Publications

The holistic green energy transition of non-interconnected islands faces several challenges if all the energy sectors are included i.e. electricity heating/cooling and mobility. On the one hand the penetration of renewable energy systems (RES) is limited due to design restrictions with respect to the peak demand. On the other hand energy-intensive heating and mobility sectors pose significant challenges and may be difficult to electrify. The focus of this study is on implementing a hybrid Wind–PV system on the non-interconnected island of Anafi (Greece) that utilizes surplus renewable energy production for both building heating through heat pumps and hydrogen generation. This comprehensive study aims to achieve a holistic green transition by addressing all three main sectors—electricity heating and transportation. The produced hydrogen is utilized to address the energy needs of the mobility sector (H2 mobility) focusing primarily on public transportation vehicles (buses) and secondarily on private vehicles. The overall RES production was modeled to be 91724 MWh with a RES penetration of 84.68%. More than 40% of the produced electricity from RES was in the form of excess electricity that could be utilized for hydrogen generation. The modeled generated hydrogen was simulated to be more than 40 kg H2/day which could cover all four bus routes of the island and approximately 200 cars for moderate use i.e. traveled distances of less than 25 km/day for each vehicle.

The cement industry is a building block of modern society and currently responsible for around 7% of global and 4% of EU CO2 emissions. While facing global competition and a challenging business environment the EU cement sector needs to decarbonise its production processes to comply with the EU’s ambitious 2030 and 2050 climate targets. This report provides a snapshot of the current cement production landscape and discusses future technologies that are being explored by the sector to decarbonise its processes describing the transformational change the industry faces. This report compiles the current projects and announcements to deploy breakthrough technologies which do require high capital investments. However with 2050 just one investment cycle away the sector needs to commercialise new low-CO2 technologies this decade to avoid the risk of stranded assets. As Portland cement production is highly CO2-intensive and EU plants are already operating close to optimum efficiency the industry appears to be focussing on carbon capture storage and utilisation technologies - while breakthroughs in alternative chemistries are still being explored - to reduce emissions. While the EU has played an important role in supporting early stage R&D for these technologies it is now striving to fill the funding gap for the commercialisation of breakthrough technologies. The recent momentum towards CO2-free cement provides the EU with the opportunity to be a frontrunner in creating markets for green cement.

The formation of green hydrogen from water electrolysis is one of the supreme methodologies for understanding the well-organized consumption of sporadic renewable energies and the carbon-free future. Among the different electrolysis techniques the evolving anion exchange membrane water electrolysis (AEMWE) shows the utmost promise for manufacturing green hydrogen in an inexpensive way. In the present review we establish the most current and noteworthy achievements of AEMWE which include the advancements in increasing the ionic conductivity and understanding the mechanism of degradation of AEM and the most important topics regarding the designing of the electrocatalyst. The crucial issues that affect the AEMWE behavior are highlighted and future constraints and openings are also discussed. Furthermore this review article provides the appreciated strategies for producing extremely dynamic and robust electrocatalysts and evolving the construction of AEMWE equipment.

In this episode Tony Green Hydrogen Director at National Grid and John Williams Head of Hydrogen Expertise Cluster at AFRYManagement Consulting join us to discuss the challenges in implementing hydrogen. Tony is involved in two exciting hydrogen projects: FutureGrid andProject Union. FutureGrid involves building a facility to create a representative whole-network to trial hydrogen. Project Union will develop a UK hydrogen ‘backbone’ joining together clusters around the country potentially creating a 2000km hydrogen network.

In addition to discussing these projects this episode will explore the following issues:

♦ Managing the transition and challenges in repurposing natural gas pipelines to hydrogen

♦ The potential for blending and de-blending hydrogen

♦ The impact of hydrogen on National Grid’s regulatory approach

♦ How to take the first steps towards a hydrogen wholesale market"

The podcast can be found on their website.

