Publications

Decarbonising ammonia production is an environmental imperative given that it independently accounts for 1.8% of global carbon dioxide emissions and supports the feeding of over 48% of the global population. The recent decline of production costs and its potential as an energy vector warrant investigation of whether green ammonia production is commercially competitive. Considering 534 locations in 70 countries and designing and operating the islanded production process to minimise the levelised cost of ammonia (LCOA) at each we show the range of achievable LCOA the cost of process flexibility the components of LCOA and therein the scope of LCOA reduction achievable at present and in 2030. These results are benchmarked against ammonia spot prices cost per GJ of refined fuels and the LCOE of alternative energy storage methods. Currently a LCOA of $473 t1 is achievable at the best locations the required process flexibility increases the achievable LCOA by 56%; the electrolyser CAPEX and operation are the most significant costs. By 2030 $310 t1 is predicted to be achievable with multiple locations below $350 t1 . At $25.4 GJ11 ) that do not have the benefit of being carbon-free.

Hydrogen fuel cell vehicle industry is in a rapid development stage. Studying the domestic spatial distribution of hydrogen fuel cell vehicle industry across a country especially the spatio-temporal evolution of the innovation level and position of each region in innovation network will help to understand the industry’s development trends and characteristics and avoid repeated construction. This article uses social network analysis and patent citation information of 2971 hydrogen fuel cell vehicle related invention patents owned by 218 micro-innovators across 25 provinces of China from 2001 to 2020 to construct China’s hydrogen fuel cell vehicle innovation network. Based on the dimensions of knowledge production knowledge consumption and network broker the network positions of sample provinces in three periods divided by four main national policies are classified. The main findings are as follows. 1) In China the total sales of hydrogen fuel cell vehicle and the development of supporting infrastructure are balanced and a series of national and local industrial development polices have been issued. 2) China’s hydrogen fuel cell vehicle innovation network density the proportion of universities and research institutes among the innovators and the active degree of the eastern provinces are all becoming higher. 3) The provinces in optimal network position are all from the eastern region. Shanghai and Liaoning are gradually replaced by Beijing and Jiangsu. 4) Sichuan in the western region is the only network broker based on knowledge consumption. 5) Although Zhejiang Tianjin Hebei Guangdong and Hubei are not yet in the optimal position they are outstanding knowledge producers. Specifically Guangdong is likely to climb to the optimal network position in the next period. The conclusions will help China’s provinces to formulate relevant development policies to optimize industry layout and enhance collaborative innovation in the hydrogen fuel cell vehicle industry.

Alongside the rapid expansion of wind power installation in China wind curtailment is also mounting rapidly due to China’s energy endowment imbalance. The hydrogen-based wind-energy storage system becomes an alternative to solve the puzzle of wind power surplus. This article introduced China’s energy storage industry development and summarized the advantages of hydrogen-based wind-energy storage systems. From the perspective of resource conservation it estimated the environmental benefits of hydrogen-based wind-energy storages. This research also builds a valuation model based on the Real Options Theory to capture the distinctive flexible charging and discharging features of the hydrogen-based wind-energy storage systems. Based on the model simulation results including the investment value and operation decision of the hydrogen energy storage system with different electricity prices system parameters and different levels of subsidies are presented. The results show that the hydrogen storage system fed with the surplus wind power can annually save approximately 2.19–3.29 million tons of standard coal consumption. It will reduce 3.31–4.97 million tons of CO2 SO2 NOx and PM saving as much as 286.6–429.8 million yuan of environmental cost annually on average. The hydrogen-based wind-energy storage system’s value depends on the construction investment and operating costs and is also affected by the meanreverting nature and jumps or spikes in electricity prices. The market-oriented reform of China’s power sector is conducive to improve hydrogen-based wind-energy storage systems’ profitability. At present subsidies are still essential to reduce initial investment and attract enterprises to participate in hydrogen energy storage projects.

With the high-proportion accession of renewable energy and randomness of the load side in the new energy power system unbalanced feeder power and heavy overload of the transformer caused by massive access of highly uncertain source loads become more and more serious. In order to solve the aforementioned problems a honeycomb topology of the multi-station integrated system is proposed. The soft open point (SOP) is used as the key integrated equipment of the internal unit of a multi-station integrated system. The honeycomb grid structure is composed of flexible nodes and the multi-station integrated system is composed of multi-network flexible interconnection. Based on the characteristics of the regional resource endowment hydrogen energy flow is deeply coupled in parts of honeycomb grids. In order to improve the reliability and flexibility of the multi-station integrated unit the structure of the new multi-station integrated unit the power balance constraints on the unit and the switching process of SOP control mode are studied. At the same time the hydrogen electricity coupling structure and the coordinated control strategy of hydrogen electricity conversion are proposed to solve the problem of deep application of hydrogen energy. Finally the effectiveness of the proposed multi-station integrated system is verified by using three simulation models.

Hydrogen is a low or zero-carbon energy source that is considered the most promising and potential energy carrier of the future. In this study the energy sources feedstocks and various methods of hydrogen production from power generation are comparatively investigated in detail. In addition this study presents an economic assessment to evaluate cost-effectiveness based on different economic indicators including sensitivity analysis and uncertainty analysis. Proton exchange membrane fuel cell (PEMFCs) technology has the most potential to be developed compared to several other technologies. PEMFCs have been widely used in various fields and have advantages (i.e. start-up zero-emissions high power density). Among the various sources of uncertainty in the sensitivity analysis the cost estimation method shows inflationary deviations from the proposed cost of capital. This is due to the selection process and untested technology. In addition the cost of electricity and raw materials as the main factors that are unpredictable.

Electrochemical ammonia generation allows direct low pressure synthesis of ammonia as an alternative to the established Haber-Bosch process. The increasing need to drive industry with renewable electricity central to decarbonisation and electrochemical ammonia synthesis offers a possible efficient and low emission route for this increasingly important chemical. It also provides a potential route for more distributed and small-scale ammonia synthesis with a reduced production footprint. Electrochemical ammonia synthesis is still early stage but has seen recent acceleration in fundamental understanding. In this work two different ammonia electrolysis systems are considered. Balance of plant (BOP) requirements are presented and modelled to compare performance and determine trade-offs. The first option (water fed cell) uses direct ammonia synthesis from water and air. The second (hydrogen-fed cell) involves a two-step electrolysis approach firstly producing hydrogen followed by electrochemical ammonia generation. Results indicate that the water fed approach shows the most promise in achieving low energy demand for direct electrochemical ammonia generation. Breaking the reaction into two steps for the hydrogen fed approach introduces a source of inefficiency which is not overcome by reduced BOP energy demands and will only be an attractive pathway for reactors which promise both high efficiency and increased ammonia formation rate compared to water fed cells. The most optimised scenario investigated here with 90% faradaic efficiency (FE) and 1.5 V cell potential (75% nitrogen utilisation) gives a power to ammonia value of 15 kWh/kg NH3 for a water fed cell. For the best hydrogen fed arrangement the requirement is 19 kWh/kg NH3. This is achieved with 0.5 V cell potential and 75% utilisation of both hydrogen and nitrogen (90% FE). Modelling demonstrated that balance of plant requirements for electrochemical ammonia are significant. Electrochemical energy inputs dominate energy requirements at low FE however in cases of high FE the BOP accounts for approximately 50% of the total energy demand mostly from ammonia separation requirements. In the hydrogen fed cell arrangement it was also demonstrated that recycle of unconverted hydrogen is essential for efficient operation even in the case where this increases BOP energy inputs

