Germany

As part of the United Nations’ (UN) Sustainable Development Goal 7 (SDG7) SDG target 7.1 recognizes universal electrification and the provision of clean cooking fuel as two fundamental challenges for global society. Faltering progress toward SDG target 7.1 calls for innovative technologies to stimulate advancements. Hydrogen has been proposed as a versatile energy carrier to be applied in both pillars of SDG target 7.1: electrification and clean Read More

This report from the WP5 “Mitigation” provides information and test results regarding perturbations that hydrogen could cause to gas appliances when blended to natural gas especially on anatural draught for exhaust fumes or acidity for the condensates. The important topic of on-site adjustment is also studied with test results on alternative technologies and proposals of mitigation approaches.

The realization of a carbon-neutral civilization which has been set as a goal for the coming decades goes directly hand-in-hand with the need for an energy system based on renewable energies (REs). Due to the strong weather-related daily and seasonal fluctuations in supply of REs suitable energy storage devices must be included for such energy systems. For this purpose an energy system model featuring hybrid energy storage consisting of a hydr Read More

Especially the electrification of the industry sector is highly complex and challenging mainly due to process-specific requirements. In this context there are several industrial processes where the direct and indirect use of electricity is subject to technical restrictions. In order to achieve the national climate goals the fossil energy consumption remaining after the implementation of efficiency and sufficiency measures as well as direct electrification has to be Read More

At the heart of most Power-to-X (PtX) concepts is the utilization of renewable electricity to produce hydrogen through the electrolysis of water. This hydrogen can be used directly as a final energy carrier or it can be converted into for example methane synthesis gas liquid fuels electricity or chemicals. Technical demonstration and systems integration are of major importance for integrating PtX into energy systems. As of June 2020 a total of 220 PtX resear Read More

Jet flames originated by cryo-compressed ignited hydrogen releases can cause life-threatening conditions in their surroundings. Validated models are needed to accurately predict thermal hazards from a jet fire. Numerical simulations of cryogenic hydrogen flow in the release pipe are performed to assess the effect of heat transfer through the pipe walls on jet parameters. Notional nozzle exit diameter is calculated based on the simulated real nozzle paramete Read More

A series of more than 100 experiments with hydrogen-air mixtures at cryogenic temperatures have been performed in a shock tube in the frame of the PRESLHY project. A wide range of hydrogen concentrations from 8 to 60%H2 in the shock tube of the length of 5 m and 50 mm id was tested at cryogenic temperatures from 80 to 130K at ambient pressure. Flame propagation regimes were investigated for all hydrogen compositions in the shock tub Read More

With the rising threat of climate change green hydrogen is increasingly seen as the high-capacity energy storage and transport medium of the future. This creates an opportunity for low- and middle-income countries to leverage their high renewable energy potential to produce use and export low-cost green hydrogen creating environmental and economic development benefits. While identifying ideal locations for green hydrogen production is critical f Read More

The European Union’s target to reach greenhouse gas neutrality by 2050 calls for a sharp decrease in the consumption of natural gas. This study assesses impacts of greenhouse gas neutrality on the gas system taking France and Germany as two case studies which illustrate a wide range of potential developments within the European Union. Based on a review of French and German GHG-neutral scenarios it explores impacts on gas infrastructu Read More

The rising demand for energy and the aim of moving away from fossil fuels and to low-carbon power have led many countries to move to alternative sources including solar energy wind geothermal energy biomass and hydrogen. Hydrogen is often considered a “missing link” in guaranteeing the energy transition providing storage and covering the volatility and intermittency of renewable energy generation. However due to potential injustice with regard to t Read More

The measures needed to limit global warming pose a particular challenge to current fossil fuel exporters who must not only decarbonise their local energy systems but also compensate for the expected decline in fossil fuel revenues. One possibility is seen in the export of green hydrogen. Using Algeria as a case study this paper analyses how different levels of ambition in hydrogen exports energy efficiency and fuel switching affect the costoptimal expansio Read More

Green hydrogen promises to be critical in achieving a sustainable and renewable energy transition. As green hydrogen is produced with renewables green hydrogen could become an energy storage medium of the future and even substitute the current unsustainable grey or blue hydrogen used in the industry. Bringing this transition into reality for instance in Germany there are visions to rapidly build hydrogen facilities in Africa and export the produced g Read More

Globally a green hydrogen economy rush is underway and many companies investors governments and environmentalists consider it as an energy source that could foster the global energy transition. The enormous potential for hydrogen production for domestic use and export places Africa in the spotlight in the green hydrogen economy discourse. This discourse remains unsettled regarding how natural resources such as land and water can be sustain Read More

Subcooled liquid hydrogen (sLH2) is an onboard storage as well as a hydrogen refueling technology that is currently being developed by Daimler Truck and Linde to boost the mileage of heavy-duty trucks while also improving performance and reducing the complexity of hydrogen refueling stations. In this article the key technical aspects advantages challenges and future developments of sLH2 at vehicle and infrastructure levels will be explored and highlighted.

