Applications & Pathways

This brochure offers an overview of the main applications of fuel cell and hydrogen technologies and how they work and provides insights into our programme and our accomplishments.

In Europe electrification is considered a key option to obtain a cleaner production of steel at the same time as the electricity system production portfolio is expected to consist of an increasing share of varying renewable electricity (VRE) generation mainly in the form of solar PV and wind power. We investigate cost-efficient designs of hydrogen-based steelmaking in electricity systems dominated by VRE. We develop and apply a linear cost-minimization model with an hourly time resolution which determines cost-optimal operation and sizing of the units in hydrogen-based steelmaking including an electrolyser direct reduction shaft electric arc furnace as well as storage for hydrogen and hot-briquetted iron pellets. We show that the electricity price following steelmaking leads to savings in running costs but to increased capital cost due to investments in the overcapacity of steel production units and storage units for hydrogen and hot-briquetted iron pellets. For two VRE-dominated regions we show that the electricity price following steel production reduces the total steel production cost by 23% and 17% respectively as compared to continuous steel production at a constant level. We also show that the cost-optimal design of the steelmaking process is dependent upon the electricity system mix.

The key project objectives include:

• Understand the range size type mode of operation and control system of installed gas engines in the UK. This will include equipment for CHP and for stand-by power operation.
• Produce data sets on the impact of hydrogen on gas engine operational performance.
• Develop knowledge on the impact of hydrogen content on the operation of the gas engine including overall efficiency changes to emissions profiles overall system operability.
• Providing outline guidance on a potential hydrogen limit that should be considered regarding use of natural gas/hydrogen mixed fuels in gas engines.
• Outlining a high-level view on the reliability and impact on maintenance and replacement regimes if gas engines operate on natural gas/hydrogen mixed fuels for extended time periods.
• Highlight any existing barriers to use of natural gas and hydrogen blends in gas engine and through contact with OEMs develop an understanding of future technology developments that may be needed to enable the use of “high” hydrogen blends.

The main aim is to characterise the impact of using natural gas/hydrogen fuel mixtures on the operation of gas engines used in CHP systems.

The output from this project will also inform the HyDeploy NIC project in relation to potential hydrogen content limits. The project will be presented at the IGEM Gas Quality Working Group (IGEM GQWG).

This report and any attachment is freely available on the ENA Smarter Networks Portal here. IGEM Members can download the report and any attachment directly by clicking on the pdf icon above.

Many railway vehicles use diesel as their energy source but exhaust emissions and concerns about economical fuel supply demand alternatives. Railway electrification is not cost effective for some routes particularly low-traffic density regional lines. The journey of a regional diesel–electric train is simulated over the British route Birmingham Moor Street to Stratford-upon-Avon and return to establish a benchmark for the conceptual design of a hydrogen-powered and hydrogen-hybrid vehicle. A fuel cell power plant compressed hydrogen at 350 and 700 bar and metal-hydride storage are evaluated. All equipment required for the propulsion can be accommodated within the space of the original diesel– electric train while not compromising passenger-carrying capacity if 700 bar hydrogen tanks are employed. The hydrogen trains are designed to meet the benchmark journey time of 94 min and the operating range of a day without refuelling. An energy consumption reduction of 34% with the hydrogen-powered vehicle and a decrease of 55% with the hydrogen-hybrid train are achieved compared with the original diesel–electric. The well-to-wheel carbon dioxide emissions are lower for the conceptual trains: 55% decrease for the hydrogen-powered and 72% reduction for the hydrogen-hybrid assuming that the hydrogen is produced from natural gas.

This paper revisits the theoretical concepts of lock-in mechanisms to analyse transition processes in energy production and road transportation in the Nordic countries focussing on three technology platforms: advanced biofuels e-mobility and hydrogen and fuel cell electrical vehicles. The paper is based on a comparative analysis of case studies.<br/>The main lock-in mechanisms analysed are learning effects economies of scale economies of scope network externalities informational increasing returns technological interrelatedness collective action institutional learning effects and the differentiation of power.<br/>We show that very different path dependencies have been reinforced by the lock-in mechanisms. Hence the characteristics of existing regimes set the preconditions for the development of new transition pathways. The incumbent socio-technical regime is not just fossil-based but may also include mature niches specialised in the exploitation of renewable sources. This implies a need to distinguish between lock-in mechanisms favouring the old fossil-based regime well-established (mature) renewable energy niches or new pathways.

