Publications
Supply and Demand Drivers of Global Hydrogen Deployment in the Transition Toward a Decarbonized Energy System
Nov 2023
Publication
The role of hydrogen in energy system decarbonization is being actively examined by the research and policy communities. We evaluate the potential “hydrogen economy” in global climate change mitigation scenarios using the Global Change Analysis Model (GCAM). We consider major hydrogen production methods in conjunction with delivery options to understand how hydrogen infrastructure affects its deployment. We also consider a rich set of hydrogen end-use technologies and vary their costs to understand how demand technologies affect deployment. We find that the availability of hydrogen transmission and distribution infrastructure primarily affects the hydrogen production mix particularly the share produced centrally versus on-site whereas assumptions about end-use technology primarily affect the scale of hydrogen deployment. In effect hydrogen can be a source of distributed energy enabled by on-site renewable electrolysis and to a lesser extent by on-site production at industrial facilities using natural gas with carbon capture and storage (CCS). While the share of hydrogen in final energy is small relative to the share of other major energy carriers in our scenarios hydrogen enables decarbonization in difficult-to-electrify end uses such as industrial high-temperature heat. Hydrogen deployment and in turn its contribution to greenhouse gas mitigation increases as the climate objective is tightened.
Semi-Solid Forging Process of Aluminium Alloy Connecting Rods for the Hydrogen Internal Combustion Engine
Jun 2024
Publication
As an important piece of equipment for hydrogen energy application the hydrogen internal combustion engine is helpful for the realization of zero carbon emissions where the aluminum connecting rod is one of the key core components. A semi-solid forging forming process for the 7075 aluminum alloy connecting rod is proposed in this work. The influence of process parameters such as the forging ratio sustaining temperature and duration time on the microstructures of the semi-solid blank is experimentally investigated. The macroscopic morphology metallographic structure and physical properties of the connecting-rod parts are analyzed. Reasonable process parameters for preparing the semi-solid blank are obtained from the experimental results. Under the reasonable parameters the average grain size is 41.48~42.57 µm and the average shape factor is 0.80~0.81. The yield strength and tensile strength improvement ratio of the connecting rod produced by the proposed process are 47.07% and 20.89% respectively.
Hydrogen as a Transition Tool in a Fossil Fuel Resource Region: Taking China’s Coal Capital Shanxi as an Example
Aug 2023
Publication
Because of the pressure to meet carbon neutrality targets carbon reduction has become a challenge for fossil fuel resource-based regions. Even though China has become the most active country in carbon reduction its extensive energy supply and security demand make it difficult to turn away from its dependence on coal-based fossil energy. This paper analyzes the Chinese coal capital—Shanxi Province—to determine whether the green low-carbon energy transition should be focused on coal resource areas. In these locations the selection and effect of transition tools are key to ensuring that China meets its carbon reduction goal. Due to the time window of clean coal utilization the pressure of local governments and the survival demands of local high energy consuming enterprises Shanxi Province chose hydrogen as its important transition tool. A path for developing hydrogen resources has been established through lobbying and corporative influence on local and provincial governments. Based on such policy guidance Shanxi has realized hydrogen applications in large-scale industrial parks regional public transport and the iron and steel industry. This paper distinguishes between the development strategies of gray and green hydrogen. It shows that hydrogen can be an effective development model for resource-based regions as it balances economic stability and energy transition.
