Chinese Taipei
Decrease in Hydrogen Embrittlement Susceptibility of 10B21 Screws by Bake Aging
Aug 2016
Publication
The effects of baking on the mechanical properties and fracture characteristics of low-carbon boron (10B21) steel screws were investigated. Fracture torque tests and hydrogen content analysis were performed on baked screws to evaluate hydrogen embrittlement (HE) susceptibility. The diffusible hydrogen content within 10B21 steel dominated the fracture behavior of the screws. The fracture torque of 10B21 screws baked for a long duration was affected by released hydrogen. Secondary ion mass spectroscopy (SIMS) result showed that hydrogen content decreased with increasing baking duration and thus the HE susceptibility of 10B21 screws improved. Diffusible hydrogen promoted crack propagation in high-stress region. The HE of 10B21 screws can be prevented by long-duration baking.
Water Photo-Electrooxidation Using Mats of TiO2 Nanorods, Surface Sensitized by a Metal–Organic Framework of Nickel and 1,2-Benzene Dicarboxylic Acid
Apr 2021
Publication
Photoanodes comprising a transparent glass substrate coated with a thin conductive film of fluorine-doped tin oxide (FTO) and a thin layer of a photoactive phase have been fabricated and tested with regard to the photo-electro-oxidation of water into molecular oxygen. The photoactive layer was made of a mat of TiO2 nanorods (TDNRs) of micrometric thickness. Individual nanorods were successfully photosensitized with nanoparticles of a metal–organic framework (MOF) of nickel and 12-benzene dicarboxylic acid (BDCA). Detailed microstructural information was obtained from SEM and TEM analysis. The chemical composition of the active layer was determined by XRD XPS and FTIR analysis. Optical properties were determined by UV–Vis spectroscopy. The water photooxidation activity was evaluated by linear sweep voltammetry and the robustness was assessed by chrono-amperometry. The OER (oxygen evolution reaction) photo-activity of these photoelectrodes was found to be directly related to the amount of MOF deposited on the TiO2 nanorods and was therefore maximized by adjusting the MOF content. The microscopic reaction mechanism which controls the photoactivity of these photoelectrodes was analyzed by photo-electrochemical impedance spectroscopy. Microscopic rate parameters are reported. These results contribute to the development and characterization of MOF-sensitized OER photoanodes.
Effect of Low-Temperature Sensitization on Hydrogen Embrittlement of 301 Stainless Steel
Feb 2017
Publication
The effect of metastable austenite on the hydrogen embrittlement (HE) of cold-rolled (30% reduction in thickness) 301 stainless steel (SS) was investigated. Cold-rolled (CR) specimens were hydrogen-charged in an autoclave at 300 or 450 °C under a pressure of 10 MPa for 160 h before tensile tests. Both ordinary and notched tensile tests were performed in air to measure the tensile properties of the non-charged and charged specimens. The results indicated that cold rolling caused the transformation of austenite into α′ and ε-martensite in the 301 SS. Aging at 450 °C enhanced the precipitation of M23C6 carbides G and σ phases in the cold-rolled specimen. In addition the formation of α′ martensite and M23C6 carbides along the grain boundaries increased the HE susceptibility and low-temperature sensitization of the 450 °C-aged 301 SS. In contrast the grain boundary α′-martensite and M23C6 carbides were not observed in the as-rolled and 300 °C-aged specimens
Recent Developments in Carbon-Based Nanocomposites for Fuel Cell Applications: A Review
Jan 2022
Publication
Carbon-based nanocomposites have developed as the most promising and emerging materials in nanoscience and technology during the last several years. They are microscopic materials that range in size from 1 to 100 nanometers. They may be distinguished from bulk materials by their size shape increased surface-to-volume ratio and unique physical and chemical characteristics. Carbon nanocomposite matrixes are often created by combining more than two distinct solid phase types. The nanocomposites that were constructed exhibit unique properties such as significantly enhanced toughness mechanical strength and thermal/electrochemical conductivity. As a result of these advantages nanocomposites have been used in a variety of applications including catalysts electrochemical sensors biosensors and energy storage devices among others. This study focuses on the usage of several forms of carbon nanomaterials such as carbon aerogels carbon nanofibers graphene carbon nanotubes and fullerenes in the development of hydrogen fuel cells. These fuel cells have been successfully employed in numerous commercial sectors in recent years notably in the car industry due to their cost-effectiveness eco-friendliness and long-cyclic durability. Further; we discuss the principles reaction mechanisms and cyclic stability of the fuel cells and also new strategies and future challenges related to the development of viable fuel cells.