Today electricity & heat generation transportation and industrial sectors together produce more than 80% of energy-related CO₂ emissions. Hydrogen may be used as an energy carrier and an alternative fuel in the industrial residential and transportation sectors for either heating energy production from fuel cells or direct fueling of vehicles. In particular the use of hydrogen fuel cell vehicles (HFCVs) has the potential to virtually eliminate CO₂ emissions from tailpipes and considerably reduce overall emissions from the transportation sector. Although steam methane reforming (SMR) is the dominant industrial process for hydrogen production environmental concerns associated with CO₂ emissions along with the process intensification and energy optimization are areas that still require improvement. Metallic membrane reactors (MRs) have the potential to address both challenges. MRs operate at significantly lower pressures and temperatures compared with the conventional reactors. Hence the capital and operating expenses could be considerably lower compared with the conventional reactors. Moreover metallic membranes specifically Pd and its alloys inherently allow for only hydrogen permeation making it possible to produce a stream of up to 99.999+% purity.

For smaller and emerging hydrogen markets such as the semiconductor and fuel cell industries Pd-based membranes may be an appropriate technology based on the scales and purity requirements. In particular at lower hydrogen production rates in small-scale plants MRs with CCUS could be competitive compared to centralized H₂ production. On-site hydrogen production would also provide a self-sufficient supply and further circumvent delivery delays as well as issues with storage safety. In addition hydrogen-producing MRs are a potential avenue to alleviate carbon emissions. However material availability Pd cost and scale-up potential on the order of 1.5 million m3/day may be limiting factors preventing wider application of Pd-based membranes.

Regarding the economic production of hydrogen the benchmark by the year 2020 has been determined and set in place by the U.S. DOE at less than $2.00 per kg of produced hydrogen. While the established SMR process can easily meet the set limit by DOE other carbon-free processes such as water electrolysis electron beam radiolysis and gliding arc technologies do not presently meet this requirement. In particular it is expected that the cost of hydrogen produced from natural gas without CCUS will remain the lowest among all of the technologies while the hydrogen cost produced from an SMR plant with solvent-based carbon capture could be twice as expensive as the conventional SMR without carbon capture. Pd-based MRs have the potential to produce hydrogen at competitive prices with SMR plants equipped with carbon capture.

Despite the significant improvements in the electrolysis technologies the cost of hydrogen produced by electrolysis may remain significantly higher in most geographical locations compared with the hydrogen produced from fossil fuels. The cost of hydrogen via electrolysis may vary up to a factor of ten depending on the location and the electricity source. Nevertheless due to its modular nature the electrolysis process will likely play a significant role in the hydrogen economy when implemented in suitable geographical locations and powered by renewable electricity.

This review provides a critical overview of the opportunities and challenges associated with the use of the MRs to produce high-purity hydrogen with low carbon emissions. Moreover a technoeconomic review of the potential methods for hydrogen production is provided and the drawbacks and advantages of each method are presented and discussed.

In Norway where nearly 100% of the power is hydroelectric it is natural to consider water electrolysis as the main production method of hydrogen for zero-emission transport. In a start-up market with low demand for hydrogen one may find that small-scale WE-based hydrogen production is more cost-efficient than large-scale production because of the potential to reach a high number of operating hours at rated capacity and high overall system utilization rate. Two case studies addressing the levelized costs of hydrogen in local supply systems have been evaluated in the present work: (1) Hydrogen production at a small-scale hydroelectric power plant (with and without on-site refuelling) and (2) Small hydrogen refuelling station for trucks (with and without on-site hydrogen production). The techno-economic calculations of the two case studies show that the levelized hydrogen refuelling cost at the small-scale hydroelectric power plant (with a local station) will be 141 NOK/kg while a fleet of 5 fuel cell trucks will be able to refuel hydrogen at a cost of 58 NOK/kg at a station with on-site production or 71 NOK/kg at a station based on delivered hydrogen. The study shows that there is a relatively good business case for local water electrolysis and supply of hydrogen to captive fleets of trucks in Norway particularly if the size of the fleet is sufficiently large to justify the installation of a relatively large water electrolyzer system (economies of scale). The ideal concept would be a large fleet of heavy-duty vehicles (with a high total hydrogen demand) and a refuelling station with nearly 100% utilization of the installed hydrogen production capacity.