Since ammonia and liquid hydrogen are the optional future shipping cargo and fuels the applicability was crucial using the current technologies and expectations. Existing studies for the economic feasibility of the energies had limitations: empirical evaluation with assumptions and insufficiency related to causality. A distorted estimation can result in failure of decision-making or policy in terms of future energy. The present study aimed to evaluate the transportation costs of future energy including ammonia and liquid hydrogen in comparison to LNG for overcoming the limitations. An integrated mathematical model was applied to the investigation for economic feasibility. The transportation costs of the chosen energies were evaluated for the given transportation plan considering key factors: ship speed BOR and transportation plan. The transportation costs at the design speed for LNG and liquid hydrogen were approximately 55 % and 80 % of that for ammonia without considering the social cost due to CO2 emission. Although ammonia was the most expensive energy for transportation ammonia could be an effective alternative due to insensitivity to the transportation plan. If the social cost was taken into account liquid hydrogen already gained competitiveness in comparison to LNG. The advantage of liquid hydrogen was maximized for higher speed where more BOG was injected into main engines.

In this sixth episode Steffan Eldred Hydrogen Innovation Network Knowledge Transfer Manager and Debra Jones Chemistry Knowledge Transfer Manager from Innovate UK KTN discuss why converting waste to hydrogen is so important and explore the hydrogen transition opportunities and challenges in this sector alongside their special guest Rob Dent Senior Research Engineer - Energy Linde and Application Sales Engineer at BOC UK & Ireland.

The podcast can be found on their website.

On this episode of EAH we sat down with Alejandro Oyarce Barnett Chief Technology Officer and Co-Founder at Hystar. Hystar is a technology-focused company specializing in PEM electrolysers for hydrogen production using renewable energy. The company got its start as a spin-off from SINTEF one of Europe’s largest independent research organizations and has raised private funding so the company can focus on production of its high-efficiency PEM units and keep pace with demand for hydrogen generation capacity. Hystar announced on January 11 2023 that the company has closed a Series B funding round of USD 26mn to rapidly scale-up to full commercial operations with an automated GW-capacity production line by 2025.  Alejandro joined us to discuss in more detail the origins of Hystar its technology and the mission at the core of the company.

The podcast can be found on their website.

If Europe is to meet its 2050 decarbonisation objectives a change of paradigm needs to materialise. The energy sector cannot be understood any more as the sum of independent silos consisting of different energy vectors. Indeed a large number of technologies that are essential to meeting our decarbonisation targets are linking systems and markets currently being planned and operated without fully considering the potential benefits of adopting a holistic approach. If this situation is to persist large-scale sub-optimalities are likely to emerge if the planning and operations of the different components of the energy system will not be able to capture synergies and interdependencies between energy vectors and markets. Interlinkages between systems are appearing between all vectors both at the planning and operation levels. In the case of hydrogen these links are especially important as hydrogen technologies are linking the electricity methane and heat sectors (via electrolysis and hydrogen turbines repurposing of gas assets and hydrogen boilers respectively). Sector integration can allow to capture benefits both in terms of planning and operations:- The production of electrolytic hydrogen poses important challenges in terms of planning the deployment of renewable energy (RES) and electrolyser capacities in a way that ensures that the overall carbon emissions decrease in an effective and cost-efficient manner. Furthermore key questions related to the benefits of co-locating renewable capacities electrolysers and hydrogen demand centres can only be explored if a holistic perspective is adopted. Finally synergies can also appear if planning decisions are taken jointly between the electricity hydrogen and methane sectors as the optimal set of hydrogen infrastructure projects strongly depends on the ability to source electrolysers (link with the electricity sector) and on the possibility to repurpose part of the current infrastructure (link with the methane sector)- Similarly operational considerations also advocate for an integrated approach as electrolysers can provide important flexibility services to the electricity sector if provided with appropriate price signals. These considerations provide the motivation for this study which aims at performing a detailed examination of planning decisions and operational management of a 2050 power system with a focus on comparing different decarbonisation options for the provision of heat of different temperature levels.

