Switzerland

External magnetic fields affect various electrochemical processes and can be used to enhance the efficiency of the electrochemical water splitting reaction. However the driving forces behind this effect are poorly understood due to the analytical challenges of the available interface-sensitive techniques. Here we present a set-up based on magneto- and electro-optical probing which allows to juxtapose the magnetic properties of the electrode with the electr Read More

Power-to-fuel systems via solid-oxide electrolysis are promising for storing excess renewable electricity by efficient electrolysis of steam (or co-electrolysis of steam and CO2) into hydrogen (or syngas) which can be further converted into synthetic fuels with plant-wise thermal integration. Electrolysis stack performance and durability determine the system design performance and long-term operating strategy; thus solid-oxide electrolyzer based powe Read More

This study presents an integrated techno-environmental assessment of hydrogen production from natural gas and biomethane combined with CO2 capture and storage (CCS). We have included steam methane reforming (SMR) and autothermal reforming (ATR) for syngas production. CO2 is captured from the syngas with a novel vacuum pressure swing adsorption (VPSA) process that combines hydrogen purification and CO2 separation in one cycle. As c Read More

Structural integrity of reactor pressure vessel (RPV) in light water reactors (LWR) is of highest importance regarding operation safety and lifetime. The fracture behaviour of low-alloy RPV steels with different dynamic strain aging (DSA) & environmental assisted cracking (EAC) susceptibilities in simulated LWR environments was evaluated by elastic plastic fracture mechanics tests (EPFM) and by metallo- and fractographic post-test analysis. Exposure to h Read More

The role of hydrogen in future energy systems is widely acknowledged: from fuel for difficult-to-decarbonize applications to feedstock for chemicals synthesis to energy storage for high penetration of undispatchable renewable electricity. While several literature studies investigate such energy systems the details of how electrolysers and renewable technologies optimally behave and interact remain an open question. With this work we study the interplay betw Read More

This study investigates the optimal design of low-carbon hydrogen supply chains on a national scale. We consider hydrogen production based on several feedstocks and energy sources namely water with electricity natural gas and biomass. When using natural gas we couple hydrogen production with carbon capture and storage. The design of the hydrogen biomass and carbon dioxide (CO2 ) infrastructure is performed by solving an optimization proble Read More

Achieving climate-neutrality requires considerable investment in energy storage systems (ESS) to integrate variable renewable energy sources into the grid. However investments into ESS are often unprofitable in particular for grid-scale battery storage and green hydrogen technologies prompting many actors to call for policy intervention. This study investigates investor-specific risk-return preferences for ESS investment and derives policy recommendation Read More

This work presents a detailed breakdown of the energy conversion chains from intermittent electricity to a vehicle considering battery electric vehicles (BEVs) and fuel cell electric vehicles (FCEVs). The traditional well-to-wheel analysis is adapted to a grid to mobility approach by introducing the intermediate steps of useful electricity energy carrier and on-board storage. Specific attention is given to an effective coupling with renewable electricity sources and as Read More

In this analysis life cycle environmental burdens and total costs of ownership (TCO) of current (2017) and future (2040) passenger cars with different powertrain configurations are compared. For all vehicle configurations probability distributions are defined for all performance parameters. Using these a Monte Carlo based global sensitivity analysis is performed to determine the input parameters that contribute most to overall variability of results. Read More

Solar-hydrogen generation represents a promising alternative to fossil fuels for the large-scale implementation of a clean-fuel transportation infrastructure. A significant amount of research resources has been allocated to the development of photoelectrochemical components (i.e. photovoltaic and water splitting catalysts) that are able to spontaneously split water in the presence of solar irradiation which has led to major advances in the solar-fuels field. At Read More

The performance of four Coriolis flow meters designed for use in hydrogen refuelling stations was evaluated with air and nitrogen by three members of the MetroHyVe JRP consortium; NEL METAS and CESAME EXADEBIT.A wide range of conditions were tested overall with gas flow rates ranging from (0.05–2) kg/min and pressures ranging from (20–86) bar. The majority of tests were conducted at nominal pressures of either 20 bar or 40 bar in order to Read More

Electrifying energy-intensive processes is currently intensively explored to cut greenhouse gas (GHG) emissions through renewable electricity. Electrification is particularly challenging if fossil resources are not only used for energy supply but also as feedstock. Copper production is such an energy-intensive process consuming large quantities of fossil fuels both as reducing agent and as energy supply.Here we explore the techno-economic potential of Power-to Read More

In view of the recent interest in the transformation of renewable energy into a new energy vector that did not produce by combustion greenhouse gases emissions the Fuel Cells and Hydrogen Joint Undertaking (FCH JU) commissioned this report to a con­sultancy to get a better understanding of the industrial perspectives of water electrolysis in Europe. and the role that public support has in that evolution.