The Influence of the Hydrogen Supply Modes on a Hydrogen Refueling Station
Apr 2020
Publication
Setting up and operating a hydrogen refueling station is a critical part of current drive for fuel cell vehicles. In setting up a hydrogen refueling station (HRS) the investor concerns of the capacity of HRS the quality of hydrogen the capital requirement of the station and the modes of hydrogen supply; interestingly the supply modes of hydrogen further influences the safety of the station the cost of hydrogen the energy consumption of supply and the area of hydrogen supply section in a station. Hydrogen can be supplied to a HRS by the procurement of the merchant hydrogen from a central source with the central hydrogen supply mode (CHSM) or by an onsite production of hydrogen in the distributed hydrogen supply mode (DHSM). In this presentation the above factors are evaluated with respect to these two supply modes of hydrogen. It is concluded that the lower hydrogen cost and the smaller site area as well as the safer aspect of the public concern of safety can be realized with the choice of the distributed hydrogen supply mode by an onsite hydrogen production from methanol.
Design and Dynamics Simulations of Small Scale Solid Oxide Fuel Cell Trigeneration System
Dec 2018
Publication
This paper presents the design of a solid oxide fuel cell (SOFC) tri-generation system that consists of an SOFC-combined heat and power subsystem an adsorption refrigeration subsystem and coupling devices between the two subsystems. Whereas typical extant designs use absorption techniques the proposed design employs adsorption refrigeration. In this paper the dynamics of adsorption refrigeration are reported in detail to evaluate the feasibility of the tri-generation system design. The design of the coupling devices and instrumentation strategies of the overall system are discussed in detail. Simulation results indicate that the proposed SOFC trigeneration system can output 4.35 kW of electrical power 2.448 kW of exhaust heat power and 1.348 kW of cooling power. The energy efficiency is 64.9% and the coefficient of performance of the refrigeration is 0.32. Varying the electrical output power results in the variation of exhaust heat power but not the cooling power; varying the cooling power affects the exhaust heat power but not the electrical power. These favorable features can be attributed to the proposed heat exchange sequence and active temperature controls of the system.
Simulations of Hydrogen Production by Methanol Steam Reforming
Jan 2019
Publication
Methanol is regarded as an important feedstock for hydrogen production due to its high energy density and superior transportability. A tubular packed-bed reactor performing the methanol steam reforming (MSR) process was modeled by adopting computational fluid dynamics (CFD) software to analyze its performance. Kinetic parameters of the reactions were adjusted according to the literatures and our previous experimental results. The methanol conversion the hydrogen production rate and the CO concentration in the produced mixture were evaluated by considering different levels of the length and temperature of the catalyst bed the steam-to-carbon ratio and the space velocity of the feedstocks. Moreover the correlation between the dimensionless parameter Damköhler number and the methanol conversion was also investigated.
Hydrogen Scooter Testing and Verification Program
Nov 2012
Publication
Taiwan stands out globally in the manufacture of scooters. If fuel cell technology could be applied to the scooter Taiwan could gain an advantage in the trend for commercial applications for fct. In 2011 The Bureau of Standards Metrology and Inspection proposed this project “the Demonstration of Hydrogen Fuel Cell Scooters.” Thirty rental fuel cell scooters are to run a long distance. Evaluation during everyday use of the cells performance will be made and reported by the riders. All the evaluations will be put into consideration of future adjustments. The project is to map out a practice route in Taipei and set up a control center to follow progress. The data gathered from the practice project will help examine the performance of fuel cell scooters contributing to the creation of legal drafts and future standards. The Taiwan fuel cell industry chain is complete and the industry possesses the ability to produce key components. Thus it is a potential market in Taiwan. A review of fuel cell development conditions in Taiwan shows that the fuel cell scooters is a niche industry owing to the strength of this technology.
