. Thereby we want to understand how actors try to coordinate their expectations about future economic development Read More

The shipping industry faces the dual challenge of reducing emissions to meet net-zero targets by 2050 and transporting green energy sources like hydrogen and its derivatives. Green shipping corridors provide experimental routes for lowcarbon solutions with the Suez Canal uniquely positioned to lead. This paper examines the canal’s evolving role as a dynamic energy space where diverse actors and networks intersect shaping spatial power relations and ali Read More

Desulphurization of oil-based fuels is common practice to mitigate the ecological burden to ecosystems and human health of SOx emissions. In many countries fuels for vehicles are restricted to 10 ppm sulphur. For marine fuels low sulphur contents are under discussion. The environmental impact of desulphurization processes is however quite high: (1) The main current source for industrial hydrogen is Steam Methane Reforming (SMR) with a r Read More

The H2STORE collaborative project investigates potential geohydraulic petrophysical mineralogical microbiological and geochemical interactions induced by the injection of hydrogen into depleted gas reservoirs and CO2- and town gas storage sites. In this context the University of Jena performs mineralogical and geochemical investigations on reservoir and cap rocks to evaluate the relevance of preferential sedimentological features which will control fluid ( Read More

Hydrogen fuel cell systems are a viable option for electrified aero engines due to their efficiency and environmental benefits. However integrating these systems presents challenges notably in terms of overall system weight and thermal management. Heat exchangers are crucial for the effective thermal management system of electric propulsion systems in commercial electrified aviation. This paper provides a comprehensive review of various hea Read More