The synthesis of a Substitute Natural Gas (SNG) that is compatible with the gas grid composition requirements by using surplus electricity from renewable energy sources looks a favourable solution to store large quantities of electricity and to decarbonise the gas grid network while maintaining the same infrastructure. The most promising layouts for SNG production and the conditions under which SNG synthesis reduces the environmental impacts i Read More

Synthetic fuels produced with renewable surplus electricity depict an interesting solution for the decarbonization of mobility and transportation applications which are not suited for electrification. With the objective to compare various synthetic fuels an analysis of all the energy conversion steps is conducted from the electricity source i.e. wind- solar- or hydro-power to the final application i.e. a vehicle driving a certain number of miles. The investigated fuels Read More

Hydrogen as an energy carrier is very versatile in energy storage applications. Developments in novel sustainable technologies towards a CO2-free society are needed and the exploration of all-solid-state batteries (ASSBs) as well as solid-state hydrogen storage applications based on metal hydrides can provide solutions for such technologies. However there are still many technical challenges for both hydrogen storage material and ASSBs related to design Read More

Low-carbon hydrogen is an essential element in the transition to net-zero emissions by 2050. Hydrogen production from biomass is a promising bio-energy with carbon capture and storage (BECCS) scheme that could produce low-carbon hydrogen and generate the carbon dioxide removal (CDR) envisioned to be required to offset hard-to-abate emissions. Here we design a BECCS supply chain for hydrogen production from biomass with carbon capture and Read More

Since the beginning of the twenty-first century the limitations of the fossil age with regard to the continuing growth of energy demand the peaking mining rate of oil the growing impact of CO2 emissions on the environment and the dependency of the economy in the industrialized world on the availability of fossil fuels became very obvious. A major change in the energy economy from fossil energy carriers to renewable energy fluxes is necessary. The main Read More

We analytically investigated the influence of light hydrocarbons on turbulent premixed H2/air atmospheric flames under lean conditions in view of safe handling of H2 systems applications in H2 powered IC engines and gas turbines and also with an orientation towards modelling of H2 combustion. For this purpose an algebraic flame surface wrinkling model included with pressure and fuel type effects is used. The model predictions of turbulent premi Read More

The present work aims to identify critical materials in water electrolysers with potential future supply constraints. The expected rise in demand for green hydrogen as well as the respective implications on material availability are assessed by conducting a case study for Germany. Furthermore the recycling of end‐of‐life (EoL) electrolysers is evaluated concerning its potential in ensuring the sustainable supply of the considered materials. As critical materi Read More

Biomass gasification is a promising technology to produce secondary fuels or heat and power offering considerable advantages over fossil fuels. An important aspect in the usage of producer gas is the removal of harmful contaminants from the raw syngas. Thus the object of this study is the development of a simulation model for a gasifier including gas clean-up for which a fluidized-bed gasifier for biomass-derived syngas production was considered bas Read More

In order to achieve gradual but timely decarbonisation of the transport sector it is essential to evaluate which types of vehicles provide a suitable environmental performance while allowing the use of hydrogen as a fuel. This work compares the environmental life-cycle performance of three different passenger cars fuelled by hydrogen: a fuel cell electric vehicle an internal combustion engine car and a hybrid electric vehicle. Besides two vehicle Read More

Hydrogen has been identified as a potential energy vector to decarbonise the transport and chemical sectors and achieve global greenhouse gas reduction targets. Despite ongoing efforts hydrogen technologies are often assessed focusing on their global warming potential while overlooking other impacts or at most including additional metrics that are not easily interpretable. Herein a wide range of alternative technologies have been assessed to determi Read More

A large deployment of energy storage solutions will be required by the stochastic and non-controllable nature of most renewable energy sources when planning for higher penetration of renewable electricity into the energy mix. Various solutions have been suggested for dealing with medium- and long-term energy storage. Hydrogen and ammonia are two of the most frequently discussed as they are both carbon-free fuels. In this paper the authors an Read More

This work focuses on tests for control reserve of a novel Power-to-Gas-to-Power platform based on proton exchange membrane technologies and on pure oxygen instead of air in the re-electrification process. The technologies are intended as a further option to stabilize the power system therefore helping integrating renewable energy into the power system. The tests are based on the pre-qualification tests used by Swissgrid but are not identical in o Read More

