Search

Hydrogen carriers are attractive alternative fuels for the shipping sector. They are zero-emission, have high energy densities, and are safe, available, and easy to handle. Sodium borohydride, potassium borohydride, dibenzyltoluene, n-ethylcarbazole, and ammoniaborane are hydrogen carriers with high theoretical energy densities. The energy density is paramount to implementing hydrogen carriers as a high energy density enables compact and lightweight storage. The effective energy density depends on integrating heat and masses with energy converters. This combination defines the energy efficiency and, thus, the energy density of the system. This paper addresses the effective energy density of the hydrogen carriers, including the dehydrogenation process. Using a 0D model, we combined the five carriers with two types of fuel cells, namely proton exchange membrane (PEM) and solid oxide fuel cells (SOFC), an internal combustion engine and a gas turbine. N-ethylcarbazole and dibenzyltoluene offer medium energy densities, reaching almost 4 MJ/kg. However, the effective energy density of sodium borohydride and ammoniaborane is very high, up to 15 MJ/kg, including the energy converter. This is similar to the energy density of marine diesel oil combined with an internal combustion engine. Thus, we conclude hydrogen carriers are alternative fuels that deserve more attention because of their strong potential to make shipping zero-emission. [ABSTRACT FROM AUTHOR]

The escalating accumulation of polypropylene (PP) plastic waste poses significant environmental challenges, requiring innovative waste management strategies. Pyrolysis of plastic waste presents a promising approach for sustainable production of alternative fuels. However, pyrolysis oil possesses undesirable properties for direct fuel applications, requiring additional upgrading steps before being utilized for specific purposes. Fractionation offers an effective method for the separation of pyrolysis oil. This study investigates the pyrolysis of PP plastic waste with three-stage condensers system, focusing on the effect of temperature and fractional condensation on the yield and characteristics of pyrolysis oil. Experiments were conducted within temperature range of 400, 410, 425, 430, 440, to 450 °C, with the aim of optimizing the generation of liquid products. The pyrolysis vapors were sequentially passed through three condensers. Results indicate that the maximum bio-oil was obtained at 450 °C as optimum temperature, which consists of 2.32% gases (C1-C5), 41.94% gasoline (C6-C11), 44.15% kerosene (C12-C20), and 11.59% residue (> C20). The distribution of compounds was influenced by fractional condensers, with the highest relative contents of compounds obtained from condenser 1, 2, and 3 were gasoline (79.28%), kerosene (51.97%), and gasoline (55.21%), respectively. Gas Chromatography-Mass Spectrometry (GC-MS) was used to characterize the chemical and physical properties of bio-oils. The characterization results reveal that the pyrolysis oil obtained from PP plastic waste are dominated with 1-heptene-5-methyl (C8H16). The composition of pyrolysis oil demonstrated favourable and suitable properties for potential applications as renewable fuels and chemical feeds [ABSTRACT FROM AUTHOR]

This study develops a framework for designing hydrogen supply chains (HSC) in island territories using Mixed Integer Linear Programming (MILP) with a multi-period approach. The framework minimizes system costs, greenhouse gas emissions, and a risk-based index. Corsica is used as a case study, with a Geographic Information System (GIS) identifying hydrogen demand regions and potential sites for production, storage, and distribution. The results provide an optimal HSC configuration for 2050, specifying the size, location, and technology while accounting for techno-economic factors. This work integrates the unique geographical characteristics of islands using a GIS-based approach, incorporates technology readiness levels, and utilizes renewable electricity from neighboring regions. The model proposes decentralized configurations that avoid hydrogen transport between grids, achieving a levelized cost of hydrogen (LCOH) of €8.54/kg. This approach offers insight into future options and incentive mechanisms to support the development of hydrogen economies in isolated territories. [Display omitted] • A framework for optimal hydrogen supply chain design in island territories is defined. • The multi-period problem is modelled using Mixed Integer Linear Programming. • The framework aims to minimize cost, emissions, and a risk-based index. • Island-specific geography is integrated using a Geographic Information System. • The hydrogen produced meets the transportation demand of Corsica from 2025 to 2050. [ABSTRACT FROM AUTHOR]