This research work is the novel state-of-the-art technology performed on multi-cylinder SI engine fueled compressed natural gas emulsified fuel and hydrogen as dual fuel. This work predicts the overall features of performance combustion and exhaust emissions of individual fuels based on AVL Boost simulation technology. Three types of alternative fuels have been compared and analyzed. The results show that hydrogen produces 20% more brake power than CNG and 25% more power than micro-emulsion fuel at 1500 r/min which further increases the brake power of hydrogen CNG and micro-emulsions in the range of 25% 20% and 15% at higher engine speeds of 2500–4000 r/min respectively. In addition the brake-specific fuel consumption is the lowest for 100% hydrogen followed by CNG 100% and then micro-emulsions at 1500 r/min. At 2500– 5000 r/min there is a significant drop in brake-specific fuel consumption due to a lean mixture at higher engine speeds. The CO HC and NOx emissions significantly improve for hydrogen CNG and micro-emulsion fuel. Hydrogen fuel shows zero CO and HC emissions and is the main objective of this research to produce 0% carbon-based emissions with a slight increase in NOx emissions and CNG shows 30% lower CO emissions than micro-emulsions and 21.5% less hydrocarbon emissions than micro-emulsion fuel at stoichiometric air/fuel ratio.

This work relates the study of system performance in operational conditions for an isolated micro-grid powered by a photovoltaic system and a wind turbine. The electricity produced and not used by the user will be accumulated in two different storage systems: a battery bank and a hydrogen storage system composed of two PEM electrolyzers four pressurized tanks and a PEM fuel cell. One of the main problems to be solved in the development of isolated micro-grids is the management of the various devices and energy flows to optimize their functioning in particular in relation to the load profile and power produced by renewable energy systems depending on weather conditions. For this reason through the development and implementation of a specific simulation program three different energy management systems were studied to evaluate the best strategy for effectively satisfying user requirements and optimizing overall system efficiency.

Aiming at the synergy between a system’s carbon emission reduction demand and the economy of peak shaving operation in the process of optimizing the flexible resource peaking unit portfolio of a multi-energy power system containing large-scale electric vehicles this paper proposes a low-carbon optimal scheduling model for peak shaving resources in multi-energy power systems considering large-scale access for electric vehicles. Firstly the charging and discharging characteristics of electric vehicles were studied and a comprehensive cost model for electric vehicles heat storage and hydrogen storage was established. At the same time the carbon emission characteristics of multienergy power systems and their emission cost models under specific carbon trading mechanisms were established. Secondly the change characteristics of the system’s carbon emissions were studied and a carbon emission cost model of multi-energy power was established considering the carbon emission reduction demand of the system. Then taking the carbon emission of the system and the peak regulating operation costs of traditional units energy storage and new energy unit as optimization objectives the multi-energy power system peak regulation multi-objective optimization scheduling model was established and NSGA-II was used to solve the scheduling model. Finally based on a regional power grid data in Northeast China the improved IEEE 30 node multi-energy power system peak shaving simulation model was built and the simulation analysis verified the feasibility of the optimal scheduling model proposed in this paper.

Hydrogen is a key enabler of a sustainable society. Refurbishment of the existing natural gas infrastructure for up to 100% H2 is considered one of the most energy- and resource-efficient energy transportation methods. The question remains whether the transportation of 100% H2 with reasonable adaptions of the infrastructure and comparable energy amounts to natural gas is possible. The well-known critical components for refurbishment such as increased compressor power reduced linepack as well as pipeline transport efficiencies and their influencing factors were considered based on thermodynamic calculations with a step-by-step overview. A H2 content of 20–30% results in comparable operation parameters to pure natural gas. In addition to transport in pipelines decentralized H2 production will also play an important role in addressing future demands.

Land available for energy production is limited in cities owing to high population density. To reach the net zero goal cities contributing 70% of overall greenhouse gas emissions need to dramatically reduce emissions and increase self-sufficiency in energy production. Environmental infrastructures such as sewage treatment and incineration plants can be used as energy production facilities in cities. This study attempted to examine the effect of using environmental infrastructure such as energy production facilities to contribute toward the carbon neutrality goal through urban energy systems. In particular since the facilities are suitable for hydrogen supply in cities the analysis was conducted focusing on the possibility of hydrogen production. First the current status of energy supply and demand and additional energy production potential in sewage treatment and incineration plants in Seoul were analyzed. Then the role of these environmental infrastructures toward energy self-sufficiency in the urban system was examined. This study confirmed that the facilities can contribute to the city’s energy self-sufficiency and the achievement of its net-zero goal.