The establishment of near-autonomous micro-grids in commercial or public building complexes is gaining increasing popularity. Short-term storage capacity is provided by means of large battery installations or more often by the employees’ increasing use of electric vehicle batteries which are allowed to operate in bi-directional charging mode. In addition to the above short-term storage means a long-term storage medium is considered essential to the optimal operation of the building’s micro-grid. The most promising long-term energy storage carrier is hydrogen which is produced by standard electrolyzer units by exploiting the surplus electricity produced by photovoltaic installation due to the seasonal or weekly variation in a building’s electricity consumption. To this end a novel concept is studied in this paper. The details of the proposed concept are described in the context of a nearly Zero Energy Building (nZEB) and the associated micro-grid. The hydrogen produced is stored in a high-pressure tank to be used occasionally as fuel in an advanced technology hydrogen spark ignition engine which moves a synchronous generator. A size optimization study is carried out to determine the genset’s rating the electrolyzer units’ capacity and the tilt angle of the rooftop’s photovoltaic panels which minimize the building’s interaction with the external grid. The hydrogen-fueled genset engine is optimally sized to 40 kW (0.18 kW/kWp PV). The optimal tilt angle of the rooftop PV panels is 39◦ . The maximum capacity of the electrolyzer units is optimized to 72 kW (0.33 kWmax/kWp PV). The resulting system is tacitly assumed to integrate to an external hydrogen network to make up for the expected mismatches between hydrogen production and consumption. The significance of technology in addressing the current challenges in the field of energy storage and micro-grid optimization is discussed with an emphasis on its potential benefits. Moreover areas for further research are highlighted aiming to further advance sustainable energy solutions.

Hydrogen (H2) produced using renewable energy could be used to reduce greenhouse gas (GHG) emissions in industrial sectors such as steel chemicals transportation and energy storage. Knowing the delivered cost of renewable H2 is essential to decisionmakers looking to utilize it. The cheapest location to source it from as well as the transport method and medium are also crucial information. This study presents a Monte Carlo simulation to determine the delivered cost for renewable H2 for any usage location globally as well as the most cost-effective production location and transport route from nearly 6000 global locations. Several industrially dense locations are selected for case studies the primary two being Cologne Germany and Houston United States. The minimum delivered H2 cost to Cologne is 9.4 €/kg for small scale (no pipelines considered) shipped from northern Egypt as a liquid organic hydrogen carrier (LOHC) and 7.6 €/kg piped directly as H2 gas from southern France for large scale (pipelines considered). For smallscale H2 in Houston the minimum delivered cost is 8.6 €/kg trucked as H2 gas from the western Gulf of Mexico and 7.6 €/kg for large-scale demand piped as H2 gas from southern California. The south-west United States and Mexico northern Chile the Middle East and north Africa south-west Africa and north-west Australia are identified as the regions with the lowest renewable H2 cost potential with production costs ranging from 6.7—7.8 €/kg in these regions. Each is able to supply differing industrially dominant areas. Furthermore the effect of parameters such as year of construction electrolyser and H2 demand is analysed. For the case studies in Houston and Cologne the delivered H2 cost is expected to reduce to about 7.8 €/kg by 2050 in Cologne (no pipelines considered PEM electrolyser) and 6.8 €/kg in Houston.

Hydrogen (H2) is expected to be a key instrument to meet the European Union (EU) Green Deal main objective: i.e. climate neutrality by 2050. Renewable hydrogen deployment is expected to significantly reduce EU greenhouse gas (GHG) emissions by displacing carbon-intensive sources of energy. However concerns have been raised recently regarding the potential global warming impact caused by hydrogen emissions. Although hydrogen is neither intentionally emitted to the atmosphere when used nor a direct greenhouse gas hydrogen losses affect atmospheric chemistry indirectly contributing to global warming. To better understand the potential environmental impact of a hydrogen economy and to assess the need for action in this respect the Clean Hydrogen Joint Undertaking and the U.S. Department of Energy jointly organised with the support of the European Commission Hydrogen Europe Hydrogen Europe Research the Hydrogen Council and the International Partnership for Hydrogen and Fuel Cells in the Economy a 2-day expert workshop. Experts agreed that a low-carbon and in particular a renewable hydrogen economy would significantly reduce the global warming impact compared to a fossil fuel economy. However hydrogen losses to the atmosphere will impact the lifetime of other greenhouse gases namely methane ozone and water vapour indirectly contributing to the increase of the Earth’s temperature in the near-term. To minimise the climate impact of a hydrogen economy losses should therefore be minimised prevented and monitored. Unfortunately current loss rates along the hydrogen supply chain are not well constrained and are currently estimated to go from few percents for compressed hydrogen (1-4%) up to 10-20% for liquefied hydrogen. Both the global warming impact of hydrogen emissions and the leakage rates from a developed hydrogen economy are subject to a high level of uncertainty. It is therefore of paramount importance to invest in developing the ability to accurately quantify hydrogen emissions as well as engage in more research on hydrogen leakage prevention and monitoring systems. More data from the hydrogen industry and improved observational capacity are needed to improve the accuracy of the global hydrogen budget. Finally it is recommended to always report the amount and location of hydrogen emissions when environmental assessments are performed. There is a range of emission metrics and time scales that are designed to evaluate the climate impacts of short-lived GHG emissions compared to CO2 (i.e. CO2 equivalents). The metric choice must depend on the specific policy goal as they can provide very different perspectives on the relative importance of H2 emissions on the climate depending on the time horizon of concern. These differences need to be viewed in the context of the specific policy objectives.

This study deals with the use of hydrogen for the de-carbonization of the Resources and Energy Intensive Industries (REIIs) and gives a specific insight of the situation of the steel-making industry. The growing use of hydrogen in our economy is synonym for an equal increase in electricity consumption. This results from the fact that the current most promising technologies of H2 production is water electrolysis. For this purpose the EU hydrogen strategy foresees a progressive ramp up of H2 production capacities. But bottlenecks (especially regarding energy needed for electrolysers) may occur. Capacities should reach 40 GW (around 10 Mt/y) by the end of 2030. The steel-making industry relies heavily on H2 to decarbonise its process (through direct iron ore reduction). Our study analyses the conditions under which this new process will be able to compete with both European and offshore existing carbonised assets (i.e. blast furnaces). It emphasises the need for integrated and consistent policies from carbon prices to the carbon border adjustment mechanism through carbon contracts for differences but also highlightsthat a better regulation of electricity prices should not be neglected.

Green ammonia production as an important application for propelling the upcoming hydrogen economy has not been paid much attention by China the world's largest ammonia producer. As a result related studies are limited. This paper explores potential supply chain design and planning strategies of green ammonia production in the next decade of China with a case study in Inner Mongolia. A hybrid optimization-based simulation approach is applied considering traditional optimization approaches are insufficient to address uncertainties and dynamics in a long-term energy transition. Results show that the production cost of green ammonia will be at least twice that of the current level due to higher costs of hydrogen supply. Production accounts for the largest share of the total expense of green hydrogen (~80 %). The decline of electricity and electrolyser prices are key in driving down the overall costs. In addition by-product oxygen is also considered in the model to assess its economic benefits. We found that by-product oxygen sales could partly reduce the total expense of green hydrogen (~12 % at a price of USD 85/t) but it also should be noted that the volatile price of oxygen may pose uncertainties and risks to the effectiveness of the offset. Since the case study may represent the favourable conditions in China due to the abundant renewable energy resources and large-scale ammonia industry in this region we propose to take a moderate step towards green ammonia production and policies should be focused on reducing the electricity price and capital investments in green hydrogen production. We assume the findings and implications are informative to planning future green ammonia production in China.