This article discusses advances in the design of hydrogen fuel engines; the main characteristics of the hybrid engine are studied; prospects for further research are outlined; development and improvement of engine designs, research of processes in engines running on natural gas and hydrogen. Transport is one of the key elements of modern civilization. Its condition and development prospects largely depend on the ability to supply transport power plants with fuel. The depletion of liquid hydrocarbon fuel reserves and problems of environmental pollution may present humanity with a choice - either to reduce transport transportation or to find new ways to supply energy to transport. OBJECTIVE: To review the electrochemical technologies used for the production of hydrogen at gas stations and the operation of hybrid electric vehicle engines using fuel cell batteries. Conduct a comparative analysis of the production and use of energy by electrochemical and traditional methods in vehicles. METHODS are based on analysis of literature data and mathematical calculations. For a passenger electric vehicle, the amount of electricity that can be obtained in a fuel cell by processing 1 kg of hydrogen was calculated. It has been shown that the specific fuel consumption for a hydrogen electric vehicle averages 1 kg of hydrogen per 100 km. Hydrogen has the potential to be the sustainable fuel of the future, reducing global dependence on fossil fuel resources and reducing carbon emissions from the transportation industry. [ABSTRACT FROM AUTHOR]

Refuse-derived fuel (RDF) utilization as an alternative fuel has encountered obstacles in complying with industrial quality standards. This study aimed to improve landfill-mined RDF quality for acceptable calorific values (CV), moisture, volatile, ash, fixed carbon, chlorine, and sulfur contents by the cement industry and coal-fired steam power plant. For eight consecutive working days, a minimum of 100 kg of mined material was sampled randomly from transport trucks. Each sample was separated into three fractions: fine (< 10 mm), medium (10-30 mm), and rough (> 30 mm). RDF ratio of plastic: wood and garden waste, originating from a rough fraction, were set at 20:80 to 80:20 with a 10-point interval, including controls at 0:100 and 100:0. Moisture, CV, volatile solids, ash, and fixed carbon contents of RDF were determined by ASTM codes, while chlorine and sulfur used APHA/AWWA/WEF standard methods. The RDF optimum ratio was 40:60, which produced CV, air-dried moisture, volatile solids, ash, fixed carbon, chlorine, and sulfur contents were 25.23 ± 0.53 MJ kg-1, 26.11 ± 2.84%, 75.20 ± 1.21%, 21.18 ± 0.76%, 3.62 ± 0.63%, 0.129 ± 0.009%, and 0.058 ± 0.004%, respectively. These results met industrial RDF quality standards except for moisture, ash, and fixed carbon contents, which needed process improvements at the RDF processing plant. [ABSTRACT FROM AUTHOR]

The substitution of municipal solid waste (MSW) for pulverized coal reduces the dependence on fossil fuels, lowers production costs in energy-intensive industries, and helps decrease carbon emissions. The primary method of utilizing MSW as fuel is mixed combustion with pulverized coal. This paper employs a thermogravimetric analysis to study the combustion characteristics and perform a kinetic analysis of a mixture of MSW and pulverized anthracite coal. The simulated MSW is composed of three representative components: polyvinyl chloride (PVC), polyethylene (PE), and straw (a typical biomass). The experimental results indicate that the combustion process of MSW is more complex than that of anthracite. The initial ignition temperature of MSW is 334 °C, whereas that of anthracite is 551 °C. As the proportion of MSW increases, the weight loss stages in the combustion curve of the mixture become more numerous, and the ignition temperature gradually decreases. Moreover, the combustion performance of the MSW–anthracite mixture improves, with the combustibility index Rm rising from 0.131 to 0.235. The combustion process of MSW–anthracite mixtures was analyzed using the random pore model (RPM), the unreacted core model (URCM), and the volumetric model (VM). Among these, the VM was found to be the most suitable kinetic model for the combustion process. The activation energies for the combustion processes of anthracite, 20% MSW-80% anthracite, 40% MSW-60% anthracite, 60% MSW-40% anthracite, 80% MSW-20% anthracite, and MSW were calculated to be 152.05 kJ/mol, 80.51 kJ/mol, 51.05 kJ/mol, 40.87 kJ/mol, 33.41 kJ/mol, and 32.17 kJ/mol, respectively. The obtained results indicate that MSW is a high-performance fuel with significant application potential. [ABSTRACT FROM AUTHOR]

