Switzerland

A redox dual-flow battery is distinct from a traditional redox flow battery (RFB) in that the former includes a secondary energy platform in which the pre-charged electrolytes can be discharged in external catalytic reactors through decoupled redox-mediated hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The concept offers several advantages over conventional electrolysis in terms of safety durability modularity and purity. In this work we demonstrate a vanadium-manganese redox-flow battery in which Mn3+/Mn2+ and V3+/V2+ respectively mediate the OER and the HER in Mo2C-based and RuO2-based catalysts. The flow battery demonstrates an average energy efficiency of 68% at a current density of 50 mA ⋅ cm−2 (cell voltage = 1.92 V) and a relative energy density 45% higher than the conventional all-vanadium RFB. Both electrolytes are spontaneously discharged through redox-mediated HER and OER with a faradic efficiency close to 100%.

The urgency to achieve net-zero carbon dioxide (CO2) emissions by 2050 as first presented by the IPCC special report on 1.5°C Global Warming has spurred renewed interest in hydrogen to complement electrification for widespread decarbonization of the economy. We present reflections on estimates of future hydrogen demand optimization of infrastructure for hydrogen production transport and storage development of viable business cases and environmental impact evaluations using life cycle assessments. We highlight challenges and opportunities that are common across studies of the business cases for hydrogen in Germany the UK the Netherlands Switzerland and Norway. The use of hydrogen in the industrial sector is an important driver and could incentivise large-scale hydrogen value chains. In the long-term hydrogen becomes important also for the transport sector. Hydrogen production from natural gas with capture and permanent storage of the produced CO2 (CCS) enables large-scale hydrogen production in the intermediate future and is complementary to hydrogen from renewable power. Furthermore timely establishment of hydrogen and CO2 infrastructures serves as an anchor to support the deployment of carbon dioxide removal technologies such as direct air carbon capture and storage (DACCS) and biohydrogen production with CCS. Significant public support is needed to ensure coordinated planning governance and the establishment of supportive regulatory frameworks which foster the growth of hydrogen markets.

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 processing of solar fuels include thermal pathways (e.g. solar thermochemistry) photo pathways (e.g. photoelectrochemistry) and combinations thereof. A review of theoretical limits indicates that all technical solar fuel processing pathways have the potential for competitive solar-to-fuel efficiencies (>10 %) but require very different operating conditions (e.g. temperature levels or oxygen partial pressures) making them complementary and highly versatile for process integration. Progress in photoelectrochemical devices and solar thermochemical reactors over the last 50 + years are summarized showing encouraging trends in terms of performance technological viability and scaling.

This paper analyzes the operation of an energy hub on a community level with an integrated P2X facility and with access to energy markets. In our case P2X allows converting power to hydrogen heat methane or back to power. We consider the energy hub as a large prosumer who can be both a producer and consumer in the markets with the novelty that P2X technology is available. We investigate how such a P2X energy hub trades optimally in the electricity market and satisfies local energy demand under the assumption of a long-term strong climate scenario in year 2050. For numerical analysis a case study of a mountain village in Switzerland is used. One of the main contributions of this paper is to quantify key conditions for profitable operations of such a P2X energy hub. In particular the analysis includes impacts of influencing factors on profits and operational patterns in terms of different degrees of self-sufficiency and different availability of local renewable resources. Moreover the access to real-time wholesale market electricity price signals and a future retail hydrogen market is assessed. The key factors for the successful operation of a P2X energy hub are identified to be sufficient local renewable resources and access to a retail market of hydrogen. The results also show that the P2X operation leads to an increased deployment of local renewables especially in the case of low initial deployment; on the other hand seasonal storage plays a subordinated role. Additionally P2X lowers for the community the wholesale electricity market trading volumes.

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 actuator and increases the total efficiency of the compression process. Two mechanical principles are studied for the transformation of the rotational motion of the motor to the linear displacement of the compressor pistons. The strongly fluctuating power of the compressor is smoothed by an active capacitive auxiliary storage device connected to the DC circuit of the power converter. The proposed system has been verified by numeric simulation including the thermodynamic phenomena the kinetics of the new compressor drive and the the operation of the circuits of the power smoothing system.