Implementation of the hydrogen economy for emission reduction will require storage facilitiesand underground hydrogen storage (UHS) in porous media offers a readily available large-scale option. Lack ofstudies on multiphase hydrogen flow in porous media is one of the several barriers for accurate predictions ofUHS. This paper reports for the first time measurements of hysteresis in hydrogen-water relative permeabilityin a sandstone core under shallow storage conditions. We use the steady state technique to measure primarydrainage imbibition and secondary drainage relative permeabilities and extend laboratory measurements withnumerical history matching and capillary pressure measurements to cover the whole mobile saturation range.We observe that gas and water relative permeabilities show strong hysteresis and nitrogen as substitute forhydrogen in laboratory assessments should be used with care. Our results serve as calibrated input to field scalenumerical modeling of hydrogen injection and withdrawal processes during porous media UHS.

The interest in hybrid polymer electrolyte membrane fuel cells (PEMFC) fuelled by hydrogen in shipping has seen an unprecedented growth in the last years as it could allow zero-emission navigation. However technical safety and regulatory barriers in PEMFC ship design and operation are hampering the use of such systems on a large scale. While several studies analyse these aspects a comprehensive and up-to-date overview on hydrogen PEMFCs for shipping is missing. Starting from the survey of past/ongoing projects on FCs in shipping this paper presents an extensive review on maritime hydrogen PEMFCs outlining the state of the art and future trends for hydrogen storage and bunkering powertrain and regulations. In addition to the need for a clear regulatory framework future studies should investigate the development of an efficient fuel supply chain and bunkering facilities ashore. As for the onboard power system health-conscious energy management low-temperature heat recovery and advancements in fuel processing have emerged as hot research topics.

In order to adopt water electrolyzers as a main hydrogen production system it is critical to develop inexpensive and earth-abundant catalysts. Currently both half-reactions in water splitting depend heavily on noble metal catalysts. This review discusses the proton exchange membrane (PEM) water electrolysis (WE) and the progress in replacing the noble-metal catalysts with earth-abundant ones. The efforts within this field for the discovery of efficient and stable earth-abundant catalysts (EACs) have increased exponentially the last few years. The development of EACs for the oxygen evolution reaction (OER) in acidic media is particularly important as the only stable and efficient catalysts until now are noble-metal oxides such as IrOx and RuOx. On the hydrogen evolution reaction (HER) side there is significant progress on EACs under acidic conditions but there are very few reports of these EACs employed in full PEM WE cells. These two main issues are reviewed and we conclude with prospects for innovation in EACs for the OER in acidic environments as well as with a critical assessment of the few full PEM WE cells assembled with EACs.

In response to the global challenge of climate change 136 countries accounting for 90% of global GDP and 85% of the population have now set net-zero targets. A transition to net-zero will require the decarbonization of all sectors of the economy. Green-hydrogen produced from renewable energy sources poses little to no threat to the environment and increasing its production will support net-zero targets Our study examined the evolution of green-hydrogen research themes since the UN Sustainable Development Goals were adopted in 2015 by utilizing bibliographic couplings keyword co-occurrence and keyphrase analysis of 642 articles from 2016 to 2021 in the Scopus database. We studied bibliometrics indicators and temporal evolution of publications and citations patterns of open access the effect of author collaboration influential publications and top contributing countries. We also consider new indicators like publication views keyphrases topics with prominence and field weighted citation impact and Altmetrics to understand the research direction further. We find four major thematic distributions of green-hydrogen research based on keyword co-occurrence networks: hydrogen storage hydrogen production electrolysis and the hydrogen economy. We also find networks of four research clusters that provide new information on the journal’s contributions to green-hydrogen research. These are materials chemistry hydrogen energy and cleaner production applied energy and fuel cells. Most green-hydrogen research aligns with Affordable and Clean Energy (SDG 7) and Climate Action (SDG 13). The outcomes of policy decisions in the United States Europe India and China will profoundly impact green-hydrogen production and storage over the next five years. If these policies are implemented these countries will account for two-thirds of this growth. Asia will account for the most significant part and become the second-largest producer globally.

Hydrogen production using solar energy is an important way to obtain hydrogen energy. However the inherent intermittent and random characteristics of solar energy reduce the efficiency of hydrogen production. Therefore it is necessary to add an energy storage system to the photovoltaic power hydrogen production system. This paper establishes a model of a photovoltaic power generation hydrogen system and optimizes the capacity configuration. Firstly the mathematical model is modeled and analyzed and the system is modeled using Matlab/Simulink; secondly the principle of optimal configuration of energy storage capacity is analyzed to determine the optimization strategy we propose the storage capacity configuration algorithm based on the low-pass filtering principle and optimal time constant selection; finally a case study is conducted whose photovoltaic installed capacity of 30 MW verifying the effectiveness of the proposed algorithm analyzing the relationship between energy storage capacity and smoothing effect. The results show that as the cut-off frequency decreases the energy storage capacity increases and the smoothing effect is more obvious. The proposed algorithm can effectively reduce the 1 h maximum power variation of PV power generation. In which the maximum power variation of PV generation 1 h before smoothing is 4.31 MW. We set four different sets of time constants the maximum power variation of PV generation 1 h after smoothing is reduced to 0.751 0.389 0.078 and 0.04 MW respectively.

Polymer electrolyte membrane (PEM) fuel cells are electrochemical devices that directly convert the chemical energy stored in fuel into electrical energy with a practical conversion efficiency as high as 65%. In the past years significant progress has been made in PEM fuel cell commercialization. By 2019 there were over 19000 fuel cell electric vehicles (FCEV) and 340 hydrogen refueling stations (HRF) in the U.S. (~8000 and 44 respectively) Japan (~3600 and 112 respectively) South Korea (~5000 and 34 respectively) Europe (~2500 and 140 respectively) and China (~110 and 12 respectively). Japan South Korea and China plan to build approximately 3000 HRF stations by 2030. In 2019 Hyundai Nexo and Toyota Mirai accounted for approximately 63% and 32% of the total sales with a driving range of 380 and 312 miles and a mile per gallon (MPGe) of 65 and 67 respectively. Fundamentals of PEM fuel cells play a crucial role in the technological advancement to improve fuel cell performance/durability and reduce cost. Several key aspects for fuel cell design operational control and material development such as durability electrocatalyst materials water and thermal management dynamic operation and cold start are briefly explained in this work. Machine learning and artificial intelligence (AI) have received increasing attention in material/energy development. This review also discusses their applications and potential in the development of fundamental knowledge and correlations material selection and improvement cell design and optimization system control power management and monitoring of operation health for PEM fuel cells along with main physics in PEM fuel cells for physics-informed machine learning. The objective of this review is three fold: (1) to present the most recent status of PEM fuel cell applications in the portable stationary and transportation sectors; (2) to describe the important fundamentals for the further advancement of fuel cell technology in terms of design and control optimization cost reduction and durability improvement; and (3) to explain machine learning physics-informed deep learning and AI methods and describe their significant potentials in PEM fuel cell research and development (R&D).

This paper discusses fuel cell electric vehicles and more specifically the challenges and development of hydrogen-fueled buses for people accessing this transportation in cities and urban environments. The study reveals the main innovations and challenges in the field of hydrogen bus deployment and identifies the most common approaches and errors in this area by extracting and critically appraising data from sources important to the energy perspective. Three aspects of the development and horizons of fuel cell electric buses are reviewed namely energy consumption energy efficiency and energy production. The first is associated with the need to ensure a useful and sustainable climate-neutral public transport. Herewith the properties of the hydrogen supply of electric buses and their benefits over gasoline gas and battery vehicles are discussed. The efficiency issue is related to the ratio of consumed and produced fuel in view of energy losses. Four types of engines–gasoline diesel gas and electrical–are evaluated in terms of well-to-wheel tank-to-wheel delivery and storage losses. The third problem arises from the production operating and disposal constraints of the society at the present juncture. Several future-oriented initiatives of the European Commission separate countries and companies are described. The study shows that the effectiveness of the FCEBs depends strongly on the energy generation used to produce hydrogen. In the countries where the renewables are the main energy sources the FCEBs are effective. In other regions they are not effective enough yet although the future horizons are quite broad.

