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The development of a hydrogen energy-based society is becoming the solution for more and more countries. Fuel cell electric vehicles are the best carriers for developing a hydrogen energy-based society. The current research on hydrogen leakage and the diffusion of fuel cell electric vehicles has been sufficient. However, the study of hydrogen safet...
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... assess the effect of the jet diameter on the diffusion of hydrogen, France (Atomic Energy and Alternative Energy Commission) studied the effect of the hy volume (test 1 and test 2) and the injection port caliber (test 3 and test 4) [27] on drogen concentration distribution. In order to evaluate the diffusion of the hydrog centration, a confined space was constructed with 30 sensor matrices; the exper enclosure scheme is shown in Figure 2. The research parameter combinations are shown in Table 2. The test results of test 1 and test 2 showed that, under the same conditions, the different leakage amounts will also affect the hydrogen diffusion. ...Similar publications
The number of internal combustion vehicles annually registered in Germany continues to outstrip that of electric cars, which will be continuingly dependent on fuel supplies. Those ambitious goals are disclosed by the European Green Deal, which not only calls for new technical approaches but also for greenhouse gas-neutral transition technologies. F...
The introduction of new Euro exhaust emission standards and CO2 limits has forced carmakers to implement alternative hybrid and electric powertrains. We are observing a dynamic advancement of this sector. The authors’ primary motivation was to perform a series of measurements of the exhaust emissions and fuel mileages from vehicles fitted with hybr...
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... While there are some excellent review articles available in this field [40,53,54], there is still a lack of a macro-level overview of the knowledge structure in this area. The current review articles on hydrogen safety mainly employ research methods that analyze the behavior of hydrogen leakage [55,56], diffusion [40,54,57], combustion [58,59], and explosion [40,60], as well as the thermodynamic mechanisms of hydrogen [61]. At the same time, taking into account current research trends and unresolved challenges, a forecast for the future development in the upcoming period is taken [53,62]. ...
This paper primarily revolves around the safety of hydrogen energy, utilizing bibliometric methods for visual analysis and offering insights into future research directions. A total of 8283 research papers focusing on hydrogen safety were analyzed in the past thirty years from the period of 1992 to 2022. The analysis covered diverse aspects, including the countries of publication, affiliations of authors, frequently cited journals, research hotspots, keywords, and future trends. The findings of this research indicate a growing prominence of studies related to hydrogen safety. Among the top 10 countries with the highest number of publications, China ranks first with 2414 research papers. Among the Total Link Strength (TLS) indicator, the United States, Germany, and China rank first, second, and third, indicating that they have extensive collaborative experiences internationally. The International Journal of Hydrogen Energy stands out with the highest publication count, totaling 931 articles. The research hotspots in the early, middle, and later stages have focused on hydrogen storage safety, hydrogen combustion and explosion safety, hydrogen self-ignition (including flame propagation), and hydrogen embrittlement, respectively. These trends suggest a continuous progression in understanding and addressing safety aspects in the field of hydrogen research. However, the understanding of mechanisms of hydrogen autoignition is still limited. There is an urgent need to further strengthen research on prevention and control measures related to hydrogen self-ignition. Furthermore, researchers also need focus on both quantity and quality, enhance international cooperation, and facilitate cross-disciplinary advancements in hydrogen safety.
... Various factors impact the hydrogen dispersion behaviour in an enclosed space, such as release pressure, leakage flow rate [49], leakage diameter [50], ventilation conditions, direction of leakage, and obstacles in the space [51,52]. To achieve the research objective, different leakage diameters and directions were included in the scenarios. ...
Adopting proton exchange membrane fuel cells fuelled by hydrogen presents a promising solution for the shipping industry’s deep decarbonisation. However, the potential safety risks associated with hydrogen leakage pose a significant challenge to the development of hydrogen-powered ships. This study examines the safe design principles and leakage risks of the hydrogen gas supply system of China’s first newbuilt hydrogen-powered ship. This study utilises the computational fluid dynamics tool FLACS to analyse the hydrogen dispersion behaviour and concentration distributions in the hydrogen fuel cell room based on the ship’s parameters. This study predicts the flammable gas cloud and time points when gas monitoring points first reach the hydrogen volume concentrations of 0.8% and 1.6% in various leakage scenarios, including four different diameters (1, 3, 5, and 10 mm) and five different directions. This study’s findings indicate that smaller hydrogen pipeline diameters contribute to increased hydrogen safety. Specifically, in the hydrogen fuel cell room, a single-point leakage in a hydrogen pipeline with an inner diameter not exceeding 3 mm eliminates the possibility of flammable gas cloud explosions. Following a 10 mm leakage diameter, the hydrogen concentration in nearly all room positions reaches 4.0% within 6 s of leakage. While the leakage diameter does not impact the location of the monitoring point that first activates the hydrogen leak alarm and triggers an emergency hydrogen supply shutdown, the presence of obstructions near hydrogen detectors and the leakage direction can affect it. These insights provide guidance on the optimal locations for hydrogen detectors in the fuel cell room and the pipeline diameters on hydrogen gas supply systems, which can facilitate the safe design of hydrogen-powered ships.
... A significant amount of greenhouse gases is emitted from the transportation sector; therefore, the application of electric vehicles can save the environment [20][21][22][23][24]. Compared to battery-powered electric vehicles, fuel cell-based electric vehicles are more attractive due to the ease of charging and the long lifetime. The safety of hydrogen fuel cells in electric vehicles included the diffusion and oxidation behaviour of hydrogen fuel [25]. The risk of a hydrogen leak or combustion of fuel cells in electric vehicles is manageable as ...