The optimal design of off-grid hybrid renewable energy systems (HRESs) is a challenging task which often involves conflicting goals to be faced. In this work levelized cost of energy (LCOE) and CO2 emissions have been addressed simultaneously by using the ε-constraint method together with the particle swarm optimization (PSO) algorithm. Cost-emissions Pareto fronts of different HRES configurations were developed to gain greater awareness about the potential of renewable-based energy systems in off-grid applications. Various combinations of the following components were investigated: photovoltaic panels wind turbines batteries hydrogen and diesel generators. The hydrogen-based system comprises an electrolyzer to convert the excess renewable energy into hydrogen a pressurized tank for H2 storage and a fuel cell for the reconversion of hydrogen into electricity during renewable energy deficits. Electrolyzer and fuel cell devices were modelled by means of part-load performance curves. Size-dependent costs and component lifetimes as a function of the cumulative operational duty were also considered for a more accurate techno-economic assessment. The proposed methodology was applied to the Froan islands (Norway) which were chosen as a reference case study since they are well representative of many other insular microgrid environments in Northern Europe. Results from the sizing simulations revealed that energy storage devices are key components to reduce the dependency on fossil fuels. In particular the hydrogen storage system is crucial in off-grid areas to enhance the RES penetration and avoid a sharp increase in the cost of energy. Hydrogen in fact allows the battery and RES technologies not to be oversized thanks to its cost-effective long-term storage capability. Concerning the extreme case with no diesel the cheapest configuration which includes both batteries and hydrogen has an LCOE of 0.41 €/kWh. This value is around 35% lower than the LCOE of a system with only batteries as energy storage.

This paper aims to expose the effect of hydrogen on the combustion performance and emissions of a high-speed diesel engine. For this purpose a three-dimensional dynamic simulation model was developed using a reasonable turbulence model and a simplified reaction kinetic mechanism was chosen based on experimental data. The results show that in the hydrogen enrichment conditions hydrogen causes complete combustion of diesel fuel and results in a 17.7% increase in work capacity. However the increase in combustion temperature resulted in higher NOx emissions. In the hydrogen substitution condition the combustion phases are significantly earlier with the increased hydrogen substitution ratio () which is not conducive to power output. However when the is 30% the CO soot and THC reach near-zero emissions. The effect of the injection timing is also studied at an HSR of 90%. When delayed by 10° IMEP improves by 3.4% compared with diesel mode and 2.4% compared with dual-fuel mode. The NOx is reduced by 53% compared with the original dual-fuel mode. This study provides theoretical guidance for the application of hydrogen in rail transportation.

Green hydrogen is set to become the energy carrier of the future provided that production technologies such as electrolysis and solar water splitting can be scaled to global dimensions. Testing these hydrogen technologies on the MW scale requires the development of dedicated new test facilities for which there is no precedent. This perspective highlights the challenges to be met on the path to implementing a test facility for large-scale water electrolysis photoelectrochemical and photocatalytic water splitting and aims to serve as a much-needed blueprint for future test facilities based on the authors’ own experience in establishing the Hydrogen Lab Leuna. Key aspects to be considered are the electricity and utility requirements of the devices under testing the analysis of the produced H2 and O2 and the safety regulations for handling large quantities of H2 . Choosing the right location is crucial not only for meeting these device requirements but also for improving financial viability through supplying affordable electricity and providing a remunerated H2 sink to offset the testing costs. Due to their lower TRL and requirement for a light source large-scale photocatalysis and photoelectrochemistry testing are less developed and the requirements are currently less predictable.

On this episode of Everything About Hydrogen we are speaking with Nashwa Al Rawahy Director of HMR Environmental Consultants based in Muscat Oman with regional offices in the United Arab Emirates.

We are excited to have an expert like Nashwa join us to discuss environmental and social impact studies their value to the communities and projects and the importance of building long term In Country Value (ICV).

The podcast can be found on their website.