Improvement in Hydrogen Production with Plasma Reformer System
Jun 2016
Publication
In our previous studies of a plasma reformer system the effects of temperature of the reactants and input voltage have not been considered. In the present investigation the plasma reformer system has been modified to study the influence of the reactants’ temperature and input voltage on hydrogen production experimentally. The plasma reformer system includes a supersonic atomizer a plasma generator and a controlling device. In the experiment the operating parameters include the temperature of the reactants and the input voltage. The temperature of the reactants varies from 25 °C to 50 °C and the input voltage ranges from 12.5 V to 14.5 V. Results show that the increase in temperature of the reactants and input voltage will improve the production of hydrogen. In addition the improvement of heating on the reactants shows significant influence on hydrogen production.
Graphene Oxide @ Nickel Phosphate Nanocomposites for Photocatalytic Hydrogen Production
Mar 2021
Publication
The graphene oxide @nickel phosphate (GO:NPO) nanocomposites (NCs) are prepared by using a one-pot in-situ solar energy assisted method by varying GO:NPO ratio i.e. 0.00 0.25 0.50 0.75 1.00 1.25 1.50 and 2.00 without adding any surfactant or a structure-directing reagent. As produced GO:NPO nanosheets exhibited an improved photocatalytic activity due to the spatial seperation of charge carriers through interface where photoinduced electrons transferred from NiPO4 to the GO sheets without charge-recombination. Out of the series the system 1.00 GO:NPO NC show the optimum hydrogen production activity (15.37 μmol H2 h−1) towards water splitting under the visible light irradiation. The electronic environment of the nanocomposite GO-NiO6/NiO4-PO4 elucidated in the light of advance experimental analyses and theoretical DFT spin density calculations. Structural advanmcement of composites are well correlated with their hydrogen production activity.
Power-to-fuels Via Solid-oxide Electrolyzer: Operating Window and Techno-economics
May 2019
Publication
Power-to-fuel systems via solid-oxide electrolysis are promising for storing excess renewable electricity by efficient electrolysis of steam (or co-electrolysis of steam and CO2) into hydrogen (or syngas) which can be further converted into synthetic fuels with plant-wise thermal integration. Electrolysis stack performance and durability determine the system design performance and long-term operating strategy; thus solid-oxide electrolyzer based power-to-fuels were investigated from the stack to system levels. At the stack level the data from a 6000-h stack testing under laboratory isothermal conditions were used to calibrate a quasi-2D model which enables to predict practical isothermal stack performance with reasonable accuracy. Feasible stack operating windows meeting various design specifications (e.g. specific syngas composition) were further generated to support the selection of operating points. At the system level with the chosen similar stack operating points various power-to-fuel systems including power-to-hydrogen power-to-methane power-to-methanol (dimethyl ether) and power-to-gasoline were compared techno-economically considering system-level heat integration. Several operating strategies of the stack were compared to address the increase in stack temperature due to degradation. The modeling results show that the system efficiency for producing H2 methane methanol/dimethyl ether and gasoline decreases sequentially from 94% (power-to-H2) to 64% (power-to-gasoline) based on a higher heating value. Co-electrolysis which allows better heat integration can improve the efficiency of the systems with less exothermic fuel-synthesis processes (e.g. methanol/dimethyl ether) but offers limited advantages for power-to-methane and power-to-gasoline systems. In a likely future scenario where the growing amount of electricity from renewable sources results in increasing periods of a negative electricity price solid oxide electrolyser based power-to-fuel systems are highly suitable for levelling the price fluctuations in an economic way.