The 30 integrated steel plants operating in the European Union (EU) are among the largest single-point CO₂ emitters in the region. The deployment of bioenergy with carbon capture and storage (bio-CCS) could significantly reduce their emission intensities. In detail the results demonstrate that CO₂ emission reduction targets of up to 20% can be met entirely by biomass deployment. A slow CCS technology introduction on top of biomass deployment is expected as the requirement for emission reduction increases further. Bio-CCS could then be a key technology particularly in terms of meeting targets above 50% with CO₂ avoidance costs ranging between €60 and €100 tCO2−1 at full-scale deployment. The future of bio-CCS and its utilisation on a larger scale would therefore only be viable if such CO₂ avoidance cost were to become economically appealing. Small and medium plants in particular would economically benefit from sharing CO₂ pipeline networks. CO₂ transport however makes a relatively small contribution to the total CO₂ avoidance cost. In the future the role of bio-CCS in the European iron and steelmaking industry will also be influenced by non-economic conditions such as regulations public acceptance realistic CO₂ storage capacity and the progress of other mitigation technologies.

The work is dedicated to the possibility of using hydrogen-powered vehicles in urban transport systems. Due to the need to look for alternative solutions for vehicles with conventional drive in cities hydrogen-powered cars are one of the practical possibilities of realizing the sustainable transport assumptions and independence from oil imports - which is one of the main priorities of the European Union. This paper presents a literature analysis the analysis of the current state and development of use hydrogen-powered vehicles in the world.<br/>The article refers to the possibilities of use hydrogen-vehicles in different ways of mobility: individual vehicles taxis and shared mobility. In addition the author focused on showing the advantages and disadvantages of using hydrogen-powered vehicles in urban transport systems.

In 2016 for the first time a polymer electrolyte fuel cell free of Pt electrocatalysts was shown to deliver more than 0.5 W cm-2 of peak power density from H2 and air (CO2 free). This was achieved with a silver-based oxygen reduction (ORR) cathode and a Pd-CeO2 hydrogen oxidation reaction (HOR) anodic electrocatalyst. The poor kinetics of the HOR under alkaline conditions is a considerable challenge to Anion Exchange Membrane Fuel Cell (AEMFC) development as high Pt loadings are still required to achieve reasonable performance. Previously the ameliorative combination of Pd and CeO2 nanocomposites has been exploited mostly in heterogeneous catalysis where the positive interaction is well documented. Carbon supported PdCeO2 HOR catalysts have now been prepared by different synthetic techniques and employed in AEMFCs as alternative to Pt and PtRu standards. Important research has also been recently reported delving into the origin of the HOR enhancement on Pd-CeO2. Such work has highlighted the importance of the bifunctional mechanism of the HOR at high pHs. Carefully prepared nano-structures of Pd and CeO2 that promote the formation of the Pd-O-Ce interface provide optimal binding of both Had and OHad species aspects which are crucial for enhanced HOR kinetics. This review paper discusses the recent advances in Pd-CeO2 electrocatalysts for AEMFC anodes.

Biomass derived porous nanostructured nitrogen doped carbon (PNC) has been extensively investigated as the electrode material for electrochemical catalytic reactions and rechargeable batteries. Biomass with and without containing nitrogen could be designed and optimized to prepare PNC via hydrothermal carbonization pyrolysis and other methods. The presence of nitrogen in carbon can provide more active sites for ion absorption improve the electronic conductivity increase the bonding between carbon and sulfur and enhance the electrochemical catalytic reaction. The synthetic methods of natural biomass derived PNC heteroatomic co- or tri-doping into biomass derived carbon and the application of biomass derived PNC in rechargeable Li/Na batteries high energy density Li–S batteries supercapacitors metal-air batteries and electrochemical catalytic reaction (oxygen reduction and evolution reactions hydrogen evolution reaction) are summarized and discussed in this review. Biomass derived PNCs deliver high performance electrochemical storage properties for rechargeable batteries/supercapacitors and superior electrochemical catalytic performance toward hydrogen evolution oxygen reduction and evolution as promising electrodes for electrochemical devices including battery technologies fuel cell and electrolyzer.

Hydrogen evolution reaction (HER) plays a key role in generating clean and renewable energy. As the most effective HER electrocatalysts Pt group catalysts suffer from severe problems such as high price and scarcity. It is highly desirable to design and synthesize sustainable HER electrocatalysts to replace the Pt group catalysts. Due to their low cost high abundance and high activities cobalt-incorporated N-doped nanocarbon hybrids are promising candidate electrocatalysts for HER. In this report we demonstrated a robust and eco-friendly host-guest approach to fabricate metallic cobalt nanoparticles embedded in N-doped carbon fibers derived from natural silk fibers. Benefiting from the one-dimensional nanostructure the well-dispersed metallic cobalt nanoparticles and the N-doped thin graphitized carbon layer coating the best Co-based electrocatalyst manifests low overpotential (61 mV@10 mA/cm2) HER activity that is comparable with commercial 20% Pt/C and good stability in acid. Our findings provide a novel and unique route to explore high-performance noble-metal-free HER electrocatalysts.