Towards Green Hydrogen? - A Comparison of German and African Visions and Expectations in the Context of the H2Atlas-Africa Project
Sep 2023
Publication
Green hydrogen promises to be critical in achieving a sustainable and renewable energy transition. As green hydrogen is produced with renewables green hydrogen could become an energy storage medium of the future and even substitute the current unsustainable grey or blue hydrogen used in the industry. Bringing this transition into reality for instance in Germany there are visions to rapidly build hydrogen facilities in Africa and export the produced green hydrogen to Europe. One problem however is that these visions presumably conflict with the visions of actors within Africa. Therefore this study aims to provide an initial assessment of African stakeholders’ visions for future energy exports and renewable energy expectations. By comparing visions from Germany and Africa this assessment was conducted to identify differences in green energy and hydrogen visions that could lead to conflict and similarities that could be the basis for cooperation. The National Hydrogen Strategy outlines the German visions which clarifies that Germany will have to import green hydrogen to meet its green transition target. In this context of future energy export demand a partnership between German and African researchers on assessing green hydrogen potentials in Africa started. The African visions were explored by surveying the partners from different African countries working on the project. The results revealed that while both sides see the need for an immediate transition to renewable energy the African side is not envisioning the immediate export of green hydrogen. Based on the responses the partners are primarily concerned with improving the continent’s still deficient energy access for both the population and industry. Nevertheless this African perspective greatly emphasises cross-border cooperation where both sides can realise their visions. In the case of Germany that German investment could build infrastructure which would benefit the receiving African country or countries and open up the possibility for the envisioned green hydrogen export to Europe.
Battery and Hydrogen Energy Storage Control in a Smart Energy Network with Flexible Energy Demand Using Deep Reinforcement Learning
Sep 2023
Publication
Smart energy networks provide an effective means to accommodate high penetrations of variable renewable energy sources like solar and wind which are key for the deep decarbonisation of energy production. However given the variability of the renewables as well as the energy demand it is imperative to develop effective control and energy storage schemes to manage the variable energy generation and achieve desired system economics and environmental goals. In this paper we introduce a hybrid energy storage system composed of battery and hydrogen energy storage to handle the uncertainties related to electricity prices renewable energy production and consumption. We aim to improve renewable energy utilisation and minimise energy costs and carbon emissions while ensuring energy reliability and stability within the network. To achieve this we propose a multi-agent deep deterministic policy gradient approach which is a deep reinforcement learning-based control strategy to optimise the scheduling of the hybrid energy storage system and energy demand in real time. The proposed approach is model-free and does not require explicit knowledge and rigorous mathematical models of the smart energy network environment. Simulation results based on real-world data show that (i) integration and optimised operation of the hybrid energy storage system and energy demand reduce carbon emissions by 78.69% improve cost savings by 23.5% and improve renewable energy utilisation by over 13.2% compared to other baseline models; and (ii) the proposed algorithm outperforms the state-of-the-art self-learning algorithms like the deep-Q network.
Parameterization Proposal to Determine the Feasibility of Geographic Areas for the Green Hydrogen Industry under Socio-environmental and Technical Constraints in Chile
Oct 2023
Publication
Chile abundant in solar and wind energy resources presents significant potential for the production of green hydrogen a promising renewable energy vector. However realizing this potential requires an understanding of the most suitable locations for the installation of green hydrogen industries. This study proposes a quantitative methodology that identifies and ranks potential public lands for industrial use based on a range of technical parameters (such as solar and wind availability) and socio-environmental considerations (including land use restrictions and population density). The results reveal optimal locations that can facilitate informed sustainable decision-making for large-scale green hydrogen implementation in Chile. While this methodology does not replace project-specific technical or environmental impact studies it provides a flexible general classification to guide initial site selection. Notably this approach can be applied to other regions worldwide with abundant solar and wind resources such as Australia and Northern Africa promoting more effective and sustainable global decision-making for green hydrogen production.