The decarbonisation of heat supply will play a critical role in meeting the emissions reduction target. There is however great uncertainty associated with the achievable levels of heat decarbonisation and the optimal heat technology mix which can have serious implications for the future electricity and gas demand. This work employs an integrated gas electricity and heat supply model to quantify the impacts of heat decarbonisation pathways on the future electricity and gas demand. A case study in the Great Britain is performed considering two heat decarbonisation scenarios in 2050: one is the predominantly electrified heat supply and the other is the predominantly hydrogen-based heat supply. The electricity demand becomes more volatile in the electrified heat scenario as the peak surges to 107.3 GW compared to 51.1 GW in the 2018 reference scenario while the peak in hydrogen-based heat scenario is 78.4 GW. The peak gas demand declines from 247.6 GW for 2018 to 81.7 GW for electrified heat scenario and to 85.1 GW for hydrogen-based heat scenario confirming that the seasonality associated with heat demand is shifting away from the gas network and towards electricity network. Moreover a sensitivity analysis shows that the future electricity demand is highly sensitive to parameters such as relative heat demand coefficient of performance of air source heat pumps and share of electricity in hydrogen production. Finally the application of a load shifting strategy demonstrates that demand-side flexibility has the potential to maintain the electricity system balance and minimise the generation and network infrastructure requirements arising from heat electrification. While the case study presented in this paper is based on the Great Britain the findings regarding the future electricity and gas demand are relevant for the global energy transition.

One of the strategic goals of developed countries is to significantly increase the share of renewable energy sources in electricity generation. However the process may be hindered by e.g. the storage and transport of energy from renewable sources. The European Union countries see the development of the hydrogen economy as an opportunity to overcome this barrier. Therefore since 2020 the European Union has been implementing a hydrogen strategy that will increase the share of hydrogen in the European energy mix from the current 2 percent to up to 13–14 percent by 2050. In 2021 following the example of other European countries the Polish government adopted the Polish Hydrogen Strategy until 2030 with an outlook until 2040 (PHS). However the implementation of the strategy requires significant capital expenditure and infrastructure modernisation which gives rise to question as to whether Poland is likely to achieve the goals set out in the Polish Hydrogen Strategy and European Green Deal. The subject of the research is an analysis of the sources of financing for the PHS against the background of solutions implemented by the EU countries and a SWOT/TOWS analysis on the hydrogen economy in Poland. The overall result of the SWOT/TOWS analysis shows the advantage of strengths and related opportunities. This allows for a positive assessment of the prospects for the hydrogen economy in Poland. Poland should continue its efforts to take advantage of the external factors (O/S) such as EU support an increased price competitiveness of hydrogen and the emergence of a competitive cross-border hydrogen market in Europe. At the same time the Polish authorities should not forget about the weaknesses and threats that may inhibit the development of the domestic hydrogen market. It is necessary to modernise the infrastructure; increase the share of renewable energy sources in hydrogen production; increase R&D expenditure and in particular to complete the negotiations related to the adoption of the Fit for 55 package.

Hydrogen is one of the prospective clean energies that could potentially address two pressing areas of global concern namely energy crises and environmental issues. Nowadays fossil‐ based technologies are widely used to produce hydrogen and release higher greenhouse gas emis‐ sions during the process. Decarbonizing the planet has been one of the major goals in the recent decades. To achieve this goal it is necessary to find clean sustainable and reliable hydrogen pro‐ duction technologies with low costs and zero emissions. Therefore this study aims to analyse the hydrogen generation from solar and wind energy sources and observe broad prospects with hybrid renewable energy sources in producing green hydrogen. The study mainly focuses on the critical assessment of solar wind and hybrid‐powered electrolysis technologies in producing hydrogen. Furthermore the key challenges and opportunities associated with commercial‐scale deployment are addressed. Finally the potential applications and their scopes are discussed to analyse the important barriers to the overall commercial development of solar‐wind‐based hydrogen production systems. The study found that the production of hydrogen appears to be the best candidate to be employed for multiple purposes blending the roles of fuel energy carrier and energy storage modality. Further studies are recommended to find technical and sustainable solutions to overcome the current issues that are identified in this study.

Replacing fossil fuels with energy sources and carriers that are sustainable environmentally benign and affordable is amongst the most pressing challenges for future socio-economic development. To that goal hydrogen is presumed to be the most promising energy carrier. Electrocatalytic water splitting if driven by green electricity would provide hydrogen with minimal CO2 footprint. The viability of water electrolysis still hinges on the availability of durable earth-abundant electrocatalyst materials and the overall process efficiency. This review spans from the fundamentals of electrocatalytically initiated water splitting to the very latest scientific findings from university and institutional research also covering specifications and special features of the current industrial processes and those processes currently being tested in large-scale applications. Recently developed strategies are described for the optimisation and discovery of active and durable materials for electrodes that ever-increasingly harness first principles calculations and machine learning. In addition a technoeconomic analysis of water electrolysis is included that allows an assessment of the extent to which a large-scale implementation of water splitting can help to combat climate change. This review article is intended to cross-pollinate and strengthen efforts from fundamental understanding to technical implementation and to improve the ‘junctions’ between the field’s physical chemists materials scientists and engineers as well as stimulate much-needed exchange among these groups on challenges encountered in the different domains.

Hydrogen energy is an important technical route to achieve carbon peak and carbon neutrality. Direct injection hydrogen engine is one of the ways of hydrogen energy application. It has the advantages of high thermal efficiency and limit/reduce abnormal combustion phenomena. In order to explore the cycle characteristics of direct injection hydrogen engine based on a 2.0L direct injection hydrogen engine an experimental study on the cycle characteristics of direct injection hydrogen engine was carried out. The experimental results show that cycle variation increases from 0.67% to 1.02% with the increasing of engine speed. The cycle variation decreases from 1.52% to 0.64% with the increasing of engine load. As the equivalence ratio increases the cycle variation first decreases significantly from 2.52% to 0.35% and then stabilizes. The ignition advance angle has a better angle to minimize the cycle variation. An experimental study on the influence of the start of injection on the cycle variation was carried out. As the engine speed/engine load is 2000rpm/4bar the cycle variation increases from 0.72% to 2.42% with the start of injection changing from -280°CA to -180°CA; then rapidly decreases to 0.99% and then increases to 2.26% with the start of injection changing from -180°CA to -100°CA. The experimental results show that SOI could cause significant influence on cycle variation because of intake valve closing and shortening mixing time and both the process of intake valve closing and lagging the SOI could cause the cycle variation to increase. The SOI remarkably affects the cycle variation at low engine load/equivalence ratio and high engine speed. This study lays the foundation for the follow-up research of hydrogen engine performance matching of the cycle variation.