This study aims to predict the economic transition pathway for alternative fuels in accordance with the 2023 IMO GHG Strategy goals. The assessment considers the impact of alternative fuel transition on fuel costs (∆COSTFuel,t), carbon emission costs (∆COSTCO2 eq,t), and ship new/retrofit costs (∆COSTship). The parameters and boundary conditions were set based on the current status and trends in the international shipping industry, as determined from previous research, to predict the economic transition pathway for alternative fuels. The results show that in 2050, with a standardized economic efficiency of 130%, profit will reach its maximum value, approximately −54,000 million USD. The study standardized fuel ΔCOSTj, normalized, and ΔNPV%j, normalized as a basis for adjusting penetration rates. At this time, considering fuel costs and NPV%, the composition of alternative fuels is as follows: bio-LNG, bio-Methanol, e-LNG, e-Methanol, e-Ammonia, BD, and Fossil-LNG, with shares of 18.56%, 4.00%, 25.64%, 6.00%, 10.00%, 28.00%, and 0%, respectively. Compared to conventional marine fuel HFO, the increase ranges from 23.54% to 69.50% in the 2030s, 0.52% to 0.55% in the 2040s, and decreases by 6.88%–14.69% in 2050. Using more LNG and BD in the 2040s and 2050 is an alternative way to achieve a better economic fuel transition. Moreover, the economic penetration rate combination set in this study can achieve sufficiently small ∆COSTT,t and sufficiently large NPVΔt under specific assumptions and boundary conditions, rather than an absolute minimum ∆COSTT,t or the absolute maximum NPVΔt. The results revealed that no single alternative fuel has a comprehensive advantage in reducing carbon intensity and economic performance at all times. Given the uncertainties in the supply chain, cost-effectiveness, and infrastructure for Methanol and Ammonia, LNG and BD play a crucial role in the transition of international shipping fuels. Our work provides a fundamental and comprehensive prediction of fuel transition based on the current status and trends in the international shipping industry. [ABSTRACT FROM AUTHOR]

The article examines the features of the combustion process of hydrogen-containing gas (syn-gas) in the working cylinder of a spark-ignition internal combustion engine. The main objective of the study is to evaluate the heat release parameters of syngas. To achieve this goal, an exper-imental investigation was conducted to assess the nature of syngas combustion and establish its regularity. The most significant result is the derivation of dependencies for determining the cur-rent value of the combustion characteristic index m and the combustion duration φz in Professor I.I.Vibe's heat release model for spark-ignition engines operating on syngas, with an air excess ratio α ranging from 1.0 to 2.2 and hydrogen content in the fuel composition varying between 30% and 100% by volume. The significance of the obtained results lies in the establishment of the variability of the combustion index m (ranging from 1.6 to 5.5) in Professor I.I.Vibe's semi-empirical heat release model, which more closely corresponds to the actual heat release law ob-served in experimental studies. The proposed dependencies for determining m and φz allow for accounting the specific features of the syngas combustion process in spark-ignition engines, thereby significantly improving the accuracy of determining the indicated pressure in the work-ing cylinder (the relative root-mean-square error does not exceed 4.5%), which, in turn, enhanc-es the accuracy of assessing the engine's energy and economic parameters. The results of this study can be applied in the design and construction of new spark-ignition engines running on alternative fuel.