Renewable Hydrogen Production Processes for the Off-Gas Valorization in Integrated Steelworks through Hydrogen Intensified Methane and Methanol Syntheses
Nov 2020
Publication
Within integrated steelmaking industries significant research efforts are devoted to the efficient use of resources and the reduction of CO2 emissions. Integrated steelworks consume a considerable quantity of raw materials and produce a high amount of by-products such as off-gases currently used for the internal production of heat steam or electricity. These off-gases can be further valorized as feedstock for methane and methanol syntheses but their hydrogen content is often inadequate to reach high conversions in synthesis processes. The addition of hydrogen is fundamental and a suitable hydrogen production process must be selected to obtain advantages in process economy and sustainability. This paper presents a comparative analysis of different hydrogen production processes from renewable energy namely polymer electrolyte membrane electrolysis solid oxide electrolyze cell electrolysis and biomass gasification. Aspen Plus® V11-based models were developed and simulations were conducted for sensitivity analyses to acquire useful information related to the process behavior. Advantages and disadvantages for each considered process were highlighted. In addition the integration of the analyzed hydrogen production methods with methane and methanol syntheses is analyzed through further Aspen Plus®-based simulations. The pros and cons of the different hydrogen production options coupled with methane and methanol syntheses included in steelmaking industries are analyzed
Impact on Canadian Residential End Use Appliances with the Introduction of Hydrogen into the Natural Gas Stream - An Application
Sep 2023
Publication
Canada’s commitment to be net-zero by 2050 combined with ATCO’s own Environmental Social and Governance goals has led ATCO to pursue hydrogen blending within the existing natural gas system to reduce CO2 emissions while continuing to provide safe reliable energy service to customers. Utilization of hydrogen in the distribution system is the least-cost alternative for decarbonizing the heating loads in jurisdictions like Alberta where harsh winter climates are encountered and low-carbon hydrogen production can be abundant. ATCO’s own Fort Saskatchewan Hydrogen Blending Project began blending 5% hydrogen by volume to over 2100 customers in the Fall of 2022 and plans to increase the blend rates to 20% hydrogen in 2023. Prior to blending ATCO worked together with DNV to examine the impact of hydrogen blended natural gas to twelve Canadian appliances: range/stove oven garage heater high and medium efficiency furnaces conventional and on demand hot water heaters barbeque clothes dryer radiant heater and two gas fireplaces. The tests were performed not only within the planned blend rates of 0-20% hydrogen but also to higher percentages to determine how much hydrogen can be blended into a system before appliance retrofits would be required. The testing was designed to get insights on safety-related combustion issues such as flash-back burner overheating flame detection and other performance parameters such as emissions and burner power. The experimental results indicate that the radiant heater is the most sensitive appliance for flashback observed at 30 vol% hydrogen in natural gas. At 50% hydrogen the range and the radiant burner of the barbeque tested were found to be sensitive to flashback. All other 9 appliances were found to be robust for flashback with no other short-term issues observed. This paper will detail the findings of ATCO and DNV’s appliance testing program including results on failure mechanisms and sensitivities for each appliance.
Carbon-Free Heat Production for High-Temperature Heating Systems
Oct 2023
Publication
The article presents a new carbon-free heat production technology for district heating which consists of a combined heat and power generation fuel cell (FC CHP) with CO2 capture and a two-stage cascade high-temperature heat pump (TCHHP). The FC generates heat and electricity the latter being used to drive the compressors of the TCHHP. During the winter period the water temperature achieved can occasionally be too low so it would be heated up with hydrogen gas boilers. The hydrogen would be produced by reforming natural gas synthetic methane or biogas. The results are presented with natural gas utilization—the ratio between the obtained heat flow transferred directly to the water for district heating and the input heat flow of natural gas. In the case of a return water temperature of 60 ◦C and district heating temperature of 85 ◦C the TCHHP whose heat source is groundwater achieves plant efficiency of 270.04% in relation to the higher heating value (HHV) and 241.74% in relation to the lower heating value (LHV) of natural gas. A case with a TCHHP whose heat source is low-temperature geothermal water achieves a plant efficiency of 361.36% in relation to the HHV and 323.49% in relation to the LHV
Nanomaterials: Paving the Way for the Hydrogen Energy Frontier
Jan 2024
Publication
This comprehensive review explores the transformative role of nanomaterials in advancing the frontier of hydrogen energy specifcally in the realms of storage production and transport. Focusing on key nanomaterials like metallic nanoparticles metal–organic frameworks carbon nanotubes and graphene the article delves into their unique properties. It scrutinizes the application of nanomaterials in hydrogen storage elucidating both challenges and advantages. The review meticulously evaluates diverse strategies employed to overcome limitations in traditional storage methods and highlights recent breakthroughs in nanomaterial-centric hydrogen storage. Additionally the article investigates the utilization of nanomaterials to enhance hydrogen production emphasizing their role as efcient nanocatalysts in boosting hydrogen fuel cell efciency. It provides a comprehensive overview of various nanocatalysts and their potential applications in fuel cells. The exploration extends to the realm of hydrogen transport and delivery specifcally in storage tanks and pipelines ofering insights into the nanomaterials investigated for this purpose and recent advancements in the feld. In conclusion the review underscores the immense potential of nanomaterials in propelling the hydrogen energy frontier. It emphasizes the imperative for continued research aimed at optimizing the properties and performance of existing nanomaterials while advocating for the development of novel nanomaterials with superior attributes for hydrogen storage production and transport. This article serves as a roadmap shedding light on the pivotal role nanomaterials can play in advancing the development of clean and sustainable hydrogen energy technologies.