This paper provides a comprehensive review of the research progress current state-ofthe-art and future research directions of energy storage systems. With the widespread adoption of renewable energy sources such as wind and solar power the discourse around energy storage is primarily focused on three main aspects: battery storage technology electricity-to-gas technology for increasing renewable energy consumption and optimal configuration technology. The paper employs a visualization tool (CiteSpace) to analyze the existing works of literature and conducts an in-depth examination of the energy storage research hotspots in areas such as electrochemical energy storage hydrogen storage and optimal system configuration. It presents a detailed overview of common energy storage models and configuration methods. Based on the reviewed articles the future development of energy storage will be more oriented toward the study of power characteristics and frequency characteristics with more focus on the stability effects brought by transient shocks. This review article compiles and assesses various energy storage technologies for reference and future research.

Every wind turbine is subject to fluctuations in power generation depending on climatic conditions. When electricity supply exceeds demand wind turbines are forced to implement curtailment causing a reduction in generation efficiency and commercial loss to turbine owners. Since the frequency and amount of curtailment of wind turbines increases as the amount of renewable energy become higher on Jeju Island in South Korea Jeju is configuring a Power to Gas (P2G) water electrolysis system that will be connected to an existing wind farm to use the “wasted energy”. In this study economic analysis was performed by calculating the production cost of green hydrogen and sensitivity analysis evaluated the variance in hydrogen cost depending on several influential factors. Approaches to lower hydrogen costs are necessary for the following reasons. The operating company needs a periodical update of hydrogen sale prices by reflecting a change in the system margin price (SMP) with the highest sensitivity to hydrogen cost. Technical development to reduce hydrogen costs in order to reduce power consumption for producing hydrogen and a decrease in annual reduction rate for the efficiency of water electrolysis is recommended. Discussions and research regarding government policy can be followed to lower the hydrogen cost.

Green hydrogen is a tentative solution for the decarbonisation of hard-to-abate sectors such as steel chemical cement and refinery industries. Green hydrogen is a form of hydrogen gas that is produced using renewable energy sources such as wind or solar power through a process called electrolysis. The green hydrogen supply chain includes several interconnected entities such as renewable energy providers electrolysers distribution facilities and consumers. Although there have been many studies about green hydrogen little attention has been devoted to green hydrogen supply chain risk identification and analysis especially for hard-to-abate sectors in Europe. This research contributes to existing knowledge by identifying and analysing the European region’s green hydrogen supply chain risk factors. Using a Delphi method 7 categories and 43 risk factors are identified based on the green hydrogen supply chain experts’ opinions. The best-worst method is utilised to determine the importance weights of the risk categories and risk factors. High investment of capital for hydrogen production and delivery technology was the highest-ranked risk factor followed by the lack of enough capacity for electrolyser and policy & regulation development. Several mitigation strategies and policy recommendations are proposed for high-importance risk factors. This study provides novelty in the form of an integrated approach resulting in a scientific ranking of the risk factors for the green hydrogen supply chain. The results of this study provide empirical evidence which corroborates with previous studies that European countries should endeavour to create comprehensive and supportive standards and regulations for green hydrogen supply chain implementation.

This paper introduces the concept of a thermal management system (TMS) with integrated on-board power generation capabilities for a Mach 8 hypersonic aircraft powered by liquid hydrogen (LH2). This work developed within the EU-funded STRATOFLY Project aims to demonstrate an opportunity for facing the challenges of hypersonic flight for civil applications mainly dealing with thermal and environmental control as well as propellant distribution and on-board power generation adopting a highly integrated plant characterized by a multi-functional architecture. The TMS concept described in this paper makes benefit of the connection between the propellant storage and distribution subsystems of the aircraft to exploit hydrogen vapors and liquid flow as the means to drive a thermodynamic cycle able on one hand to ensure engine feed and thermal control of the cabin environment while providing on the other hand the necessary power for other on-board systems and utilities especially during the operation of high-speed propulsion plants which cannot host traditional generators. The system layout inspired by concepts studied within precursor EU-funded projects is detailed and modified in order to suggest an operable solution that can be installed on-board the reference aircraft with focus on those interfaces impacting its performance requirements and integration features as part of the overall systems architecture of the plane. Analysis and modeling of the system is performed and the main results in terms of performance along the reference mission profile are discussed.