Mining operations in remote locations rely heavily on diesel fuel for the electricity haulage and heating demands. Such significant diesel dependency imposes large carbon footprints to these mines. Consequently mining companies are looking for better energy strategies to lower their carbon footprints. Renewable energies can relieve this over-reliance on fossil fuels. Yet in spite of their many advantages renewable systems deployment on a large scale has been very limited mainly due to the high battery storage system. Using hydrogen for energy storage purposes due to its relatively cheaper technology can facilitate the application of renewable energies in the mining industry. Such cost-prohibitive issues prevent achieving 100% penetration rate of renewables in mining applications. This paper offers a novel integrated renewable–multi-storage (wind turbine/battery/fuel cell/thermal storage) solution with six different configurations to secure 100% off-grid mining power supply as a stand-alone system. A detailed comparison between the proposed configurations is presented with recommendations for implementation. A parametric study is also performed identifying the effect of different parameters (i.e. wind speed battery market price and fuel cell market price) on economics of the system. The result of the present study reveals that standalone renewable energy deployment in mine settings is technically and economically feasible with the current market prices depending on the average wind speed at the mine location.

The combination of methane steam reforming technology and CCS (Carbon Capture and Storage) technology has great potential to reduce carbon emissions in the process of hydrogen production. Different from the traditional idea of capturing CO2 (Carbon Dioxide) in the exhaust gas with high work consumption this study simultaneously focuses on CO2 separation from fuel gas and recycling. A new hydrogen production system is developed by methane steam reforming coupled with carbon capture. Separated and captured high-purity carbon dioxide could be recycled for methane dry reforming; on this basis a new methane-dry-reforming-driven hydrogen production system with a carbon dioxide reinjection unit is innovatively proposed. In this study the energy flow and irreversible loss in the two newly developed systems are analyzed in detail through energy and exergy balance analysis. The advantages are explored from the perspective of hydrogen production rate natural gas consumption and work consumption. In addition in consideration of the integrated performance an optimal design analysis was conducted. In terms of hydrogen production the new system based on dry reforming is better with an advantage of 2.41%; however it is worth noting that the comprehensive thermal performance of the new steam reforming system is better reaching 10.95%. This study provides new ideas for hydrogen production from a low carbon emission perspective and also offers a new direction for future distributed energy system integration.

This paper describes the implementation of a hydrogen-based system for an autonomous surface vehicle in an effort to reduce environmental impact and increase driving range. In a suitable computational environment the dynamic electrical model of the entire hybrid powertrain consisting of a proton exchange membrane fuel cell a hydrogen metal hydride storage system a lithium battery two brushless DC motors and two control subsystems is implemented. The developed calculation tool is used to perform the dynamic analysis of the hybrid propulsion system during four different operating journeys investigating the performance achieved to examine the obtained performance determine the feasibility of the work runs and highlight the critical points. During the trips the engine shows fluctuating performance trends while the energy consumption reaches 1087 Wh for the fuel cell (corresponding to 71 g of hydrogen) and 370 Wh for the battery consuming almost all the energy stored on board.

Hydrogen is a renewable energy source with various features clean carbon-free high energy density which is being recognized internationally as a “future energy.” The US the EU Japan South Korea China and other countries or regions are gradually clarifying the development position of hydrogen. The rapid development of the hydrogen energy industry requires more hydrogenation infrastructure to meet the hydrogenation need of hydrogen fuel cell vehicles. Nevertheless due to the frequent occurrence of hydrogen infrastructure accidents their safety has become an obstacle to large-scale construction. This paper analyzed five sizes (diameters of 0.068 mm 0.215 mm 0.68 mm 2.15 mm and 6.8 mm) of hydrogen leakage in the hydrogen fueling station using Quantitative Risk Assessment (QRA) and HyRAM software. The results show that unignited leaks occur most frequently; leaks caused by flanges valves instruments compressors and filters occur more frequently; and the risk indicator of thermal radiation accident and structure collapse accident caused by over-pressure exceeds the Chinese individual acceptable risk standard and the risk indicator of a thermal radiation accident and head impact accident caused by overpressure is below the Chinese standard. On the other hand we simulated the consequences of hydrogen leak from the 45 MPa hydrogen storage vessels by the physic module of HyRAM and obtained the ranges of plume dispersion jet fire radiative heat flux and unconfined overpressure. We suggest targeted preventive measures and safety distance to provide references for hydrogen fueling stations’ safe construction and operation.

Hydrogen is often suggested as a universal fuel that can replace fossil fuels. This paper analyses the feasibility of direct hydrogen utilisation in all energy sectors in a 100% renewable energy system for Europe in 2050 using hour-by-hour energy system analysis. Our results show that using hydrogen for heating purposes has high costs and low energy efficiency. Hydrogen for electricity production is beneficial only in limited quantities to restrict biomass consumption but increases the system costs due to losses. The transport sector results show that hydrogen is an expensive alternative to liquid e-fuels and electrified transport due to high infrastructure costs and respectively low energy efficiency. The industry sector may benefit from hydrogen to reduce biomass at a lower cost than in the other energy sectors but electrification and e-methane may be more feasible. Seen from a systems perspective hydrogen will play a key role in future renewable energy systems but primarily as e-fuel feedstock rather than direct end-fuel in the hard-to-abate sectors.

Hydrogen production from renewable energy is gaining increasing attention to enhance energy consumption structure and foster a more eco-friendly and sustainable society. At the same time mixing hydrogen with natural gas and supplying it to civilians is one of the best ways to reduce carbon emissions and increase the reliability of technology while reducing the costs of storing and transporting hydrogen. Even though numerous researchers have conducted experimental and simulation studies on hydrogen-doped natural gas most of these studies have focused on the effects of hydrogen-doped ratio equivalence ratio and fuel combustion mode. The impact of burner structure on hydrogen-enriched natural gas has not received much attention. Compared with conventional direct-flow combustion swirl combustion can improve the mixing effect of the fuel mixture during combustion and the use of regions of reversed flow due to swirl can make the fuel burn more fully to achieve the reduction of pollutant emissions. Swirling flames are widely used in gas turbines and industrial furnaces because of their high stability. However the application of swirl combustion in domestic equipment is still in its infancy which deserves more researchers to explore and enhance the working conditions of domestic combustion equipment. In this paper a three-dimensional swirl burner model is utilized to examine the effect of swirl angle θ and swirl length L of the swirler on the combustion behavior of hydrogen-enriched natural gas in a swirl burner. The results indicate that the swirl angle θ and swirl length L play an essential role in the combustion of natural gas containing hydrogen. As the swirl angle θ increases the flame temperature decreases more slowly the combustion becomes more stable and the length of the flame is slightly increased. Simultaneously CO and NO emissions will gradually decrease and the combustion effect is enhanced when the swirl angle is 45◦. With increased swirl length L the flame length grows the high-temperature region expands and CO and NO emissions decrease. Meanwhile the change in swirl length has little effect on the increase of flame peak temperature when the fuel is thoroughly mixed. When the swirl length is 12 mm CO and NO emissions are lower and NO emissions are reduced by 36.11% compared to a swirl length of 6 mm. This work is a reference point for applying hydrogen-mixed natural gas in the swirl burner but it must be studied and optimized further in future research.

Carbon dioxide is an important medium of the global carbon cycle and has the dual properties of realizing the conversion of organic matter in the ecosystem and causing the greenhouse effect. The fixed or available carbon dioxide in the atmosphere is defined as “gray carbon” while the carbon dioxide that cannot be fixed or used and remains in the atmosphere is called “black carbon”. Carbon neutral is the consensus of human development but its implementation still faces many challenges in politics resources technology market and energy structure etc. It is proposed that carbon replacement carbon emission reduction carbon sequestration and carbon cycle are the four main approaches to achieve carbon neutral among which carbon replacement is the backbone. New energy has become the leading role of the third energy conversion and will dominate carbon neutral in the future. Nowadays solar energy wind energy hydropower nuclear energy and hydrogen energy are the main forces of new energy helping the power sector to achieve low carbon emissions. “Green hydrogen” is the reserve force of new energy helping further reduce carbon emissions in industrial and transportation fields. Artificial carbon conversion technology is a bridge connecting new energy and fossil energy effectively reducing the carbon emissions of fossil energy. It is predicted that the peak value of China’s carbon dioxide emissions will reach 110108 t in 2030. The study predicts that China's carbon emissions will drop to 22108 t 33108 t and 44108 t respectively in 2060 according to three scenarios of high medium and low levels. To realize carbon neutral in China seven implementation suggestions have been put forward to build a new “three small and one large” energy structure in China and promote the realization of China's energy independence strategy.