Electrosynthesized Ni-P Nanospheres with High Activity and Selectivity Towards Photoelectrochemical Plastics Reforming
May 2021
Publication
Photoelectrochemical reforming of plastic waste offers an environmentally-benign and sustainable route for hydrogen generation. Nonetheless little attention was paid to develop electrocatalysts that can efficiently and selectively catalyze oxidative transformation of valueless plastic wastes into valued chemicals. Herein we report on facile electrosynthesis of nickel-phosphorus nanospheres (nanoNi-P) and their versatility in catalyzing hydrogen generation water oxidation and reforming of polyethylene terephthalate (PET). Notably composite of nanoNi-P with carbon nanotubes (CNT/nanoNi-P) requires −180 mV overpotential to drive hydrogen generation at -100 mA cm−2. Besides CV-activated nanoNi-P (nanoNi-P(CV)) was shown to be capable of reforming PET into formate with high selectivity (Faradic efficiency= ∼100 %). Efficient and selective generation of hydrogen and formate from PET reforming is realized utilizing an Earth-abundant photoelectrochemical platform based on nanoNi-P(CV)-modified TiO2 nanorods photoanode and CNT/nanoNi-P cathode. This work paves a path for developing artificial leaf for simultaneous environmental mitigation and photosynthesis of renewable fuels and valued chemicals.
Energy, Exergy, and Environmental Analyses of Renewable Hydrogen Production Through Plasma Gasification of Microalgal Biomass
Feb 2021
Publication
In this study an energy exergy and environmental (3E) analyses of a plasma-assisted hydrogen production process from microalgae is investigated. Four different microalgal biomass fuels namely raw microalgae (RM) and three torrefied microalgal fuels (TM200 TM250 and TM300) are used as the feedstock for steam plasma gasification to generate syngas and hydrogen. The effects of steam-tobiomass (S/B) ratio on the syngas and hydrogen yields and energy and exergy efficiencies of plasma gasification (hEn;PG hEx;PG) and hydrogen production(hEn;H2 hEx;H2 ) are taken into account. Results show that the optimal S/B ratios of RM TM200 TM250 and TM300 are 0.354 0.443 0.593 and 0.760 respectively occurring at the carbon boundary points (CBPs) where the maximum values of hEn;PG hEx;PG hEn;H2 and hEx;H2 are also achieved. At CBPs torrefied microalgae as feedstock lower thehEn;PG hEx;PG hEn;H2 and hEx;H2 because of their improved calorific value after undergoing torrefaction and the increased plasma energy demand compared to the RM. However beyond CBPs the torrefied feedstock displays better performance. A comparative life cycle analysis indicates that TM300 exhibits the highest greenhouse gases (GHG) emissions and the lowest net energy ratio (NER) due to the indirect emissions associated with electricity consumption.
Layered Transition Metal Selenophosphites for Visible Light Photoelectrochemical Production of Hydrogen
Jun 2021
Publication
The growing consumption of global energy has posed serious challenges to environmental protection and energy supplies. A promising solution is via introducing clean and sustainable energy sources including photoelectrochemical hydrogen fuel production. 2D materials such as transition metal trichalcogenphosphites (MPCh3) are gaining more and more interest for their potential as photocatalysts. Crystals of transition metal selenophosphites namely MnPSe3 FePSe3 and ZnPSe3 were tested as photocatalysts for the hydrogen evolution reaction (HER). ZnPSe3 is the one that exhibited the lowest overpotential and the higher response to the light during photocurrent experiments in acidic media. For this reason among the crystals in this work it is the most promising for the photocatalyzed production of hydrogen.
Determinants of Consumers’ Purchasing Intentions for the Hydrogen-Electric Motorcycle
Aug 2017
Publication
In recent years increasing concerns regarding the energy costs and environmental effects of urban motorcycle use have spurred the development of hydrogen-electric motorcycles in Taiwan. Although gasoline-powered motorcycles produce substantial amounts of exhaust and noise pollution hydrogen-electric motorcycles are highly energy-efficient relatively quiet and produce zero emissions features that suggest their great potential to reduce the problems currently associated with the use of motorcycles in city environments. This study identified the significant external variables that affect consumers’ purchase intentions toward using hydrogen-electric motorcycles. A questionnaire method was employed with a total of 300 questionnaires distributed and 233 usable questionnaires returned yielding a 78% overall response rate. Structural equation modeling (SEM) was applied to test the research hypothesis. The research concluded that (1) product knowledge positively influenced purchase intentions but negatively affected the perceived risk; (2) perceived quality via hydrogen-electric motorcycles positively influenced the perceived value but negatively affected the perceived risk; (3) perceived risk negatively affected the perceived value; and (4) the perceived value positively affected purchase intentions. This study can be used as a reference for motorcycle manufacturers when planning their marketing strategies.