The development of renewable energy technologies is essential to achieve carbon neutrality. Hydrogen can be stably stored and transported in large quantities to maximize power utilization. Detailed understanding of the characteristics and operating methods of water electrolysis technologies in which naturally intermittent fluctuating power is used directly is required for green hydrogen production because fluctuating power-driven water electrolysis processes significantly differ from industrial water electrolysis processes driven by steady grid power. Thus it is necessary to overcome several issues related to the direct use of fluctuating power. This article reviews the characteristics of fluctuating power and its generation as well as the current status and issues related to the operation conditions water electrolyzer configuration system requirements stack/catalyst durability and degradation mechanisms under the direct use of fluctuating power sources. It also provides an accelerated degradation test protocol method for fair catalyst performance comparison and share of effective design directions. Finally it discusses potential challenges and recommendations for further improvements in water electrolyzer components and systems suitable for practical use suggesting that a breakthrough could be realized toward the achievement of a sustainable hydrogen-based society.

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.

Accommodating renewables on the electricity grid may hinder development opportunities for offshore wind farms (OWFs) as they begin to experience significant curtailment or constraint. However there is potential to combine investment in OWFs with Power-to-Gas (PtG) converting electricity to hydrogen via electrolysis for an alternative/complementary revenue. Using historic wind speed and simulated system marginal costs data this work models the electricity generated and potential revenues of a 504 MW OWF. Three configurations are analysed; (1) all electricity is sold to the grid (2) all electricity is converted to hydrogen and sold and (3) a hybrid system where power is converted to hydrogen when curtailment occurs and/or when the system marginal cost is low with the effect of curtailment analysed in each scenario. These represent the status quo a potential future configuration and an innovative business model respectively. The willingness of an investor to build PtG are determined by changes to the net present value (NPV) of a project. Results suggest that configuration (1) is most profitable and that curtailment mitigation alone is not sufficient to secure investment in PtG. By acting as an artificial floor in the electricity price a hybrid configuration (3) is promising and increases NPV for all hydrogen values greater than €4.2/kgH2. Hybrid system attractiveness increases with curtailment only if the hydrogen value is significantly above the levelised cost of €3.77/kgH2. In order for an investor to choose to pursue configuration (2) the offshore wind farm would have to anticipate 8.5% curtailment and be able to receive €4.5/kgH2 or 25% curtailment and receive €4/kgH2. The capital costs and discount rates are the most sensitive parameters and ambitious combinations of technology improvements could produce a levelised cost of €3/kgH2.

Hydrogen is a versatile energy carrier which can be produced from variety of feedstocks stored and transported in various forms for multi-functional end-uses in transportation energy and manufacturing sectors. Several regional national and supra-national climate policy frameworks emphasize the need value and importance of Fuel cell and Hydrogen (FCH) technologies for deep and sector-wide decarbonization. Despite these multi-faceted advantages familiar and proven FCH technologies such as alkaline electrolysis and proton-exchange membrane fuel cell (PEMFC) often face economic technical and societal barriers to mass-market adoption. There is no single unified standardized and globally harmonized normative definition of costs. Nevertheless the discussion and debates surrounding plausible candidates and/or constituents integral for assessing the economics and value proposition of status-quo as well as developmental FCH technologies are steadily increasing—Life Cycle Costing (LCC) being one of them if not the most important outcome of such exercises.<br/>To that end this review article seeks to improve our collective understanding of LCC of FCH technologies by scrutinizing close to a few hundred publications drawn from representative databases—SCOPUS and Web of Science encompassing several tens of technologies for production and select transportation storage and end-user utilization cases. This comprehensive review forms part of and serves as the basis for the Clean Hydrogen Partnership funded SH2E project whose ultimate goal is the methodical development a formal set of principles and guardrails for evaluating the economic environmental and social impacts of FCH technologies. Additionally the SH2E projects will also facilitate the proper comparison of different FCH technologies whilst reconciling range of technologies methodologies modelling assumptions and parameterization found in existing literature.