Renewable Fuel Production and the Impact of Hydrogen Infrastructure - A Case Study of the Nordics
Apr 2024
Publication
Hard-to-electrify sectors will require renewable fuels to facilitate the green transition in the future. Therefore it is crucial to identify promising production locations while taking into account the local biomass resources variable renewable energy sources and the synergies between sectors. In this study investments and dispatch operations are optimised of a large catalogue of renewable fuel production technologies in the open-source software SpineOpt and this is soft-linked to the comprehensive energy system model Balmorel. We analyse future production pathways by comparing various levels of hydrogen infrastructure including large-scale hydrogen storage and assess system impacts. The results indicate that methanol may provide synergies in its multipurpose use as an early (2030–2040) shipping fuel and later as an aviation fuel through further refining if ammonia becomes more competitive (2050). We furthermore show that a hydrogen infrastructure increases the competitiveness of non-flexible hydrogen-based fuel production technologies. Offshore electrolysis hubs decrease energy system impacts in scenarios with 105 TWh of Nordic hydrogen export. However hydrogen export scenarios are much costlier compared to scenarios with no export unless a high hydrogen price is received. Finally we find that emission taxes in the range of 250–265 e/tCO2 will be necessary for renewable fuels to become competitive.
Literature Review of Hydrogen Energy Systems and Renewable Energy Sources
Nov 2023
Publication
The role of hydrogen as a clean energy source is a promising but also a contentious issue. The global energy production is currently characterized by an unprecedented shift to renewable energy sources (RES) and their technologies. However the local and environmental benefits of such RES-based technologies show a wide variety of technological maturity with a common mismatch to local RES stocks and actual utilization levels of RES exploitation. In this literature review the collected documents taken from the Scopus database using relevant keywords have been organized in homogeneous clusters and are accompanied by the registration of the relevant studies in the form of one figure and one table. In the second part of this review selected representations of typical hydrogen energy system (HES) installations in realistic in-field applications have been developed. Finally the main concerns challenges and future prospects of HES against a multi-parametric level of contributing determinants have been critically approached and creatively discussed. In addition key aspects and considerations of the HES-RES convergence are concluded.
Caveats of Green Hydrogen for Decarbonisation of Heating in Buildings
Oct 2023
Publication
Hydrogen (H2) has rapidly become a topic of great attention when discussing routes to net-zero carbon emissions. About 14% of CO2 emissions globally are directly associated with domestic heating in buildings. Replacing natural gas (NG) with H2 for heating has been highlighted as a rapid alternative for mitigating these emissions. To realise this not only the production challenges but also potential obstacles in the transmission/distribution and combustion of H2 must be technically identified and discussed. This review in addition to delineating the challenges of H2 in NG grid pipelines and H2 combustion also collates the results of the state-of-the-art technologies in H2-based heating systems. We conclude that the sustainability of water and renewable electricity resources strongly depends on sizing siting service life of electrolysis plants and post-electrolysis water disposal plans. 100% H2 in pipelines requires major infrastructure upgrades including production transmission pressurereduction stations distribution and boiler rooms. H2 leakage instigates more environmental risks than economic ones. With optimised boilers burning H2 could reduce GHG emissions and obtain an appropriate heating efficiency; more data from boiler manufacturers must be provided. Overall green H2 is not the only solution to decarbonise heating in buildings and it should be pursued abreast of other heating technologies.