Hydrogen is widely recognised as an important option for future road transportation but a widespread infrastructure must be developed if the potential for hydrogen is to be achieved. This paper and related appendices which can be downloaded as Supplementary material present a mixed-integer linear programming model (called SHIPMod) that optimises a hydrogen supply chains for scenarios of hydrogen fuel demand in the UK including the spatial arrangement of carbon capture and storage infrastructure. In addition to presenting a number of improvements on past practice in the literature the paper focuses attention on the importance of assumptions regarding hydrogen demand. The paper draws on socio-economic data to develop a spatially detailed scenario of possible hydrogen demand. The paper then shows that assumptions about the level and spatial dispersion of hydrogen demand have a significant impact on costs and on the choice of hydrogen production technologies and distribution mechanisms.

Presently the fulfilment of world’s energy demand highly relies on the fossil fuel i.e. coal oil and natural gas. Fossil fuels pose threat to environment and biological systems on the earth. Usage of these fuels leads to an increase in the CO2 content in the atmosphere that causes global warming and undesirable climatic changes. Additionally these are limited sources of energy those will eventually dwindle. There is huge urge of identifying and utilizing the renewable energy resources to replace these fossil fuels in the near future as it is expected to have no impact on environment and thus would enable one to provide energy security. Hydrogen is one of the most desirable fuel capable of replacing vanishing hydrocarbons. In this review we present the status of energy demands recent advances in renewable energy and the prospects of hydrogen as a future fuel are highlighted. It gives a broad overview of different energy systems and mainly focuses on different technologies and their reliability for the production of hydrogen in present and future.

This paper presents techno-economic modelling results of a nationwide hydrogen fuel supply chain (HFSC) that includes renewable hydrogen production transportation and dispensing systems for fuel cell electric buses (FCEBs) in Ireland. Hydrogen is generated by electrolysers located at each existing Irish wind farm using curtailed or available wind electricity. Additional electricity is supplied by on-site photovoltaic (PV) arrays and stored using lithium-ion batteries. At each wind farm sizing of the electrolyser PV array and battery is optimised system design to obtain the minimum levelised cost of hydrogen (LCOH). Results show the average electrolyser capacity factor is 64% after the integration of wind farm-based electrolysers with PV arrays and batteries. A location-allocation algorithm in a geographic information system (GIS) environment optimises the distributed hydrogen supply chain from each wind farm to a hypothetical hydrogen refuelling station in the nearest city. Results show that hydrogen produced transported and dispensed using this system can meet the entire current bus fuel demand for all the studied cities at a potential LCOH of 5–10 €/kg by using available wind electricity. At this LCOH the future operational cost of FCEBs in Belfast Cork and Dublin can be competitive with public buses fuelled by diesel especially under carbon taxes more reflective of the environmental impact of fossil fuels.

Fuel Cell Vehicles (FCVs) are a disruptive innovation and are currently looking towards niche market entry. However commercialisation has been unsuccessful thus far and there is a limited amount of literature that can guide their market entry. In this paper a historical case study is undertaken which looks at Tesla Motors high-end encroachment market entry strategy. FCVs have been compared to Tesla vehicles due to their similarities; both are disruptive innovations both are high cost and both are zero emission vehicles. Therefore this paper looks at what can be learned form Tesla Motors successful market entry strategy and proposes a market entry strategy for FCVs. It was found that FCVs need to enact a paradigm shift from their current market entry strategy to one of high-end encroachment. When this has been achieved FCVs will have greater potential for market penetration.

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 electric vehicles biofuels natural gas liquefied petroleum gas etc. However there is a lack of comprehensive information on the techno-economic performance of production pathways for alternative fuels. The acquisition of robust techno-economic data is still a challenge for energy planners modellers analysts and policy-makers when building their prospective models to support decision-making processes. Hence this article aims to fill this gap through a deep literature review including the most representative production routes for a wide range of road transportation fuels. This led to the development of datasets including investment costs operating and maintenance costs and transformation efficiencies for more than 40 production pathways. The techno-economic data presented in this work are expected to be especially useful to those energy actors interested in performing long-term studies on the transition to a sustainable transport system.