Hydrogen Embrittlement of a Boiler Water Wall Tube in a District Heating System
Jul 2022
Publication
A district heating system is an eco-friendly power generation facility with high energy efficiency. The boiler water wall tube used in the district heating system is exposed to extremely harsh conditions and unexpected fractures often occur during operation. In this study a corrosion failure analysis of the boiler water wall tube was performed to elucidate the failure mechanisms. The study revealed that overheating by flames was the cause of the failure of the boiler water wall tube. With an increase in temperature in a localized region the microstructure not only changed from ferrite/pearlite to martensite/bainite which made it more susceptible to brittleness but it also developed tensile residual stresses in the water-facing side by generating cavities or microcracks along the grain boundaries inside the tube. High-temperature hydrogen embrittlement combined with stress corrosion cracking initiated many microcracks inside the tube and created an intergranular fracture.
The Effects of Perceived Barriers on Innovation Resistance of Hydrogen-Electric Motorcycles
Jun 2018
Publication
As environmental awareness among the public gradually improves it is predicted that the trend of green consumption will make green products enter the mainstream market. Hydrogen-electric motorcycles with eco-friendly and energy-efficient characteristics have great advantages for development. However as a type of innovative product hydrogen-electric motorcycles require further examination with regard to consumer acceptance and external variables of the products. In this study consumer behavioral intention (BI) for the use of hydrogen-electric motorcycles and its influencing factors are discussed using innovation resistance as the basis and environmental concern as the adjusting variable. Consumers’ willingness-to-pay (WTP) for hydrogen-electric motorcycles is estimated using the contingent valuation method (CVM). The results found that (1) perception barriers viz. usage barrier value barrier risk barrier tradition barrier and price barrier are statistically significant whereas image barrier is not; (2) a high degree of environmental concern will reduce the consumers’ innovation resistance to the hydrogen-electric motorcycles; (3) up to 94.79% of the respondents of the designed questionnaire suggested that the promotion of hydrogen-electric motorcycles requires a subsidy of 21.9% of the total price from the government. The mean WTP of consumers for the purchase of hydrogen-electric motorcycles is 10–15% higher than that of traditional motorcycles.
A Critical Review on the Principles, Applications, and Challenges of Waste-to-hydrogen Technologies
Sep 2020
Publication
Hydrogen sourced from energy recovery processes and conversion of waste materials is a method of providing both a clean fuel and a sustainable waste management alternative to landfill and incineration. The question is whether waste-to–hydrogen can become part of the zero-carbon future energy mix and serve as one of the cleaner hydrogen sources which is economically viable and environmentally friendly. This work critically assessed the potential of waste as a source of hydrogen production via various thermochemical (gasification and pyrolysis) and biochemical (fermentation and photolysis) processes. Research has shown hydrogen production yields of 33.6 mol/kg and hydrogen concentrations of 82% from mixed waste feedstock gasification. Biochemical methods such as fermentation can produce hydrogen up to 418.6 mL/g. Factors including feedstock quality process requirements and technology availability were reviewed to guide technology selection and system design. Current technology status and bottlenecks were discussed to shape future development priorities. These bottlenecks include expensive production and operation processes heterogeneous feedstock low process efficiencies inadequate management and logistics and lack of policy support. Improvements to hydrogen yields and production rates are related to feedstock processing and advanced energy efficiency processes such as torrefaction of feedstock which has shown thermal efficiency of gasification up to 4 MJ/kg. This will affect the economic feasibility and concerns around required improvements to bring the costs down to allow waste to viewed as a serious competitor for hydrogen production. Recommendations were also made for financially competitive waste-to-hydrogen development to be part of a combined solution for future energy needs.