The European Hydrogen Policy Landscape
Apr 2024
Publication
This report aims to summarise the status of the European hydrogen policies and standards landscape. It is based on the information available at the European Hydrogen Observatory (EHO) platform the leading source of data and information on hydrogen in Europe (EU27 EFTA and the UK) providing an overview of the European and national policies legislations strategies and codes and standards which impact the deployment of hydrogen technologies and infrastructures. The EHO database covers a total of 29 EU policies and legislations that directly or indirectly affect the development and deployment of hydrogen technologies. To achieve its net zero ambitions the EU started with cross-cutting strategies such as the EU Green Deal and the EU Hydrogen Strategy setting forward roadmaps and targets that are to be achieved in the near future. As a next step the EU has developed legislations such as those bundled in the Fit for 55 package to meet the targets they have put forward. The implemented legislations including funding vehicles and initiatives have an impact on the whole value chain of hydrogen including production transport storage and distribution and end-uses. At national level as of July 2023 63% of the European countries have successfully published their national strategies in the hydrogen sector while 6% of the countries are currently in the draft stage. Several European countries have strategically incorporated quantitative indicators within their national strategies outlining their targets and estimates across the hydrogen value chain. This deliberate approach reflects a commitment to providing clear and measurable goals within their hydrogen strategies. A target often used in the national strategies is on electrolyser capacity as an effort to enhance the domestic renewable hydrogen production. Germany took the lead with an ambitious goal of achieving 10 GW by 2030 followed by France (6.5 GW) and Denmark (4 - 6 GW). Other targets that some of the countries use in their strategies are on the number of hydrogen refuelling stations fuel cell electric vehicles and total (renewable) hydrogen demand. A few countries also have targets on renewable hydrogen uptake in industry and hydrogen injection limit in the transmission grid. To monitor the policies and legislation that are adopted on a national level across the hydrogen value chain a survey was launched with national experts which was validated by Hydrogen Europe. In total 28 European countries have participated to the survey. On production the survey revealed that 61% of country specialists report that their country provides support for capital expenditure (CAPEX) in the development of renewable or low-carbon hydrogen production plants. Moreover 7 countries also provide support for operational expenditure (OPEX). Furthermore 8 countries have instituted official 6 permitting guidelines for hydrogen production projects while 5 countries have enacted a legal act or established an agency serving as a single point of contact for hydrogen project developers. For transmission only two countries reported to provide support schemes for hydrogen injection. Several countries have policies in place that clearly define the hydrogen limit in their transmission grid for now and in the future ranging from 0.02% up to 15% while a few countries define within their policies the operation of hydrogen storage facilities. On end-use the majority of countries totalling 71% reported to have implemented support schemes aimed at promoting the adoption of hydrogen in the mobility sector. Purchase subsidies stand out as the predominant form of support for fuel cell electric vehicles (FCEVs) with implementation observed in 17 countries. In the context of support schemes for stationary fuel applications for heating or power generation only two countries have adopted such measures. A slightly larger group of four countries do provide support for the deployment of residential and commercial heating systems utilizing hydrogen. For hydrogen end-use in industry a total of 9 countries reported to provide support schemes with a major focus on ammonia production (8) and the chemicals industry (7). On the topic of technology manufacturing 7 countries have reported to have support schemes of which grants emerge as the mainly used method (4). Exploring the latest advancements into European codes and standards relevant to the deployment of hydrogen technologies and infrastructures a total of 11 standards have been revised and developed between January 2022 and September 2023. This includes standards covering the following areas: 6 for fuel cell technologies 2 for gas cylinders 2 for road vehicles and 1 for hydrogen refuelling. Moreover 5 standards were published since September 2023 which will be added to the EHO database in its next update. This includes ISO/TS 19870:2023 which sets a methodology for determining the greenhouse gas emissions associated with the production conditioning and transport of hydrogen to consumption gate. This landmark standard which was unveiled at COP28 aims to act as a foundation for harmonization safety interoperability and sustainability across the hydrogen value chain.