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 order to capture the maximum dynamics by the plants. The main characteristics identified are the ramping capabilities of ±8% per unit per second for the electrolyzer system and ±33% per unit per second for the fuel cell system. The ramping capabilities are mainly limited by the underlying processes of polymer electrolyte membrane technologies. Additionally the current and projected round-trip efficiencies for Power-to-Gas-to-Power of 39% in 2025 and 48% in 2040 are derived. Furthermore during the successful tests the usage of oxygen in the present Power-to-Gas and Gas-to-Power processes and its influence on the dynamics and the round-trip efficiency was assessed. In consequence fundamental data on the efficiency and the dynamics of the Power-to-Gas-to-Power technologies is presented. This data can serve as basis for prospective assessments on the suitability of the technologies investigated for frequency control in power systems.

Current technological improvements are yet to put the world on track to net-zero which will require the uptake of transformative low-carbon innovations to supplement mitigation efforts. However the role of such innovations is not yet fully understood; some of these ‘miracles’ are considered indispensable to Paris Agreement-compliant mitigation but their limitations availability and potential remain a source of debate. We evaluate such potentially game-changing innovations from the experts’ perspective aiming to support the design of realistic decarbonisation scenarios and better-informed net-zero policy strategies. In a worldwide survey 260 climate and energy experts assessed transformative innovations against their mitigation potential at-scale availability and/or widescale adoption and risk of delayed diffusion. Hierarchical clustering and multi-criteria decision-making revealed differences in perceptions of core technological innovations with next generation energy storage alternative building materials iron-ore electrolysis and hydrogen in steelmaking emerging as top priorities. Instead technologies highly represented in well-below-2◦C scenarios seemingly feature considerable and impactful delays hinting at the need to re-evaluate their role in future pathways. Experts’ assessments appear to converge more on the potential role of other disruptive innovations including lifestyle shifts and alternative economic models indicating the importance of scenarios including non-technological and demand-side innovations. To provide insights for expert elicitation processes we finally note caveats related to the level of representativeness among the 260 engaged experts the level of their expertise that may have varied across the examined innovations and the potential for subjective interpretation to which the employed linguistic scales may be prone to.

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 concepts must ensure a manageable plant complexity and flexible operability. In the phase of process development and selection a dimensioning of key equipment for large scale liquefiers such as turbines and compressors as well as heat exchangers must be performed iteratively to ensure technological feasibility and maturity. Further critical aspects related to hydrogen liquefaction e.g. fluid properties ortho-para hydrogen conversion and coldbox configuration must be analysed in detail. This paper provides an overview on the approach challenges and preliminary results in the development of efficient as well as economically viable concepts for large-scale hydrogen liquefaction.

The deployment of diverse energy storage technologies with the combination of daily weekly and seasonal storage dynamics allows for the reduction of carbon dioxide (CO₂) emissions per unit energy provided. In particular the production storage and re-utilization of hydrogen starting from renewable energy has proven to be one of the most promising solutions for offsetting seasonal mismatch between energy generation and consumption. A realistic possibility for large-scale hydrogen storage suitable for long-term storage dynamics is presented by salt caverns. In this contribution we provide a framework for modelling underground hydrogen storage with a focus on salt caverns and we evaluate its potential for reducing the CO₂ emissions within an integrated energy systems context. To this end we develop a first-principle model which accounts for the transport phenomena within the rock and describes the dynamics of the stored energy when injecting and withdrawing hydrogen. Then we derive a linear reduced order model that can be used for mixed-integer linear program optimization while retaining an accurate description of the storage dynamics under a variety of operating conditions. Using this new framework we determine the minimum-emissions design and operation of a multi-energy system with H₂ storage. Ultimately we assess the potential of hydrogen storage for reducing CO₂ emissions when different capacities for renewable energy production and energy storage are available mapping emissions regions on a plane defined by storage capacity and renewable generation. We extend the analysis for solar- and wind-based energy generation and for different energy demands representing typical profiles of electrical and thermal demands and different CO₂ emissions associated with the electric grid.

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 based on a quasi-equilibrium approach through Gibbs free energy minimisation and including an innovative hot gas cleaning constituted by a combination of catalyst sorbents inside the gasification reactor catalysts in the freeboard and subsequent sorbent reactors by using Aspen Plus software. The gas cleaning chain simulates the raw syngas clean-up for several organic and inorganic contaminants i.e. toluene benzene naphthalene hydrogen sulphide hydrogen chloride and ammonia. The tar and inorganic contaminants final values achieved are under 1 g/Nm3 and 1 ppm respectively.