... A significant amount of greenhouse gases is emitted from the transportation sector; therefore, the application of electric vehicles can save the environment [20][21][22][23][24]. Compared to battery-powered electric vehicles, fuel cell-based electric vehicles are more attractive due to the ease of charging and the long lifetime. The safety of hydrogen fuel cells in electric vehicles included the diffusion and oxidation behaviour of hydrogen fuel [25]. The risk of a hydrogen leak or combustion of fuel cells in electric vehicles is manageable as long as proper precautions are followed. ...
The rapid growth in fossil fuels has resulted in climate change that needs to be controlled in the near future. Several methods have been proposed to control climate change, including the development of efficient energy conversion devices. Fuel cells are environmentally friendly energy conversion devices that can be fuelled by green hydrogen, with only water as a by-product, or by using different biofuels such as biomass in wastewater, urea in wastewater, biogas from municipal and agricultural wastes, syngas from agriculture wastes, and waste carbon. This editorial discusses the fundamentals of the operation of the fuel cell, and their application in various sectors such as residential, transportation, and power generation.
The use of hydrogen as an energy carrier within the scope of the decarbonisation of the world’s energy production and utilisation is seen by many as an integral part of this endeavour. However, the discussion around hydrogen technologies often lacks some perspective on the currently available technologies, their Technology Readiness Level (TRL), scope of application, and important performance parameters, such as energy density or conversion efficiency. This makes it difficult for the policy makers and investors to evaluate the technologies that are most promising. The present study aims to provide help in this respect by assessing the available technologies in which hydrogen is used as an energy carrier, including its main challenges, needs and opportunities in a scenario in which fossil fuels still dominate global energy sources but in which renewables are expected to assume a progressively vital role in the future. The production of green hydrogen using water electrolysis technologies is described in detail. Various methods of hydrogen storage are referred, including underground storage, physical storage, and material-based storage. Hydrogen transportation technologies are examined, taking into account different storage methods, volume requirements, and transportation distances. Lastly, an assessment of well-known technologies for harnessing energy from hydrogen is undertaken, including gas turbines, reciprocating internal combustion engines, and fuel cells. It seems that the many of the technologies assessed have already achieved a satisfactory degree of development, such as several solutions for high-pressure hydrogen storage, while others still require some maturation, such as the still limited life and/or excessive cost of the various fuel cell technologies, or the suitable operation of gas turbines and reciprocating internal combustion engines operating with hydrogen. Costs below 200 USD/kWproduced, lives above 50 kh, and conversion efficiencies approaching 80% are being aimed at green hydrogen production or electricity production from hydrogen fuel cells. Nonetheless, notable advances have been achieved in these technologies in recent years. For instance, electrolysis with solid oxide cells may now sometimes reach up to 85% efficiency although with a life still in the range of 20 kh. Conversely, proton exchange membrane fuel cells (PEMFCs) working as electrolysers are able to sometimes achieve a life in the range of 80 kh with efficiencies up to 68%. Regarding electricity production from hydrogen, the maximum efficiencies are slightly lower (72% and 55%, respectively). The combination of the energy losses due to hydrogen production, compression, storage and electricity production yields overall efficiencies that could be as low as 25%, although smart applications, such as those that can use available process or waste heat, could substantially improve the overall energy efficiency figures. Despite the challenges, the foreseeable future seems to hold significant potential for hydrogen as a clean energy carrier, as the demand for hydrogen continues to grow, particularly in transportation, building heating, and power generation, new business prospects emerge. However, this should be done with careful regard to the fact that many of these technologies still need to increase their technological readiness level before they become viable options. For this, an emphasis needs to be put on research, innovation, and collaboration among industry, academia, and policymakers to unlock the full potential of hydrogen as an energy vector in the sustainable economy.
Smart energy networks including renewables and energy storage systems are a promising technology for improving the sustainability of residential districts and private mobility. In this work, a smart energy network is analyzed, based on photovoltaic panels, electric energy storage systems, heat pumps and electric vehicles. The system consists of a fully electric residential district, where air-to-air heat pumps are used for space heating and cooling and air-to-water heat pumps provide domestic hot water; a photovoltaic field meets the power load of the residential district, including charging stations for electric vehicles. A district electric energy storage system is included for balancing power supply and demand: two storage technologies are considered and compared in this work: a lithium-ion battery and a reversible solid oxide fuel cell. These systems are modelled and dynamically simulated in Transient Systems Simulation Program (TRNSYS) 18. A case study is discussed, where the proposed systems exhibit promising results in terms of primary energy saving: for example, the renewable energy matches almost 74–77% of the district primary energy demand for the analyzed smart energy districts. Moreover, both the proposed systems achieve very profitable results with a payback period of 3.5–4.4 years. Both the analyzed layouts achieve very similar results.
This study aimed to improve the efficiency of government regulations and promote the market applications of electric buses. Based on evolutionary game theory, with electric bus manufacturers, passenger transport enterprises, and the government as the evolutionary game subjects, a tripartite evolutionary game model of production-use management is established. An equilibrium stabilization strategy was derived through game equilibrium and evolutionary stability analysis, and the influence of changes in key variables on the choice of promotion behavior of decision subjects was quantitatively analyzed. The results of the empirical analysis showed that when the government adjusts the policy subsidy between 6–10, the changes in the sensitivity of manufacturers and passenger transport enterprises are relatively high, and the decisions of both sides tend to be 1; if the government penalty is adjusted to 4.8–6.8, the government strictly regulates the promotion of electric bus policy, and the manufacturers and passenger transport enterprises choose to actively participate in the promotion strategy, effectively constraining the decision-making behavior of all parties, which verifies the validity and consistency of the model analysis conclusions. The conclusions will provide theoretical reference for the formulation of government regulatory policies and the development of low-carbon transportation.