In this paper the effect of direct diesel injection timing and engine speed on the performance and emissions of CI engine operating on RCCI (H2/diesel mixture) coupled with water injection have been numerically investigated and validated. The simulation have been carried out using GT-Power professional software. A single cylinder dual fuel compression ignition model has been built. The diesel fuel was injected directly to the cylinder. The hydrogen and water were injected to the engine intake manifold and engine port with constant mass flow rate and constant temperature for all engine speed. During the simulation the engine speed was varied from 1000 to 5000 rpm and the diesel injection timing was varied from (−5° to −25° CAD). In addition the optimized diesel injection timing for specific engine operation parameters has also been performed. The results show that for specific injection timing and constant hydrogen and water mass flow rate the increase of engine speed results in an increase in the cylinder temperature engine brake power brake specific fuel consumption and NO emissions; but decreases brake thermal efficiency. Moreover the analysis performed shows that the advanced injection timing decreases the engine power brake thermal efficiency and CO emissions; but increases NO emissions.

The influence of the previous electrolytic hydrogenation on the micromechanical properties and tribological behavior of the surface layers of iron and carbon steels has been studied. The concentrations of diffusion-moving and residual hydrogen in steels are determined depending on the carbon content. It is shown that the amount of sorbed hydrogen is determined by the density of dislocations and the relative volume of cementite. After desorption of diffusion-moving hydrogen the microhardness increases and materials plasticity decreases. The change of these characteristics decreases with the increase of carbon content in the steels. Internal stresses increase and redistribute under hydrogen desorption. Fragmentation of ferrite and perlite occurs as a result of electrolytic hydrogenation. Ferrite is characterized by the structure fragmentation and change of the crystallographic orientation of planes. The perlite structure shows the crushing of cementite plates and their destruction. The influence of hydrogen desorption on the microhardness of structural components of ferrite-perlite steels is shown. Large scattering of microhardness is found in perlite due to different diffusion rates of hydrogen because of the unequally oriented cementite plates. It was found that the tendency of materials to blister formation is reduced with the increase of carbon content. The influence of hydrogen on the tribological behaviour of steels under dry and boundary friction has been studied. It is shown that hydrogen desorption intensifies the materials wear. After hydrogen desorption tribological behaviour is determined by the adhesion interaction between the contacting pairs.

As a developing country the Philippines must balance its rapid industrialization efforts with the realities and consequences of climate change on the country. A feasible option to achieve this is increasing the share of renewables in power generation coupled with energy storage technology. This paper examines the present situation and opportunities for development of hydrogen and fuel cell technology in the Philippines as promising alternatives with proven applications in niche energy demand sectors aside from renewables integration. Although the Philippines is considered a latecomer there is significant renewable resource potential available local experts and trained talents and enabling legislations in the country that provide opportunities in harnessing fuel cell technologies for the transition to energy self-sufficient and low-carbon society. Current advancement of the technology in the country is limited to an initial 5-year roadmap focused on component development from cheap and local materials. Provisions for large-scale hydrogen infrastructure have not yet been realized which is comparable to the early stages of development in other countries that are also pursuing fuel cell technology. Strong industry-academe partnerships should be pursued through a specific legislated agency to ensure future development of this technology for the country’s benefit. Lastly applications in distributed power generation poised to be a lucrative direction as demonstration and validation with other potential uses such as transportation remains a challenge.

This article presents a power to SNG (synthetic natural gas) system that converts hydrogen into SNG via a methanation process. In our analysis detailed models for all the elements of the system are built. We assume a direct connection between a wind farm and a hydrogen generator. For the purposes of our calculations we also assume that the hydrogen generator is powered by the renewable source over a nine-hour period per day (between 21:00 and 06:00) and this corresponds to the off-peak period in energy demand. In addition a hydrogen tank was introduced to maximize the operating time of the methanation reactor. The cooperation between the main components of the system were simulated using Matlab software. The primary aim of this paper is to assess the influence of various parameters on the operation of the proposed system and to optimize its yearly operation via a consideration of the most important constraints. The analyses also examine different nominal power values of renewables from 8 to 12 MW and hydrogen generators from 3 to 6 MW. Implementing the proposed configuration taking into account the direct connection of the hydrogen generator and the methanation reactor showed that it had a positive effect on the dynamics and the operating times of the individual subsystems within the tested configuration