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 covalent bonding of hydrogen in hydroborates for hydrogen storage and disordering their structures at room temperature for solid electrolytes are discussed. The important role of crystal chemistry and crystallography knowledge in material design can be read in the cited literature.

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 if compared to its fossil alternative is still largely untapped. In this work six different layouts for the production of SNG and electricity from biomass and fluctuating electricity are compared from the environmental point of view by means of Life Cycle Assessment (LCA) methodology. Global Warming Potential (GWP) Cumulative Energy Demand (CED) and Acidification Potential (AP) are selected as impact indicators for this analysis. The influence of key LCA methodological aspects on the conclusions is also explored. In particular two different functional units are chosen: 1 kg of SNG produced and 1 MJ of output energy (SNG and electricity). Furthermore different approaches dealing with co-production of electricity are also applied. The results show that the layout based on hydrogasification has the lowest impacts on all the considered cases apart from the GWP and the CED with SNG mass as the functional unit and the avoided burden approach. Finally the selection of the multifunctionality approach is found to have a significant influence on technology ranking.

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 storage and quantify at high spatial resolution the technical potential for hydrogen production and CDR in Europe. We consider sustainable biomass feedstocks that have minimal impacts on food security and biodiversity namely agricultural residues and waste. We find that this BECCS supply chain can produce up to 12.5 Mtons of H2 per year (currently ~10 Mtons of H2 per year are used in Europe) and remove up to 133 Mtons CO2 per year from the atmosphere (or 3% of European total greenhouse gas emissions). We then perform a geospatial analysis to quantify transportation distances between where biomass feedstocks are located and potential hydrogen users and find that 20% of hydrogen potential is located within 25 km from hard-toelectrify industries. We conclude that BECCS supply chains for hydrogen production from biomass represent an overlooked near-term opportunity to generate carbon dioxide removal and low-carbon hydrogen.

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 determine the total cost of hydrogen production by coupling life-cycle assessments with an economic evaluation of the environmental externalities of production. By including monetised values of environmental impacts on human health ecosystem quality and resources on top of the levelised cost of hydrogen production an estimation of the “real” total cost of hydrogen was obtained to transparently rank the alternative technologies. The study herein covers steam methane reforming (SMR) coal and biomass gasification methane pyrolysis and electrolysis from renewable and nuclear technologies. Monetised externalities are found to represent a significant percentage of the total cost ultimately altering the standard ranking of technologies. SMR coupled with carbon capture and storage emerges as the cheapest option followed by methane pyrolysis and water electrolysis from wind and nuclear. The obtained results identify the “real” ranges for the cost of hydrogen compared to SMR (business as usual) by including environmental externalities thereby helping to pinpoint critical barriers for emerging and competing technologies to SMR.

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-Hydrogen to decarbonize copper production. To determine the minimal cost of an on-site retrofit with Power-to-Hydrogen technology we formulate and solve a mixed-integer linear program for the integrated system. Under current techno-economic parameters for Germany the resulting direct CO₂ abatement cost is 201 EUR/t CO₂-eq for Power-to-Hydrogen in copper production. On-site utilization of the electrolysis by-product oxygen has a substantial economic benefit. While the abatement cost vastly exceeds current European emission certificate prices a sensitivity analysis shows that projected future developments in Power-to-Hydrogen technologies can greatly reduce the direct CO₂ abatement cost to 54 EUR/t CO₂-eq. An analysis of the total GHG emissions shows that decarbonization through Power-to-Hydrogen reduces the global GHG emissions only if the emission factor of the electricity supply lies below 160 g CO2-eq/kWhel.

The results suggest that decarbonization of copper production by Power-to-Hydrogen could become economically and environmentally beneficial over the next decades due to cheaper and more efficient Power-to-Hydrogen technology rising GHG emission certificate prices and further decarbonization of the electricity supply.

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 pinning effect to make the spins in paramagnetic oxyhydroxides more aligned for higher intrinsic OER activity. The spin pinning effect is established in oxideFM/oxyhydroxide interface which is realized by a controlled surface reconstruction of ferromagnetic oxides. Under spin pinning simple magnetization further increases the spin alignment and thus the OER activity which validates the spin effect in rate-limiting OER step. The spin polarization in OER highly relies on oxyl radicals (O∙) created by 1st dehydrogenation to reduce the barrier for subsequent O-O coupling.