The increasing energy demands, especially in transportation sector, and the challenges of excess pollution and environmental degradation caused due to the conventional fuels, as well as their limited availability has highlighted the need to look for alternative fuels to sustain future needs. Methane is capable of catering to these demands due to its wide availability, both in renewable and non-renewable energy sources. The present work explores the effect of methane supplementation on the performance and emission characteristics as well as the vibrations in internal combustion engines. A four-stroke compression ignition engine is modified to run as a methane-diesel dual fuel engine where methane is inducted through intake manifold and diesel is directly injected into cylinder. Tests are performed by varying engine load and methane energy levels up to 75%. Our study shows that the participation of methane at lower load conditions is weak due to its higher auto ignition temperature and higher calorific value. The emissions, particularly CO and NO, are observably higher at 75% load conditions due to the efficient combustion and higher temperature at higher load conditions. The vibration studies on the dual fuel combustion indicates that the introduction of methane also suppresses the frequency spectrum of combustion noise and reduces the ringing intensity level of vibration for complete spectrum of engine loads, with the effect being prominent at higher loads. Overall, our results suggests that combustion of methane in dual fuel diesel engine shows distinct characteristics at contrasting load conditions. [ABSTRACT FROM AUTHOR]

This paper presents an overview of the status and prospects of fuel cell electric vehicles (FC-EVs) for grid integration. In recent years, renewable energy has been explored on every front to extend the use of fossil fuels. Advanced technologies involving wind and solar energy, electric vehicles, and vehicle-to-everything (V2X) are becoming more popular for grid support. With recent developments in solid oxide fuel cell electric vehicles (SOFC-EVs), a more flexible fuel option than traditional proton-exchange membrane fuel cell electric vehicles (PEMFC-EVs), the potential for vehicle-to-grid (V2G)'s implementation is promising. Specifically, SOFC-EVs can utilize renewable biofuels or natural gas and, thus, they are not limited to pure hydrogen fuel only. This opens the opportunity for V2G's implementation by using biofuels or readily piped natural gas at home or at charging stations. This review paper will discuss current V2G technologies and, importantly, compare battery electric vehicles (BEVs) to SOFC-EVs for V2G's implementation and their impacts. [ABSTRACT FROM AUTHOR]

Due to the significant increase in transportation, traditional fossil fuels utilised in internal combustion engines will only be accessible for a limited duration. Additionally, the harmful pollutants produced by these fuels, including CO, NOx, unburned hydrocarbons, smoke, and a small amount of particulate matter, have a severe negative impact on the environment. Although biodiesel proves efficient without necessitating engine modifications, its performance is hindered by its higher viscosity. Consequently, this research aims to enhance performance by introducing acetylene alongside tamanu methyl ester (biodiesel); however, this approach results in elevated NOx levels. To mitigate NOx emissions, a combination of ethanol and biodiesel is employed. This study investigates the performance and emission attributes of Acetylene + TME90E10 as the fuel. The combustion pressure and heat release rate of TME90E10 with 6 lpm, improved by 5.41% and 9.1% than diesel. When compared to regular diesel fuel, the introduction of 6 l per minute of acetylene with TME90E10 yields a substantial 24.4% decrease in hydrocarbon (HC) emissions. Furthermore, employing TME90E10 at the same acetylene flow rate demonstrates the lowest carbon monoxide (CO) emissions, registering at 0.07%, in contrast to the 0.13% emissions observed throughout the exhaust cycle when using pure diesel fuel. [ABSTRACT FROM AUTHOR]

The escalating global demand for oil, coupled with declining fossil fuel production, prompts the urgent exploration of renewable alternatives. To address this challenge, researchers are actively seeking environmentally friendly fuels like biodiesel. Among potential feedstocks, oil that is produced from salmon smoking process during industry emerges as a promising option. Smoked salmon oil could be a challenge when producing biodiesel due to its high content of omega-3 compounds. Using homogenous commercial catalyst from alkali to achieve the highest yield from salmon smoking oil was the aim of the current study. A Box–Behnken design and response surface methodology in Design Expert software (version 13) was used to study the effect of four main factors on the biodiesel yield from salmon smoking oil. The optimum biodiesel values were 70°C, 90 min, 0.753 wt.%, and 20 wt.% for temperature, reaction time, sodium hydroxide concentration, and methanol concentration, respectively. At these optimum values, the highest biodiesel production was 92.0% with fatty acid methyl ester contents of 83.4% and conversion efficiency of 77%. Thin-layer chromatography and thermal gravimetric analysis confirmed the successful production of biodiesel at optimized conditions. Using Aspen Plus simulation software confirmed the cost-effectiveness of the homogenous catalyst used for enhancing biodiesel production from salmon smoking oil. [ABSTRACT FROM AUTHOR]