Hydrogen in Aviation: A Simulation of Demand, Price Dynamics, and CO2 Emission Reduction Potentials
Mar 2024
Publication
Aviation contributes to anthropogenic climate change by emitting both carbon dioxide (CO2) and non-CO2 emissions through the combustion of fossil fuels. One approach to reduce the climate impact of aviation is the use of hydrogen as an alternative fuel. Two distinct technological options are presently under consideration for the implementation of hydrogen in aviation: hydrogen fuel cell architectures and the direct combustion of hydrogen. In this study a hydrogen demand model is developed that considers anticipated advancements in liquid hydrogen aircraft technologies forecasted aviation demand and aircraft startup and retirement cycles. The analysis indicates that global demand for liquid hydrogen in aviation could potentially reach 17 million tons by 2050 leading to a 9% reduction in CO2 emissions from global aviation. Thus the total potential of hydrogen in aviation extends beyond this considering that the total market share of hydrogen aircraft on suitable routes in the model is projected to be only 27% in 2050 due to aircraft retirement cycles. Additionally it is shown that achieving the potential demand for hydrogen in aviation depends on specific market prices. With anticipated declines in current production costs hydrogen fuel costs would need to reach about 70 EUR/MWh by 2050 to fulfill full demand in aviation assuming biofuels provide the cheapest option for decarbonization alongside hydrogen. If e-fuels are the sole option for decarbonization alongside hydrogen which is the more probable scenario the entire hydrogen demand potential in aviation would be satisfied according to this study’s estimates at significantly higher hydrogen prices approximately 180 EUR/MWh.
Preliminary Study for the Commercialization of a Electrochemical Hydrogen Compressor
Mar 2023
Publication
A global energy shift to a carbon‐neutral society requires clean energy. Hydrogen can accelerate the process of expanding clean and renewable energy sources. However conventional hydrogen compression and storage technology still suffers from inefficiencies high costs and safety concerns. An electrochemical hydrogen compressor (EHC) is a device similar in structure to a water electrolyzer. Its most significant advantage is that it can accomplish hydrogen separation and compression at the same time. With no mechanical motion and low energy consumption the EHC is the key to future hydrogen compression and purification technology breakthroughs. In this study the compression performance efficiency and other related parameters of EHC are investigated through experiments and simulation calculations. The experimental results show that under the same experimental conditions increasing the supply voltage and the pressure in the anode chamber can improve the reaction rate of EHC and balance the pressure difference between the cathode and anode. The presence of residual air in the anode can impede the interaction between hydrogen and the catalyst as well as the proton exchange membrane (PEM) resulting in a decrease in performance. In addition it was found that a single EHC has a better compression ratio and reaction rate than a double EHC. The experimental results were compatible with the theoretical calculations within less than a 7% deviation. Finally the conditions required to reach commercialization were evaluated using the theoretical model.
Decarbonising the Refinery Sector: A Socio-technical Analysis of Advanced Biofuels, Green Hydrogen and Carbon Capture and Storage Developments in Sweden
Nov 2021
Publication
The oil refinery industry is one of the major energy users and responsible for a large proportion of greenhouse gas (GHG) emissions. This sector is facing multiple sustainability-related transformation pressures forcing the industry to adapt to changing market conditions. The transition to a low-carbon economy will require oil refineries to adopt decarbonisation technologies like advanced biofuels green hydrogen and carbon capture and storage (CCS). However the development and implementation of these technologies is not a straightforward process and may be inhibited by lock-in and path dependency. This paper draws on expert interviews and combines the Technological Innovation Systems (TIS) and Multi-level Perspective (MLP) frameworks to examining the niche level development of three emerging technologies in the context of deep decarbonisation of refinery. This research finds that the development of the three decarbonisation technologies shares some of the challenges and opportunities and exhibits technology interdependency to some extent. Among the three TISs advanced biofuel is the most mature in terms of knowledge base actor-network legislation framework and market function. Green hydrogen and CCS encounter stronger momentum than before and can benefit from possible synergies across various sectors. However the analysis also reveals the lack of market formation mainly due to the lack of policy instruments for niche markets. Here policy recommendations for accelerating deep decarbonisation of the oil refinery industry are discussed. Finally we contribute to the sustainability transitions literature by exploring the dynamics of emerging TISs for industrial decarbonisation.