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 problem that determines the optimal selection size and location of the hydrogen production technologies and the optimal structure of the hydrogen biomass and CO₂ O2 networks. First we investigate the rationale behind the optimal design of low-carbon hydrogen supply chains by referring to an idealized system configuration and by performing a parametric analysis of the most relevant design parameters of the supply chains such as biomass availability. This allows drawing general conclusions independent of any specific geographic features about the minimum-cost and minimum-emissions system designs and network structures. Moreover we analyze the Swiss case study to derive specific guidelines concerning the design of hydrogen supply chains deploying carbon capture and storage. We assess the impact of relevant design parameters such as location of CO₂ storage facilities techno-economic features of CO₂ capture technologies and network losses on the optimal supply chain design and on the competition between the hydrogen and CO₂ networks. Findings highlight the fundamental role of biomass (when available) and of carbon capture and storage for decarbonizing hydrogen supply chains while transitioning to a wider deployment of renewable energy sources.

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 recommendations. Insights are drawn from 1605 experimental investment-related decisions obtained from 42 high-level institutional investors and utility representatives. Results reveal that both investor groups view revenue stacking as key to making ESS investment viable. While the expected return on investment is the most important project characteristic risk-return preferences for other features diverge between groups. Institutional investors appear more open to exploring new technological ventures (20% of utility respondents would not consider making investments into solar photovoltaic-hydrogen) whereas utilities seem to prefer greenfield projects (23% of surveyed institutional investors rejected such projects). Interestingly both groups show strong aversion towards energy market price risk. Institutional investors require a premium of 6.87 percentage points and utilities 5.54 percentage points for moving from a position of fully hedged against market price risk to a scenario where only 20% of revenue is fixed underlining the need for policy support.

To maximise power density practical gas turbine combustion systems have several injectors which can lead to complex interactions between flames. However our knowledge about the effect of flame-flame interactions on the flame response the essential element to predict the stability of a combustor is still limited. The present study investigates the effect of hydrogen enrichment flame-flame interaction confinement and asymmetries on the linear and non-linear acoustic response of three premixed flames in a simple can combustor. A parametric study of the linear response characterised by the flame transfer function (FTF) is performed for swirling and non-swirling flames. Flame-flame interactions were achieved by changing the injector spacing and the level of hydrogen enrichment by power from 10 to 50%. It was found that the latter had the most significant effect on the flame response. Asymmetry effects were investigated by changing one of the flames by using a different bluff-body to alter both the flame shape and flow field. The global flame response showed that the asymmetric cases can be reconstructed using a superposition of the two symmetric cases where all three bluff-bodies and flames are the same. Overall the linear response characterised by the flame transfer function (FTF) showed that the effect of increasing the level of hydrogen enrichment is more pronounced than the effect of the injector spacing. Increasing hydrogen enrichment results in more compact flames which minimises flame-flame interactions. More compact flames increase the cut-off frequency which can lead to self-excited modes at higher frequencies. Finally the non-linear response was characterised by measuring the flame describing function (FDF) at a frequency close to a self-excited mode of the combustor for different injector spacings and levels of hydrogen enrichment. It is shown that increasing the hydrogen enrichment leads to higher saturation amplitude whereas the effect of injector spacing has a comparably smaller effect.

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 by means of a conventional spark discharge followed by a diffusion-controlled combustion while injection remains active. An optically accessible Rapid Compression Expansion Machine (RCEM) is used to investigate ignition and combustion of underexpanded hydrogen jets in air by means of simultaneous Schlieren visualization and OH chemiluminescence. Different injection and ignition timing are investigated resulting in premixed partially premixed and diffusion-controlled (jet-guided) combustion conditions. The possibility of ignition and combustion of the hydrogen jets in diffusion-controlled conditions is investigated for different orientations of the incoming fuel jet with respect to spark location. The combustion tests are analyzed in terms of ignition success rate ignition delay reacting surface and heat release rate and an optimal orientation of the jet is assessed. The present study provides insights for optimizing hydrogen direct injection ignition and combustion for later application in ICEs.