Palm sap is one of the raw materials for making bioethanol as an alternative energy source. Bioethanol is ethanol that can be produced through fermentation, distillation and purification processes. This research aims to determine the effect of storage time for palm sap on the quality of bioethanol raw materials. This research used a completely randomized design with storage time as treatment and three repetitions for each treatment. The parameters observed were yield, ethanol content, density, specific gravity and heating value. The research results show that storage time has an effect on the quality of bioethanol, such as yield ranging from 9.73% - 12.93%, ethanol content ranging from 21.57% - 28.47%, density ranging from 0.91 g/ml - 0.92 g/ml, specific gravity ranges from -7.19 - 32.53 and calorific value ranges from 9981.42 kcal/g - 10864.30 kcal/g. Based on the research results, the storage time for palm sap affects the quality of the bioethanol raw material, so the storage time for palm sap is no more than 6 days because it can affect the quality of the bioethanol. [ABSTRACT FROM AUTHOR]

The search for alternative fuels compatible with internal combustion engines has escalated as a result of worldwide pollution and the exhaustion of fossil resources. Alcoholic fuels, such as methanol, ethanol, butanol, and fusel alcohols, are being considered as viable alternatives to gasoline and gaseous fuels. This review analyzes the effects of alcoholic fuels on the performance, combustion, and emissions of spark-ignition (SI) engines. It specifically focuses on several fuel supply modes, including blending, dual mode, and dedicated (100%) modes. This paper examines the impact of fuel characteristics on engine parameters and investigates various operating settings to improve performance. Furthermore, it tackles the existing difficulties linked to the use of alcoholic fuel blends in spark-ignition (SI) engines and puts forward alternative remedies. Special emphasis is placed on ethanol, which has shown to possess adequate fuel mixture characteristics for spark-ignition (SI) engines in current circumstances. The analysis identifies deficiencies in current research, particularly concerning the combustion of fusel alcohol in direct injection (DI) and port-fuel injection (PFI) engines. It underscores the necessity for more investigations into the long-term durability of engines and the compatibility of materials with alcohol fuels. This article intends to provide a thorough overview that will direct future research and development endeavors toward achieving a more sustainable and efficient utilization of alcoholic fuels in internal combustion engines. [ABSTRACT FROM AUTHOR]

Biofuels are the most essential types of alternative fuels, which currently have significant potential to reduce CO2 emissions compared to fossil fuels. Methanol is a more efficient fuel than petrol due to its physicochemical properties, such as a higher latent heat of vaporization, research octane number, and heat of combustion of the fuel–air mixture. Also, biomethanol is cheaper than traditional petrol and diesel fuel for agricultural countries. The authors have proposed a new approach to improve the characteristics and efficiency of methanol diesel engines by using biomethanol mixed with hydrogen instead of pure biomethanol. Using a hydrogen–biomethanol mixture in modern engines is an effective method because hydrogen is a carbon-free, low-ignition, highest-flame-rate, high-octane fuel. A small quantity of hydrogen added to biomethanol and its combustion in an engine with a heat exchanger increases the combustion temperature and heat release, increases engine power, and reduces fuel consumption. This article presents experimental results of methanol combustion and a hydrogen-in-methanol mixture if hydrogen was retained due to the utilization of the heat of the exhaust gases. The tests were carried on a single-cylinder experimental engine with an injection of liquid methanol and gaseous hydrogen mixtures. The experiments showed that green hydrogen generated onboard the car due to the utilization of heat significantly reduced fuel costs of engines of vehicles and technological installations. It was established a hydrogen gaseous mixture addition of up to 5% by mass to methanol requires a corresponding change in the coefficient of excess air to λ = 1.25. Also, using an additional hydrogen mixture requires adjustment at the ignition moment in the direction of its decrease by 4–5 degrees of the engine crankshaft. Hydrogen gas mixture addition reduced methanol consumption, reaching a maximum reduction of 24%. The maximum increase in power was 30.5% based on experimental data. The reduction in the specified fuel consumption, obtained after experimental tests of the methanol research engine on the stand, can be implemented on the vehicle engines and technological installations equipped with an onboard heat recovery system. Such a system, due to the utilization of heat and the supply of additional hydrogen, can be implemented for engines that work on any alternative or traditional fuels. [ABSTRACT FROM AUTHOR]