Energy transition is a part of a much wider Grand Transition which is not all about energy. Energy transition cannot be achieved all at once or by any one actor. Relying only on better energy modelling and forecasting to guide successful transition will be fatal even in a data-rich era.<br/>It is timely for energy leaders to ask:<br/>Are global energy scenarios achieving their potential in opening up action on new energy futures?<br/>How do the Council’s World Energy Scenarios compare with global energy outlooks scenarios and normative visions used by others and what can we learn by contrasting the increasing richness of energy futures thinking?<br/>In anticipation of the 24th World Energy Congress the Council is refreshing its global energy foresight and updating its global scenarios narratives. The focus is on an ‘innovation twist to 2040’ and the use of scenarios to explore and navigate new exponential growth opportunities for accelerating successful energy transition in an era of epic and disruptive innovation.<br/>As a part of the refresh the Council has conducted a comparison study of global energy scenarios in order to test the continued plausibility relevance and challenge of its own existing scenario set the World Energy Scenarios 2016 launched at the 23rd World Energy Congress in Istanbul in 2016.<br/>By comparing the methods narratives and assumptions associated with a benchmarkable set of global energy futures initiatives and studies the Council seeks to provide our members with clearer understanding and new insights on energy transition while preparing them to better engage with leadership dialogues which pivot on visions of a new energy future.<br/>The review also provides an opportunity to reflect on the challenges and obstacles for utilising global energy scenarios to drive impact and the challenges in bridging agile and flexible qualitative storytelling with long term quantitative energy modelling."

In the past material innovation has changed society through new material-induced technologies adding a new value to society. In the present world engineers and scientists are expected to invent new materials to solve the global problem of climate change. For the transport sector the challenge for material engineers is to change the oil-based world into a sustainable world. After witnessing the recent high oil price and its adverse impact on the global economy it is time to accelerate our efforts towards this change.

Industries are tackling global energy issues such as oil and CO₂ as well as local environmental problems such as NOx and particulate matter. Hydrogen is the most promising candidate to provide carbon-free emission-free and oil-free mobility. As such engineers are working very hard to bring this technology into the real society. This paper describes recent progress of vehicle technologies as well as hydrogen-storage technologies to extend the cruise range and ensure the easiness of refuelling and requesting material scientists to collaborate with industry to fight against global warming.

Link to document download on Royal Society Website  

A new route for making steel from iron ore based on the use of hydrogen to reduce iron oxides is presented detailed and analyzed. The main advantage of this steelmaking route is the dramatic reduction (90% off) in CO2 emissions compared to those of the current standard blast-furnace route. The first process of the route is the production of hydrogen by water electrolysis using CO2-lean electricity. The challenge is to achieve massive production of H2 in acceptable economic conditions. The second process is the direct reduction of iron ore in a shaft furnace operated with hydrogen only. The third process is the melting of the carbon-free direct reduced iron in an electric arc furnace to produce steel. From mathematical modeling of the direct reduction furnace we show that complete metallization can be achieved in a reactor smaller than the current shaft furnaces that use syngas made from natural gas. The reduction processes at the scale of the ore pellets are described and modeled using a specific structural kinetic pellet model. Finally the differences between the reduction by hydrogen and by carbon monoxide are discussed from the grain scale to the reactor scale. Regarding the kinetics reduction with hydrogen is definitely faster. Several research and development and innovation projects have very recently been launched that should confirm the viability and performance of this breakthrough and environmentally friendly ironmaking process.

Hydrogen is expected to become a key component in the decarbonized energy systems of the future. Its unique chemical characteristics make hydrogen a carbon-free fuel that is suitable to be used as broadly as fossil fuels are used today. Since hydrogen can be produced by splitting water molecules using electricity as the only energy input needed hydrogen offers the opportunity to produce a fully renewable fuel if the electricity input also only stems from renewable sources. Once renewable electricity is converted into hydrogen it can be stored over long periods of time and transported over long even intercontinental distances. Underground hydrogen storage pipelines compressors liquefaction-units and transportation ships are infrastructures and suitable technologies to establish a global hydrogen energy system. Several chemical synthesis routes exist to produce more complex products from green hydrogen to fulfil the demands of various end-users and industries. One exemplary power-to-gas product is methane which can be used as a natural gas substitute. Furthermore ammonia alcohols kerosene and all other important products from hydrocarbon chemistry can be synthesized using green hydrogen.