Recent Advances in Sustainable Hydrogen Production from Microalgae: Mechanisms, Challenges, and Future Perspectives
Jan 2024
Publication
The depletion of fossil fuel reserves has resulted from their application in the industrial and energy sectors. As a result substantial efforts have been dedicated to fostering the shift from fossil fuels to renewable energy sources via technological advancements in industrial processes. Microalgae can be used to produce biofuels such as biodiesel hydrogen and bioethanol. Microalgae are particularly suitable for hydrogen production due to their rapid growth rate ability to thrive in diverse habitats ability to resolve conflicts between fuel and food pro duction and capacity to capture and utilize atmospheric carbon dioxide. Therefore microalgae-based bio hydrogen production has attracted significant attention as a clean and sustainable fuel to achieve carbon neutrality and sustainability in nature. To this end the review paper emphasizes recent information related to microalgae-based biohydrogen production mechanisms of sustainable hydrogen production factors affecting biohydrogen production by microalgae bioreactor design and hydrogen production advanced strategies to improve efficiency of biohydrogen production by microalgae along with bottlenecks and perspectives to over come the challenges. This review aims to collate advances and new knowledge emerged in recent years for microalgae-based biohydrogen production and promote the adoption of biohydrogen as an alternative to con ventional hydrocarbon biofuels thereby expediting the carbon neutrality target that is most advantageous to the environment.
Electrolyzer Array Alternate Control Strategy Considering Wind Power Prediction
Aug 2022
Publication
Non grid connected wind power hydrogen production technology is of great significance for the large-scale comprehensive utilization of hydrogen energy and accelerating the development of clean energy. In this paper an electrolyzer power allocation and alternate control method for non grid connected wind power hydrogen production is proposed and the optimized control strategy are combined to predict the maximum wind power of certain time interval. While retaining the required data characteristics the instantaneous fluctuation of some wind power data is eliminated which provides a reliable basis for power distribution in the alternation control strategy of electrolyzer array. The case simulation verifies the effectiveness of the electrolyzer array control principle and the prediction of the maximum wind power. While ensuring the absorption effect and hydrogen production rate the service life and operation safety of the electrolyzer array are effectively improved by balancing the working state of each electrolyzer.
Performance and Failure Analysis of a Retrofitted Cessna Aircraft with a Fuel Cell Power System Fuelled with Liquid Hydrogen
Jan 2022
Publication
Proton-Exchange Membrane-Fuel Cells (PEM-FC) are regarded as one of the prime candidates to provide emissions-free electricity for propulsion systems of aircraft. Here a turbocharged Fuel Cell Power System (FCPS) powered with liquid H2 (LH2) is designed and modelled to provide a primary power source in retrofitted Cessna 208 Caravan aircraft. The proposed FCPS comprises multiple PEM-FCs assembled in stacks two single-stage turbochargers to mitigate the variation of the ambient pressure with altitude two preheaters two humidifiers and two combustors. Interlinked component sub-models are constructed in MATLAB and referenced to commercially available equipment. The FCPS model is used to simulate steady-state responses in a proposed 1.5 h (∼350 km) mission flight determining the overall efficiency of the FCPS at 43% and hydrogen consumption of ∼28 kg/h. The multi-stack FCPS is modelled applying parallel fluidic and electrical architectures analysing two power-sharing methods: equally distributed and daisy-chaining. The designed LH2-FCPS is then proposed as a power system to a retrofitted Cessna 208 Caravan and with this example analysed for the probability of failure occurrence. The results demonstrate that the proposed “dual redundant” FCPS can reach failure rates comparable to commercial jet engines with a rate below 1.6 failures per million hours.
No more items...