This paper describes a generic and systematic method to calculate the efficiency and the annual performance for Power-to-Gas (PtG) systems. This approach gives the basis to analytically compare different PtG systems using different technologies under different boundary conditions. To have a comparable basis for efficiency calculations a structured break down of the PtG system is done. Until now there has not been a universal approach for efficiency calcula Read More

This study analyzes the factors leading to the deployment of Power-to-Hydrogen (PtH2) within the optimal design of district-scale Multi-Energy Systems (MES). To this end we utilize an optimization framework based on a mixed integer linear program that selects sizes and operates technologies in the MES to satisfy electric and thermal demands while minimizing annual costs and CO2 emissions. We conduct a comprehensive uncertainty analysis that encompa Read More

Europe’s low-carbon energy policy favors a greater use of fuel cells and technologies based on hydrogen used as a fuel. Hydrogen delivered at the hydrogen refueling station must be compliant with requirements stated in different standards. Currently the quality control process is performed by offline analysis of the hydrogen fuel. It is however beneficial to continuously monitor at least some of the contaminants onsite using chemical sensors. For hydrogen Read More

The classical approach to use hydrogen as a fuel for Internal Combustion Engines (ICEs) is premixed combustion. In order to avoid knocking and to limit NOx emissions very lean mixtures are employed thus resulting in a high boost pressure demand or low specific engine power. To overcome these limitations the possibility of a diesellike jet-guided combustion of hydrogen is explored. The approach is to ignite a directly injected hydrogen jet at its periphery b Read More

A new electrically driven gas booster is described as an alternative to the classical air-driven gas boosters known for their poor energetic efficiency. These boosters are used in small scale Hydrogen storage facilities and in refueling stations for Hydrogen vehicles. In such applications the overall energy count is of significance and must include the efficiency of the compression stage. The proposed system uses an electric motor instead of the pneumatic actu Read More

Noble metals are added to boiling water reactors (BWRs) to mitigate stress corrosion cracking of structural components made from steels and Ni-based alloys and this technology is referred to as Noble Metal Chemical Addition (NMCA) or NobleChemTM. There is a growing concern that NMCA can cause unwanted harmful effects on the corrosion and hydrogen uptake properties of Zircaloy-2 fuel cladding. To investigate this we have subjected Zircal Read More

The depletion of fossil fuel sources has encouraged the authorities to use renewable resources such as wind energy to generate electricity. A backup/storage system can improve the performance of wind turbines due to fluctuations in power demand. The novelty of this study is to utilize a hybrid system for a wind farm using the excess electricity generated by the wind turbines to produce hydrogen in an alkaline electrolyzer (AEL). The hydrogen storage tank Read More

The world-wide sustainability implications of transport technologies remain unclear because their assessment often relies on metrics that are hard to interpret from a global perspective. To contribute to filling this gap here we apply the concept of planetary boundaries (PBs) i.e. a set of biophysical limits critical for operating the planet safely to address the optimal design of sustainable fuel supply chains (SCs) focusing on hydrogen for vehicle use. B Read More

The liquid hydrogen demand particularly driven by clean energy applications will rise in the near future. As industrial large scale liquefiers will play a major role within the hydrogen supply chain production capacity will have to increase by a multiple of today’s typical sizes. The main goal is to reduce the total cost of ownership for these plants by increasing energy efficiency with innovative and simple process designs optimized in capital expenditure. New co Read More

Green hydrogen allows coupling renewable electricity to hard-to-decarbonize sectors such as long-distance transport and carbon-intensive industries in order to achieve net zero emissions. Evaluating the cost and value of power-to-gas is a major challenge owing to the spatial distribution and temporal variability of renewable electricity CO2 and energy demand. Here we propose a method based on geographic information system (GIS) and techno-economic Read More

About 25 years ago Bogdanovic and Schwickardi (B. Bogdanovic M. Schwickardi: J. Alloys Compd. 1–9 253 (1997) discovered the catalyzed release of hydrogen from NaAlH4 . This discovery stimulated a vast research effort on light hydrides as hydrogen storage materials in particular boron hydrogen compounds. Mg(BH4 )2 with a hydrogen content of 14.9 wt % has been extensively studied and recent results shed new light on intermediate spec Read More

This research investigated the suitability of air-to-water generator (AWG) technology to address one of the main concerns in green hydrogen production namely water supply. This study specifically addresses water quality and energy sustainability issues which are crucial research questions when AWG technology is intended for electrolysis. To this scope a reasoned summary of the main findings related to atmospheric water quality has been prov Read More