Human activities have exacerbated global greenhouse effects resulting in extreme climate changes that have caused disasters and food and water shortages in recent years. Transport activities are the one of the main causes of global greenhouse gas (GHG) emissions. Therefore policy makers must develop some strategies to reduce GHG emissions. One of the Taiwan’s transportation policies intended to reduce CO2 emissions is to replace all traditional diesel fuel urban buses with alternative energy buses. This paper uses a case study of bus route NO. 2 in Tainan City and follows the international standard ISO/TS 14067 and PAS2050 to measure the carbon footprints of different energy buses. The purpose is to measure the environmental benefits of alternative energy buses. The results of the bus carbon footprints from high to low were LNG buses 63.14g CO2e/pkm; traditional diesel buses 54.6g CO2e/pkm; liquefied petroleum gas buses 47.4g CO2e/pkm; plug-in electric buses 37.82g CO2e/pkm and hydrogen fuel cell bus es 29.17g CO2e/pkm respectively. It was also found that the use of hydrogen fuel cell buses would potentially reduce CO2e emissions in Tainan City by 1244081 tons which at this time is only city bus No. 2. If all the Taiwan city buses were switched to hydrogen fuel cell buses this would potentially reduce CO2e by 227832.39 tons. The effect of the reduction in carbon emissions from the use of hydrogen fuel cells buses in all Taiwanese urban areas is the equivalent of planting 22.78 million trees. It is thus suggested that the government use hydrogen fuel cell buses as the future of the country’s major alternative energy buses since they are the most environmentally friendly alternative to reducing CO2 emissions.

On this episode of Everything About Hydrogen we chat with Andrew Cunningham Founder and Director at GeoPura. GeoPura is enabling the production transport and use of zero-emissions fuels with innovative and commercially viable technology to decarbonise the global economy. As the world transitions away from fossils fuels there is an increasing need for reliable clean electricity. If global power demand continues to grow as expected the electricity grid system will need support from renewable energy sources such as hydrogen and fuel cell power generator. GeoPura seeks to address exactly that kind of need.

The podcast can be found on their website

Island energy systems are becoming an important part of energy transformation due to the growing needs for the penetration of renewable energy. Among the possible systems a combination of different energy generation technologies is a viable option for local users as long as energy storage is implemented. The presented paper describes an energy-economic assessment of an island system with a photovoltaic field small wind turbine wood chip gasifier battery and hydrogen circuit with electrolyzer and fuel cell. The system is designed to satisfy the electrical energy demand of a tourist facility in two European localizations. The operation of the system is developed and dynamically simulated in the Transient System Simulation (TRNSYS) environment taking into account realistic user demand. The results show that in Gdansk Poland it is possible to satisfy 99% of user demand with renewable energy sources with excess energy equal to 31% while in Agkistro Greece a similar result is possible with 43% of excess energy. Despite the high initial costs it is possible to obtain Simple Pay Back periods of 12.5 and 22.5 years for Gdansk and Agkistro respectively. This result points out that under a high share of renewables in the energy demand of the user the profitability of the system is highly affected by the local cost of energy vectors. The achieved results show that the system is robust in providing energy to the users and that future development may lead to an operation based fully on renewables.

Hydrogen fuel in internal combustion engine gives a very big advantage to the transportation sector especially in solving the greenhouse emission problem. However there are only few research discovered the ability of argon as a working gas in hydrogen combustion in internal combustion engine. The high temperature rises from the argon compression tend to result in heat loss problem. This research aims to study the heat loss mechanism on wall surface condition in the combustion chamber. Experiments were conducted to study the effects of different heat flux sensor locations and the effect of ignition delay on heat flux. Local heat flux measurement was collected and images were observed using high speed shadowgraph images. The ignition delay that occurred near the combustion wall will result in larger heat loss throughout the combustion process. Higher ambient pressure results in a bigger amount of heat flux value. Other fundamental characteristics were obtained and discussed which may help in contributing the local heat loss data of an argon-circulated hydrogen engine in future engine operation.

With the constant increase in variable renewable energy production in electricity and district heating systems integration with the gas system is a way to provide flexibility to the overall energy system. In the sustainable transition towards a zero-emission energy system traditional natural gas can be substituted by renewable gasses derived from anaerobic digestion or thermal gasification and hydrogen. In this paper we present a methodology for modelling renewable gas options and limits on biomass resources across sectors in the energy optimisation model Balmorel. Different scenarios for socio-economic pathways to emission neutral electricity and district heating systems in Denmark Sweden Norway and Germany show that a renewable based energy system benefits from a certain percentage of gas as a supplement to other flexibility options like interconnectors. Especially upgraded biogas from anaerobic digestion serves as a substitute for natural gas in all scenarios. Allocating only 10% of available biomass to the electricity and district heating sector leads to full exploitation of the scarce biomass resource by boosting biogas and syngas with hydrogen. The need for renewable gasses is highest in Germany and least in Norway where hydro-power provides flexibility in terms of storable and dispatchable electricity production. The scenarios show that a required ‘‘late sprint" from fossils to achieve a zero-emission energy system in 2050 causes (1) significant higher accumulated emissions and (2) a system which strongly relies on fuels also in an emission free system instead of stronger integration of the electricity and district heating systems through electrification as well as stronger integration of the power systems across countries through interconnectors.

The crisscross progress of transportation and energy carries the migrating track of human society development and the evolution of civilization among which the decarbonization strategy is a key issue. Traffic carbon emissions account for 16.2% of total energy carbon emissions while road traffic carbon emissions account for 11.8% of total energy carbon emissions. Therefore road traffic is a vital battlefield in attaining the goal of decarbonization. Employing clean energy as an alternative fuel is of great significance to the transformation of the energy consumption structure in road transportation. Hydrogen and ammonia are renewable energy with the characteristics of being widely distributed and clean. Both exist naturally in nature and the products of complete combustion are substances (water and nitrogen) that do not pollute the atmosphere. Because it can promote agricultural production ammonia has a long history in human society. Both have the potential to replace traditional fossil fuel energy. An overview of the advantages of hydrogen and ammonia as well as their development in different countries such as the United States the European Union Japan and other major development regions is presented in this paper. Related research topics of hydrogen and ammonia’s production storage and transferring technology have also been analyzed and collated to stimulate the energy production chain for road transportation. The current cost of green hydrogen is between $2.70–$8.80 globally which is expected to approach $2–$6 by 2030. Furthermore the technical development of hydrogen and ammonia as a fuel for engines and fuel cells in road transportation is compared in detail and the tests practical applications and commercial popularization of these technologies are summarized respectively. Opportunities and challenges coexist in the era of the renewable energy. Based on the characteristics and development track of hydrogen and ammonia the joint development of these two types of energy is meant to be imperative. The collaborative development mode of hydrogen and ammonia together with the obstacles to their development of them are both compared and discussed. Finally referring to the efforts and experiences of different countries in promoting hydrogen and ammonia in road transportation corresponding constructive suggestions have been put forward for reference. At the end of the paper a framework diagram of hydrogen and ammonia industry chains is provided and the mutual promotion development relationship of the two energy sources is systematically summarized.