In order to develop a retrofit compatible ammonia mixed combustion engine for automobiles, we utilized the property of ammonia to dissolve easily in water and used a "water mixed fuel generation device" developed by the National Fisheries University to produce ammonia water mixed fuel. An experiment was carried out in which ammonia was injected as a liquid at normal temperature under atmospheric pressure. To clarify the combustion characteristics and DPF performance when ammonia is used in a small high-speed engine, 214kW/3,101min-1 diesel engine with a DPF was operated using a fuel made from a mixture of gas oil and ammonia water, and the engine performance and characteristics of NOx, PM, and DPF were analyzed. As a result, it was clarified that ammonia can also be used in small high-speed engines. [ABSTRACT FROM AUTHOR]

The purpose of this study is to evaluate the primary energy consumption and GHG emissions of hydrogen, synthetic fuels, and biofuels in the Well-to-Wheel (WtW) process. The passenger cars considered in Tank-to-Wheel include gasoline vehicles (ICEV-G), diesel vehicles (ICEV-D), hybrid electric vehicles (HEV), battery electric vehicles (BEV), and fuel cell electric vehicles (FCEV). The results show that Ethanol from sugar beet has the lowest GHG emissions of the other fuels. It can reduce GHG emissions by 93% compared to conventional petroleum-based fuels. In addition, ICEV (ICEV-G, ICEV-D, HEV) powered by e-fuel or biofuels had lower GHG emissions in WtW than BEV. Therefore, when using carbon-neutral fuels, ICEV is a more effective means of reducing GHG emissions than BEV. [ABSTRACT FROM AUTHOR]

To reduce fossil energy consumption and achieve global carbon neutrality, it is essential to develop alternative fuels such as hydrogen (H2) and dimethyl ether (DME). In order to analyze the energy-mass conversion behavior of alternative fuels for power units (including gas turbines) and to explore the principles of efficiency enhancement, the exergy loss characteristics of methane (CH4)/air laminar premixed flames blended with H2/DME were investigated. The effects of blending ratio, unburned gas temperature, operating pressure, and equivalence ratio on the exergy loss fraction were considered. The results indicated that DME and H2 had opposite effects on the total exergy loss fraction of the premixed flame. Elevating the operating pressure was beneficial to reducing the exergy loss caused by chemical reactions and exhaust gas, which more significantly enhanced the exergy efficiency of each fuel mixture compared to increasing the unburned gas temperature. The exergy loss fraction due to the exhaust gas was also lower in the lean flame, suggesting that DME could be a promising alternative to CH4 in this scenario. As the exergy loss fraction due to chemical reaction was minimized at an equivalence ratio of 1.2, a variable equivalence ratio operating strategy was expected to further optimize the exergy efficiency of each fuel mixture. Furthermore, response functions of the total exergy loss fraction, which considered the combined effects of multiple operating parameters, were constructed. These response functions allow the total exergy loss fractions of CH4 premixed flames with high DME blending ratios and moderate H2 blending ratios to be quantified. The results from this study enable a deeper understanding of the energy-mass conversion behavior of systems with added H2/DME during combustion and provide theoretical support for the application of alternative fuels to more complex configurations of industrial burners. [ABSTRACT FROM AUTHOR]