The hydrogen combustion engine (H2 ICE) is known to be able to burn H2 producing no CO2 emissions and extremely low engine-out NOeo emissions. In this work the potential to reduce the NOeo emissions through the implementation of electric hybridization of an H2 ICE-equipped passenger car (H2 -HEV) combined with a dedicated energy management system (EMS) is discussed. Achieving a low H2 consumption and low NOeo emissions are conflicti Read More

Hydrogen is receiving increasing attention to decarbonize hard-to-abate sectors such as carbon intensive industries and long-distance transport with the ultimate goal of reducing greenhouse gas (GHG) emissions to net-zero. However limited knowledge exists so far on the socio-economic and environmental impacts for countries moving towards green hydrogen. Here we analyse the macroeconomic impacts both direct and indirect in terms of GDP gro Read More

The last twenty years of an intense research on metal hydroborates as solid hydrogen stores and solid electrolytes are reviewed. It is shown that from the most promising application in hydrogen storage due to their high gravimetric and volumetric capacities the focus has moved to solid electrolytes due to high cation mobility in disordered structures with rotating or tumbling anions-hydroborate clusters. Various strategies of overcoming the strong covalen Read More

Natural gas based hydrogen production with carbon capture and storage is referred to as blue hydrogen. If substantial amounts of CO2 from natural gas reforming are captured and permanently stored such hydrogen could be a low-carbon energy carrier. However recent research raises questions about the effective climate impacts of blue hydrogen from a life cycle perspective. Our analysis sheds light on the relevant issues and provides a balanced p Read More

Solar energy provides an unprecedented potential as a renewable and sustainable energy resource and will substantially reshape our future energy economy. It is not only useful in producing electricity but also (hightemperature) heat and fuel both required for non-electrifiable energy services. Fuels are particularly valuable as they are energy dense and storable and they can also act as a feedstock for the chemical industry. Technical pathways for the process Read More

Water electrolysis is a promising approach to hydrogen production from renewable energy sources. Alkaline water electrolyzers allow using non-noble and low-cost materials. An analysis of common assumptions and experimental conditions (low concentrations low temperature low current densities and short-term experiments) found in the literature is reported. The steps to estimate the reaction overpotentials for hydrogen and oxygen reactions are re Read More

In the framework of the ongoing EMPIR JRP 16ENG01 ‘‘Metrology for Hydrogen Vehicles’’ a main task is to investigate the influence of pressure on the measurement accuracy of Coriolis Mass Flow Meters (CFM) used at Hydrogen Refueling Stations (HRS). At a HRS hydrogen is transferred at very high and changing pressures with simultaneously varying flow rates and temperatures. It is clearly very difficult for CFMs to achieve the current legal requir Read More

The cost of polymer electrolyte water electrolysis (PEWE) is dominated by the price of electricity used to power the water splitting reaction. We present a liquid water fed polymer electrolyte water electrolyzer cell operated at a cell temperature of 100 °C in comparison to a cell operated at state-of-the-art operation temperature of 60 °C over a 300 h constant current period. The hydrogen conversion efficiency increases by up to 5% at elevated temp Read More

The Federal Institute of Metrology METAS developed a Hydrogen Field Test Standard (HFTS) that can be used for field verification and calibration of hydrogen refuelling stations. The testing method is based on the gravimetric principle. The experimental design of the HFTS as well as the description of the method are presented here.

Although polymer electrolyte water electrolyzers (PEWEs) have been used in small-scale (kW to tens of kW range) applications for several decades PEWE technology for hydrogen production in energy applications (power-to-gas power-to-fuel etc.) requires significant improvements in the technology to address the challenges associated with cost performance and durability. Systems with power of hundreds of kW or even MWs corresponding to hydrogen p Read More

Low-carbon (green) hydrogen can be generated via water electrolysis using photovoltaic wind hydropower or decarbonized grid electricity. This work quantifies current and future costs as well as environmental burdens of large-scale hydrogen production systems on geographical islands which exhibit high renewable energy potentials and could act as hydrogen export hubs. Different hydrogen production configurations are examined considering a dai Read More

The automotive industry is undergoing a profound transformation driven by the need for sustainable and environmentally friendly transportation solutions [1]. In this context fuel cell technology has emerged as a promising alternative offering clean efficient and high-performance power sources for vehicles [2]. Fuel cell vehicles are electric vehicles that use fuel cell systems as a single power source or as a hybrid power source in combination with rechargeable Read More

Several countries have revised their targets in recent years to reach net-zero CO2 emissions across all sectors by 2050 and the transport sector is responsible for a significant share of these emissions. This study compares possible pathways to decarbonise the transport sector through electrification including passenger cars light commercial vehicles and heavy commercial vehicles. To do so we explore 125 scenarios by varying the share of bat Read More