The Optimization of Hybrid Power Systems with Renewable Energy and Hydrogen Generation
Jul 2018
Publication
This paper discusses the optimization of hybrid power systems which consist of solar cells wind turbines fuel cells hydrogen electrolysis chemical hydrogen generation and batteries. Because hybrid power systems have multiple energy sources and utilize different types of storage we first developed a general hybrid power model using the Matlab/SimPowerSystemTM and then tuned model parameters based on the experimental results. This model was subsequently applied to predict the responses of four different hybrid power systems for three typical loads without conducting individual experiments. Furthermore cost and reliability indexes were defined to evaluate system performance and to derive optimal system layouts. Finally the impacts of hydrogen costs on system optimization was discussed. In the future the developed method could be applied to design customized hybrid power systems.
Photocatalytic Hydrogen Production by Photo-Reforming of Methanol with One-pot Synthesized Pt-containing TiO2 Photocatalysts
Jul 2019
Publication
Functionalization of semiconductors by metallic nanoparticle is considered to be one of the most effective procedure to improve photocatalytic hydrogen production. Photodeposition is frequently used for functionalization but particle sizes and dispersions are still difficult to control. Here Pt functionalization is achieved in a one-pot synthesis. The as-prepared samples are compared to reference materials prepared by conventional photodeposition and our results confirm that small and well-dispersed nanoparticles with superior stability are obtained by one-pot synthesis. The enhanced stability is attributed to a limited leaching of Pt nanoparticles during illumination likely caused by the preferable interaction of small well dispersed Pt nanoparticles with the TiO2 support material. In addition our results demonstrate that Na-residues are detrimental for the photocatalytic performance and washing in acidic solution is mandatory to effectively reduce the sodium contamination.
Thermocatalytic Hydrogen Production Through Decomposition of Methane-A Review
Oct 2021
Publication
Consumption of fossil fuels especially in transport and energy-dependent sectors has led to large greenhouse gas production. Hydrogen is an exciting energy source that can serve our energy purposes and decrease toxic waste production. Decomposition of methane yields hydrogen devoid of COx components thereby aiding as an eco-friendly approach towards large-scale hydrogen production. This review article is focused on hydrogen production through thermocatalytic methane decomposition (TMD) for hydrogen production. The thermodynamics of this approach has been highlighted. Various methods of hydrogen production from fossil fuels and renewable resources were discussed. Methods including steam methane reforming partial oxidation of methane auto thermal reforming direct biomass gasification thermal water splitting methane pyrolysis aqueous reforming and coal gasification have been reported in this article. A detailed overview of the different types of catalysts available the reasons behind their deactivation and their possible regeneration methods were discussed. Finally we presented the challenges and future perspectives for hydrogen production via TMD. This review concluded that among all catalysts nickel ruthenium and platinum-based catalysts show the highest activity and catalytic efficiency and gave carbon-free hydrogen products during the TMD process. However their rapid deactivation at high temperatures still needs the attention of the scientific community.
Development of Electric Power Generator by Using Hydrogen
Nov 2023
Publication
In this research we developed a hydrogen (H2 ) electric generator in an H2 generation system based on chemical reactions. In the experiment we tested the performance of the H2 electric generator and measured the amount of H2 generated. The maximum output was 700 W and the thermal efficiency was 18.2%. The theoretical value and measured value were almost the same and the maximum error was 4%.