This work evaluates the effectiveness of chemical-based solutions for storing large amounts of renewable electricity. Four “Power-to-X-to-Power” pathways are examined comprising hydrogen methane methanol and ammonia as energy carriers. The pathways are assessed using a model scenario where they are produced with electricity from an onshore wind farm stored in suitable facilities and then reconverted to electricity to meet the energy demand of Read More

Cryogenic liquid is often stored in a vacuum insulated Dewar vessel for a high efficiency of thermal insulation. Multi-layer insulation (MLI) can be further applied in the double-walled vacuum space to reduce the heat transfer from the environment to the stored cryogenic fluid. However in loss-of-vacuum accident (LOVA) scenarios heat flux across the MLI will raise to orders of magnitudes larger than with an intact vacuum shield. The cryogenic liquid Read More

This review article deals with the challenge to identify catalyst materials from literature studies for the ammonia decomposition reaction with potential for application in large-scale industrial processes. On the one hand the requirements on the catalyst are quite demanding. Of central importance are the conditions for the primary reaction that have to be met by the catalyst. Likewise the catalytic performance i.e. an ideally quantitative conversion a Read More

Hydrogen as a carbon-free energy carrier has emerged as a crucial component in the decarbonization of the energy system serving as both an energy storage option and fuel for dispatchable power generation to mitigate the intermittent nature of renewable energy sources. However the unique physical and combustion characteristics of hydrogen which differ from conventional gaseous fuels such as biogas and natural gas present new challenges that Read More

The need to drastically reduce greenhouse gas emissions is driving the development of existing and new technologies to produce and use hydrogen. Anion exchange membrane electrolysis is one of these rapidly developing technologies and presents promising characteristics for efficient hydrogen production. However the environmental performance and the material criticality of anion exchange membrane electrolysis must be assessed. In this work pro Read More

The production of fat steel products is commonly linked to highly integrated sites which include hot metal generation via the blast furnace basic oxygen furnace (BOF) continuous casting and subsequent hot-rolling. In order to reach carbon neutrality a shift away from traditional carbon-based metallurgy is required within the next decades. Direct reduction (DR) plants are capable to support this transition and allow even a stepwise reduction in CO2 e Read More

In a future energy generation market the storage of energy is going to become increasingly important. Besides classic ways of storage like pumped storage hydro power stations etc the production of hydrogen will play an important role as an energy storage system. Hydrogen may be stored as a liquefied gas (LH2) on a long term base as well as for short term supply of fuel stations to ensure a so called “green” mobility. The handling with LH2 has been s Read More

In case of accidental conditions involving high-speed hydrogen combustion the considerable pressure and thermal loads could result in substantial deformation and/or destruction of the industrial appliances. Accounting of such effects in the safety analysis with CFD tools can provide critical information on the design and construction of the sensitive appliances’ elements. The current paper presents the development and the implementation of a new Read More

Green hydrogen is a promising alternative to fossil fuels. However current production capacities for electrolyzers and green hydrogen are not in line with national political goals and projected demand. Considering these issues we conducted semi-structured interviews to determine the narratives of different stakeholders during this transformation as well as challenges and opportunities for the green hydrogen value chain. We interviewed eight experts Read More

High fluctuations in the combustion process from one cycle to another referred to as cycle-by-cycle variations can have adverse effects on internal combustion engine performances particularly in spark ignition (SI) engines. These effects encompass incomplete combustion the potential for misfires and adverse impacts on fuel economy. Furthermore the cycle-by-cycle variations can also affect a vehicle’s drivability and overall comfort especially w Read More

The global green hydrogen rush is prone to repeat extractivist patterns at the expense of economies ecologies and communities in the production zones in the Global South. With a socio-ecological risk analysis grounded in energy water and environmental justice scholarship we systematically assess the risks of the ‘green’ hydrogen transition and related injustices arising in 28 countries in the Global South with regard to energy water land and global justic Read More