The need for a rapid transformation to low-carbon economies has rekindled hydrogen as a promising energy carrier. Yet the full range of environmental consequences of large-scale hydrogen production remains unclear. Here prospective life cycle analysis is used to compare different options to produce 500 Mt/yr of hydrogen including scenarios that consider likely changes to future supply chains. The resulting environmental and human health impacts of such production levels are further put into context with the Planetary Boundaries framework known human health burdens the impacts of the world economy and the externality-priced production costs that embody the environmental impact. The results indicate that climate change impacts of projected production levels are 3.3–5.4 times higher than the allocated planetary boundary with only green hydrogen from wind energy staying below the boundary. Human health impacts and other environmental impacts are less severe in comparison but metal depletion and ecotoxicity impacts of green hydrogen deserve further attention. Priced-in environmental damages increase the cost most strongly for blue hydrogen (from ∼2 to ∼5 USD/kg hydrogen) while such true costs drop most strongly for green hydrogen from solar photovoltaic (from ∼7 to ∼3 USD/kg hydrogen) when applying prospective life cycle analysis. This perspective helps to evaluate potentially unintended consequences and contributes to the debate about blue and green hydrogen.

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. By incorporating PBs into a mixed-integer linear programming model (MILP) we identify SC configurations that satisfy a given transport demand while minimising the PBs transgression level i.e. while reducing the risk of surpassing the ecological capacity of the Earth. On applying this methodology to the UK we find that the current fossil-based sector is unsustainable as it transgresses the energy imbalance CO2 concentration and ocean acidification PBs heavily i.e. five to 55-fold depending on the downscale principle. The move to hydrogen would help to reduce current transgression levels substantially i.e. reductions of 9–86% depending on the case. However it would be insufficient to operate entirely within all the PBs concurrently. The minimum impact SCs would produce hydrogen via water electrolysis powered by wind and nuclear energy and store it in compressed form followed by distribution via rail which would require as much as 37 TWh of electricity per year. Our work unfolds new avenues for the incorporation of PBs in the assessment and optimisation of energy systems to arrive at sustainable solutions that are entirely consistent with the carrying capacity of the planet.

Proton-exchange membrane fuel cells (PEMFCs) are regarded as promising alternatives to internal combustion engines (ICEs) to reduce pollution. Recent research on PEMFCs focuses on achieving higher power densities reducing the refueling time mitigating the final price and decreasing the degradations to facilitate the commercialization of hydrogen mobility. The design of bipolar plates and compression kits in addition to their coating can effectively improve performance increase durability and support water/thermal management. Past reviews usually focused on the specific aspect which can hardly provide readers with a complete picture of the key challenges facing and advances in the long-term performance of PEMFCs. This paper aims to deliver a comprehensive source to review from both experimental analytical and numerical viewpoints design challenges degradation modeling protective coatings for bipolar plates and key operational challenges facing and solutions to the stack to prevent contamination. The significant research gaps in the long-term performance of PEMFCs are identified as (1) improved bipolar-plate design and coating (2) the optimization of the design of sealing and compression kits to reduce mechanical stresses and (3) stack degradation regarding fuel contamination and dynamic operation.

Transitioning from carbon-intensive steam methane reforming to low-carbon hydrogen production is essential for decarbonizing the European industrial sector. However the employment impact of such a transition remains unclear. Here we estimate the effects using a transition pathways optimization model and industrial survey data. The results show that an electrolysis-based hydrogen sector transition would create 40000 jobs in the hydrogen sector by 2050. However these jobs are not equally distributed with Western Europe hosting the largest share (40%) and 20% of current hydrogen-producing regions experiencing net job decreases. Even after accounting for renewable energy jobs created by electrolysis-driven electricity demand growth the 2050 low-carbon hydrogen workforce would provide only 10% of the jobs currently offered by European fossil fuel production. Numerous uncertainties and regional development inequities suggest the need for sector-diversified workforce transition plans and training programs to foster skills suited to multiple low-carbon opportunities.

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 requirements with respect to mass flow measurement accuracy at these measurement conditions. As a result of the very dynamic filling process it was observed that the accuracy of mass flow measurement at different pressure ranges is not sufficient. At higher pressures it was found that particularly short refueling times cause significant measurement deviations. On this background it may be concluded that pressure has a great impact on the accuracy of mass flow measurement. To gain a deeper understanding of this matter RISE has built a unique high-pressure test facility. With the aid of this newly developed test rig it is possible to calibrate CFMs over a wide pressure and flow range with water or base oils as test medium. The test rig allows calibration measurements under the conditions prevailing at a 70 MPa HRS regarding mass flows (up to 3.6 kg min−1) and pressures (up to 87.5 MPa).