Design Challenges in Hydrogen-Fueled Rotary Engine-A Review
Jan 2023
Publication
The rotary engine (RE) is a potential power plant for unmanned aerial vehicles (UAVs) and automobiles because of its structural and design merits. However it has some serious drawbacks such as frequent maintenance requirements and excessive fuel consumption. This review paper presents the current status of hydrogen-fueled rotary engine (HRE) technology and identifies the existing research and development gaps in combustion efficiency and performance of this engine that might benefit transportation sector. Focusing primarily on the research from past ten years the crucial challenges encountered in hydrogen-powered rotary engines have been reviewed in terms of knock hydrocarbon (HC) emissions and seal leakages. The paper identifies the recent advances in design concepts and production approaches used in hydrogen-fueled rotary engines such as geometric models of trochoid profiles port configurations fuel utilization systems and currently available computational fluid dynamics (CFD) tools. This review article is an attempt to collect and organize literature on existing design methods up to date and provide recommendations for further improvements in RE technology.
Impacts of Load Profiles on the Optimization of Power Management of a Green Building Employing Fuel Cells
Dec 2018
Publication
This paper discusses the performance improvement of a green building by optimization procedures and the influences of load characteristics on optimization. The green building is equipped with a self-sustained hybrid power system consisting of solar cells wind turbines batteries proton exchange membrane fuel cell (PEMFC) electrolyzer and power electronic devices. We develop a simulation model using the Matlab/SimPowerSystemTM and tune the model parameters based on experimental responses so that we can predict and analyze system responses without conducting extensive experiments. Three performance indexes are then defined to optimize the design of the hybrid system for three typical load profiles: the household the laboratory and the office loads. The results indicate that the total system cost was reduced by 38.9% 40% and 28.6% for the household laboratory and office loads respectively while the system reliability was improved by 4.89% 24.42% and 5.08%. That is the component sizes and power management strategies could greatly improve system cost and reliability while the performance improvement can be greatly influenced by the characteristics of the load profiles. A safety index is applied to evaluate the sustainability of the hybrid power system under extreme weather conditions. We further discuss two methods for improving the system safety: the use of sub-optimal settings or the additional chemical hydride. Adding 20 kg of NaBH4 can provide 63 kWh and increase system safety by 3.33 2.10 and 2.90 days for the household laboratory and office loads respectively. In future the proposed method can be applied to explore the potential benefits when constructing customized hybrid power systems.
Life Cycle Assessment of Carbon Footprint in Public Transportation - A Case Study of Bus Route NO. 2 in Tainan City, Taiwan
Apr 2019
Publication
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.
Alternative Gaseous Fuels for Marine Vessels towards Zero-Carbon Emissions
Nov 2023
Publication
The maritime industry is recognized as a major pollution source to the environment. The use of low- or zero-carbon marine alternative fuel is a promising measure to reduce emissions of greenhouse gases and toxic pollutants leading to net-zero carbon emissions by 2050. Hydrogen (H2 ) fuel cells particularly proton exchange membrane fuel cell (PEMFC) and ammonia (NH3 ) are screened out to be the feasible marine gaseous alternative fuels. Green hydrogen can reduce the highest carbon emission which might amount to 100% among those 5 types of hydrogen. The main hurdles to the development of H2 as a marine alternative fuel include its robust and energy-consuming cryogenic storage system highly explosive characteristics economic transportation issues etc. It is anticipated that fossil fuel used for 35% of vehicles such as marine vessels automobiles or airplanes will be replaced with hydrogen fuel in Europe by 2040. Combustible NH3 can be either burned directly or blended with H2 or CH4 to form fuel mixtures. In addition ammonia is an excellent H2 carrier to facilitate its production storage transportation and usage. The replacement of promising alternative fuels can move the marine industry toward decarbonization emissions by 2050.
Hydrogen Trapping and Embrittlement in Metals - A Review
Apr 2024
Publication
Hydrogen embrittlement in metals (HE) is a serious challenge for the use of high strength materials in engineering practice and a major barrier to the use of hydrogen for global decarbonization. Here we describe the factors and variables that determine HE susceptibility and provide an overview of the latest understanding of HE mechanisms. We discuss hydrogen uptake and how it can be managed. We summarize hydrogen trapping and the techniques used for its characterization. We also review literature that argues that hydrogen trapping can be used to decrease HE susceptibility. We discuss the future research that is required to advance the understanding of HE and hydrogen trapping and to develop HE-resistant alloys.
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