As an important component of hydrogen fuel cell vehicles the air compressor with an air foil bearing rotates at tens of thousands of revolutions per minute. The heat generation concentration problem caused by the high-speed motor loss seriously affects the safe and normal operation of the motor so it is very important to clarify the loss distribution of the high-speed motor and adopt a targeted loss reduction design for air compressor heat dissipation. In this paper for an air compressor with a foil bearing with a rated speed of 80000 rpm an empirical formula and a three-dimensional transient magnetic field finite element model are used to model and calculate the air friction loss stator core loss winding loss and permanent magnet eddy current loss. The accuracy of the analytical calculation method is verified by torque test experiments under different revolutions and the average simulation accuracy can reach 91.1%. Then the distribution of the air friction loss stator core loss winding loss and eddy current loss of the air compressor motor at different revolutions is obtained by using this method. The results show that the proposed method can effectively calculate the motor rotor loss of a high-speed air compressor with air foil bearing. Although the motor efficiency increases with the increase in motor speed the absolute value of loss also increases with the increase in motor speed. Stator core loss and air friction loss are the main sources of loss accounting for 55.64% and 29% of the total motor loss respectively. The electromagnetic loss of winding the eddy current and other alloys account for a relatively small proportion which is 15% in total. The conclusions obtained in this paper can effectively guide calculations of motor loss the motor heat dissipation design of a high-speed air compressor with an air foil bearing.

This paper discusses the potential for green-hydrogen production in a run-of-river 9 hydropower plant. This particular hydropower plant has no significant water accumulation but 10 there is the potential for limited hydrogen production due to a mismatch between the daily 11 predefined electricity production (known as the timetable) and the actual water inflows. The 12 timetable for the hydropower plant is prepared by the operator of the electro-energetic system 13 based on a model of the available production capacities forecasted consumption water 14 accumulation state of the river flows weather forecasts and the system operator’s strategy. The 15 uncertainty in the model’s input parameters is reflected in the output timetable for the 16 hydropower plant and for this reason a small reserve of water for potential exploitation is 17 envisaged. By using real data for the timetable and the water inflow we estimate the excess 18 hydropower that can be used for hydrogen cogeneration. Since the primary task of the 19 hydropower plant is to produce electricity according to the timetable the production of 20 hydrogen is only possible to a limited extent. Therefore we present a control algorithm that 21 regulates the amount of hydrogen production while considering the predefined timetable and 22 the real water accumulation. The second part of the paper deals with the economic viability of 23 hydrogen cogeneration in the case-study run-of-river hydropower plant and discusses the 24 possibility of using it for local public transport.

As a fuel for power generation high-pressure hydrogen gas is widely used for transportation and its efficient storage promotes the development of fuel cell vehicles (FCVs). However as the filling process takes such a short time the maximum temperature in the storage tank usually undergoes a rapid increase which has become a thorny problem and poses great technical challenges to the steady operation of hydrogen FCVs. For security reasons SAE J2601/ISO 15869 regulates a maximum temperature limit of 85 ◦C in the specifications for refillable hydrogen tanks. In this paper a two-dimensional axisymmetric and a three-dimensional numerical model for fast charging of Type III 35 MPa and 70 MPa hydrogen vehicle cylinders are proposed in order to effectively evaluate the temperature rise within vehicle tanks. A modified standard k-ε turbulence model is utilized to simulate hydrogen gas charging. The equation of state for hydrogen gas is adopted with the thermodynamic properties taken from the National Institute of Standards and Technology (NIST) database taking into account the impact of hydrogen gas’ compressibility. To validate the numerical model three groups of hydrogen rapid refueling experimental data are chosen. After a detailed comparison it is found that the simulated results calculated by the developed numerical model are in good agreement with the experimental results with average temperature differences at the end time of 2.56 K 4.08 K and 4.3 K. The present study provides a foundation for in-depth investigations on the structural mechanics analysis of hydrogen gas vessels during fast refueling and may supply some technical guidance on the design of charging experiments.

This opinion piece describes how the optimal integration of hydrogen-fuel-cell with battery in a heavy highly-utilised vehicle can extend vehicle range while cutting refuelling time and reducing cost compared to a pure battery electric vehicle.

In this podcast David Ledesma talks with Rahmat Poudineh Senior Research Fellow and Aliaksei Patonia Research Fellow on issues and options with respect to long distance transportation of the hydrogen.

Hydrogen currently is mainly a local or regional commodity. If hydrogen is to become a truly global-traded commodity it needs to be transported over long transoceanic distances in an economical way. However unlike natural gas shipping compressed or liquefied hydrogen over long distances is very inefficient and expensive. At the same time hydrogen can be converted into multiple carriers with a higher energy density and higher transport capacity such as liquid ammonia toluene/methylcyclohexane (MCH) or methanol. These chemicals have their own advantages and drawbacks and their techno-economic characteristics in terms of boil-off gas and thermodynamic and conversion losses play a key role in the efficiency of transoceanic transportation of the hydrogen.

On the other hand apart from techno-economic features there are other factors to consider for long distance transportation of the hydrogen via its careers. Here such issues as safety public acceptance as well as legal and regulatory constraints may come into play. Another factor is the availability of the industries and infrastructures already developed around any of possible hydrogen carriers as well as their potential industrial applicability beyond hydrogen. Finally technological progress in other decarbonization applications and most importantly full commercialization of CCUS solutions is likely to dramatically change the approach towards long distance hydrogen transportation.

The podcast can be found on their website. 

On today’s episode of Everything About Hydrogen we are speaking with Dan Sadler Vice President for UK Low Carbon Solutions at Equinor. Equinor is of course a giant in the global energy sector and is taking a prominent role in the development of the international hydrogen economy with high-profile investments in a number of large-scale production projects in major markets such as the UK. Dan has spent the better part of a decade focused on how to leverage hydrogen’s potential as a fuel for the energy transition and we are excited to have him with us to discuss how Equinor is deploying hydrogen technologies and how he and Equinor expect hydrogen to play a role in a decarbonized energy future.

The podcast can be found on their website.

Countries such as China are facing a bottleneck in their paths to carbon neutrality: abating emissions in heavy industries and heavy-duty transport. There are few in-depth studies of the prospective role for clean hydrogen in these ‘hard-to-abate’ (HTA) sectors. Here we carry out an integrated dynamic least-cost modelling analysis. Results show that first clean hydrogen can be both a major energy carrier and feedstock that can significantly reduce carbon emissions of heavy industry. It can also fuel up to 50% of China’s heavy-duty truck and bus fleets by 2060 and significant shares of shipping. Second a realistic clean hydrogen scenario that reaches 65.7 Mt of production in 2060 could avoid US$1.72 trillion of new investment compared with a no-hydrogen scenario. This study provides evidence of the value of clean hydrogen in HTA sectors for China and countries facing similar challenges in reducing emissions to achieve net-zero goals.

Background: Naval trafc is highly dependent on depleting fossil resources and causes signifcant greenhouse gas emissions. At the same time marine transportation is a major backbone of world trade. Thus alternative fuel concepts are highly needed. Diferent fuels such as ammonia methanol liquefed natural gas and hydrogen have been proposed. For some of them frst prototype vessels have been in operation. However practical experience is still limited. Most studies so far focus on aspects such as efciency and economics. However particularly in marine applications reliability of propulsion systems is of utmost importance because failures on essential ship components at sea pose a huge safety risk. If the respective components lose their functionality repair can be much more challenging due to large distances to dockyards and the complicated transport of spare parts to the ship. Consequently evaluation of reliability should be a core element of system analysis for new marine fuels. Results: In this study reliability was studied for four potential fuels. The analysis involved several steps: estimation of overall failure rates identifcation of most vulnerable components and assessment of criticality by including severity of fault events. On the level of overall failure rate ammonia is shown to be very promising. Extending the view over a pure failure rate-based evaluation shows that other approaches such as LOHC or methanol can be competitive in terms of reliability and risk. As diferent scenarios require diferent weightings of the diferent reliability criteria the conclusion on the best technology can difer. Relevant aspects for this decision can be the availability of technical staf high-sea or coastal operation the presence of non-naval personnel onboard and other factors. Conclusions: The analysis allowed to compare diferent alternative marine fuel concepts regarding reliability. However the analysis is not limited to assessment of overall failure rates but can also help to identify critical elements that deserve attention to avoid fault events. As a last step severity of the individual failure modes was included. For the example of ammonia it is shown that the decomposition unit and the fuel cell should be subject to measures for increasing safety and reducing failure rates.

Renewable energies such as the wind energy and solar energy generate low-carbon electricity which can directly charge battery electric vehicles (BEVs). Meanwhile the surplus electricity can be used to produce the “green hydrogen” which provides zero-emission hydrogen fuels to those fuel cell electric vehicles (FCEVs). In order to charge/refuel multi-energy vehicles we propose a novel scheme of hybrid hydrogen/electricity supply using cryogenic and superconducting technologies. In this scheme the green hydrogen is further liquefied into the high-density and low-pressure liquid hydrogen (LH2) for bulk energy storage and transmission. Taking the advantage of the cryogenic environment of LH2 (20 K) it can also be used as the cryogen to cool down super conducting cables to realize the virtually zero-loss power transmission from 100 % renewable sources to vehicle charging stations. This hybrid LH2/electricity energy pipeline can realize long-distance large-capacity and high efficiency clean energy transmission to fulfil the hybrid energy supply demand for BEVs and FCEVs. For the case of a 100 MW-class hybrid hydrogen/electricity supply station the system principle and energy management strategy are analyzed through 9 different operating sub-modes. The corresponding static and dynamic economic modeling are performed and the economic feasibility of the hybrid hydrogen/electricity supply is verified using life-cycle analysis. Taking an example of wind power capacity 1898 MWh and solar power capacity 1619 MWh per day the dynamic payback period is 15.06 years the profitability index is 1.17 the internal rate of return is 7.956 % and the accumulative NPV is 187.92 M$. The system design and techno-economic analysis can potentially offer a technically/economically superior solution for future multi-energy vehicle charging/refueling systems.

Hydrogen can be key in the energy system transition. We investigate the role of offshore hydrogen generation in a future integrated energy system. By performing energy system optimisation in a model application of the Northern-central European energy system and the North Sea offshore grid towards 2050 we find that offshore hydrogen generation may likely only play a limited role and that offshore wind energy has higher value when sent to shore in the form of electricity. Forcing all hydrogen generation offshore would lead to increased energy system costs. Under the assumed scenario conditions which result in deep decarbonisation of the energy system towards 2050 hydrogen generation – both onshore and offshore – follows solar PV generation patterns. Combined with hydrogen storage this is the most cost-effective solution to satisfy future hydrogen demand. Overall we find that the role of future offshore hydrogen generation should not simply be derived from minimising costs for the offshore sub-system but by also considering the economic value that such generation would create for the whole integrated energy system. We find as a no-regret option to enable and promote the integration of offshore wind in onshore energy markets via electrical connections.

The increasing energy demand and the subsequent climate change consequences are supporting the search for sustainable alternatives to fossil fuels. In this scenario the link between hydrogen and renewable energy is playing a key role and unitized hydrogen-chlorine (H2-Cl2) regenerative cells (RFCs) have become promising candidates for renewable energy storage. Described herein are the recent advances in cell configurations and catalysts for the different reactions that may take place in these systems that work in both modes: electrolysis and fuel cell. It has been found that platinum (Pt)-based catalysts are the best choice for the electrode where hydrogen is involved whereas for the case of chlorine ruthenium (Ru)-based catalysts are the best candidates. Only a few studies were found where the catalysts had been tested in both modes and recent advances are focused on decreasing the amount of precious metals contained in the catalysts. Moreover the durability of the catalysts tested under realistic conditions has not been thoroughly assessed becoming a key and mandatory step to evaluate the commercial viability of the H2-Cl2 RFC technology.

Blending hydrogen with natural gas is emerging as a pivotal strategy in the transition to low-carbon energy systems. However the exploitation of the natural gas infrastructure to distribute natural gas and hydrogen blends (and 100% hydrogen in the long-term) introduces several technical economic and safety issues. These latter are paramount especially in urban distribution networks that supply residential buildings and dwellings since the quality and safety of the living environment can also be significantly affected. In this scenario the reliability of odorant concentration measurements according to the best practices currently in use for natural gas becomes crucial. This study is aimed at assessing the accuracy of odorant measurements at different concentration levels (i.e. low medium and high) in 100% methane methane–hydrogen blend and 100% hydrogen. The obtained results show the tendency to overestimate the odorant concentration up to 2.3% in methane–hydrogen blends at medium and high concentrations of THT as well as the underestimation of −3.4% in 100% hydrogen at low concentration of TBM. These results are consistent with those of natural gas from the city distribution network with hydrogen content of 5% and 20%.

The current research on green hydrogen can focus from the perspective of production but understanding the demand side is equally important to the initial creation of a hydrogen ecosystem in countries with low industrial activities that can utilise large amounts of hydrogen in the short term. Early movers in these countries must create a demand market in parallel with the green hydrogen plant commissioning. This paper presents research that explores the heavy-duty transport sector as a market-of-interest for early deployment of green hydrogen in Ireland. Conducting a survey-based market research amongst this sector indicate significant interest in hydrogen on the island of Ireland and the barriers the participants presented have been overcome in other jurisdictions. The study develops a model to estimate 1.) the annual hydrogen demand and 2.) the corresponding delivery cost to potential hydrogen consumers either directly or to central hydrogen fuelling hubs.

An investigation was conducted to determine the effects of operating parameters for various electrode types on hydrogen gas production through electrolysis as well as to evaluate the efficiency of the polymer electrolyte membrane (PEM) electrolyzer. Deionized (DI) water was fed to a single-cell PEM electrolyzer with an active area of 36 cm2 . Parameters such as power supply (50–500 mA/cm2 ) feed water flow rate (0.5–5 mL/min) water temperature (25−80 ◦C) and type of anode electrocatalyst (0.5 mg/cm2 PtC [60%] 1.5 mg/cm2 IrRuOx with 1.5 mg/cm2 PtB 3.0 mg/cm2 IrRuOx and 3.0 mg/cm2 PtB) were varied. The effects of these parameter changes were then analyzed in terms of the polarization curve hydrogen flowrate power consumption voltaic efficiency and energy efficiency. The best electrolysis performance was observed at a DI water feed flowrate of 2 mL/min and a cell temperature of 70 ◦C using a membrane electrode assembly that has a 3.0 mg/cm2 IrRuOx catalyst at the anode side. This improved performance of the PEM electrolyzer is due to the reduction in activation as well as ohmic losses. Furthermore the energy consumption was optimal when the current density was about 200 mA/cm2 with voltaic and energy efficiencies of 85% and 67.5% respectively. This result indicates low electrical energy consumption which can lower the operating cost and increase the performance of PEM electrolyzers. Therefore the optimal operating parameters are crucial to ensure the ideal performance and durability of the PEM electrolyzer as well as lower its operating costs.