This work presents a comprehensive Social Life Cycle Assessment (S-LCA) and Social Cost-Benefit Analysis (S-CBA) conducted as part of a research project, studying biofuel production for the maritime and aviation sectors, from various types of non-food waste biomasses. The inclusion of social considerations complements and expands on the environmental and economic ones. The importance of social group criteria was determined through expert questionnaires, leading to the identification of social impacts groups and social criteria from stakeholders across participating countries. The results successfully identified and quantified social impacts, and align with those reported in similar cases in relevant literature. Social Cost-Benefits, monetarizing social factors, demonstrated several social benefits, including reduction in Greenhouse Gas Emissions. However, it also highlighted social costs, such as Economic Costs associated with the initial investment. The study revealed critical social hotspots within the impact categories, making significant strides in understanding the social impacts of biofuel production, providing valuable insights for decision-makers, and contributing to the broader goal of sustainable and socially responsible biofuel production. [ABSTRACT FROM AUTHOR]

The current energy and environmental problems demand the replacement of fossil fuels with renewable fuels. Research shows that hydrogen-enriched CNG fuels enhance the thermal efficiency of diesel engines while reducing gaseous emissions. This experimental work investigates the performance and emissions parameters of a diesel engine in dual fuel mode with hydrogen-enriched Bio-CNG (HBCNG). It is performed on a single-cylinder, four-stroke common rail direct injection (CRDI) diesel engine at 1500 rpm and 3.5 kW. The outcomes of this experiment are compared to a neat diesel operation. It is observed that at low load with 30% gaseous fuel substitution (GFS), brake thermal efficiency decreases by 13.70% and 15.53% for hydrogen and BCNG-enriched diesel, respectively. Similarly, at medium load, with the gaseous mixture of 40% H 2 and 60% BCNG co-combusted with 60% diesel, the BTE improves by 15.83%. At high load, 40% gaseous fuel mixture (40% H 2 + 60% BCNG) combustion with diesel results in 21.25% enhanced BTE. Moreover, at the same load condition and GFS, emissions of HC increase by 41.59%, CO decreases by 30%, CO 2 decreases by 55.36%, and NO x decreases by 25.94%. • The experiment is performed on a common rail direct injection diesel engine. • Hydrogen and Bio-CNG enriched diesel are used as the fuel. • Hydrogen and Bio-CNG mixture proportion in diesel are varied between 0 and 40%. • The engine load is varied between 0 and 80%. • The performance and emission parameters enhanced for 40% gaseous fuel mixture. [ABSTRACT FROM AUTHOR]

The design and application of semiconductor-based photocatalytic technology has a significant impact on addressing the world's energy crisis and environmental degradation by transforming solar energy into chemicals and fuels. Semiconductor-based photocatalyst, ceria (CeO2), which possesses unique 4f electrons, is superior to other metal oxide semiconductors owing to its defect-rich structure, multivalence state, surface oxygen vacancy, photostability, and eco-friendly properties. This critical review is taken up to report the basic mechanistic details of CeO2-based photocatalysis as well as several methods for boosting the activity and stability of this group of photocatalysts. Additionally, numerous photocatalytic applications of CeO2, such as H2 generation by water splitting and CO2 reduction to alcohols and hydrocarbon fuels, are introduced and summarized. In the end, a concise summary of the challenges and potential areas for future research in the synthesis of CeO2-based photocatalysts are also provided. This review is anticipated to provide directions for developing innovative CeO2-based photocatalysts with low-cost and high efficiency, which have the promising application possibilities to fulfill the pressing needs of alternative fuels. Graphical Abtract: [ABSTRACT FROM AUTHOR]

The aviation industry stands at the crossroads of a climate crisis, which significantly contributes to worldwide carbon (C) emissions. To combat this issue and embrace environmental sustainability, the production of sustainable aviation fuel (SAF) from triglyceride-based bio-oils has emerged as a pivotal research and industry pursuit. Traditional aviation fuels that are derived from fossil sources are a major contributor to carbon dioxide (CO2) emissions. However, SAF presents a sustainable and environmentally friendly alternative by harnessing the potential of a used cooking oil (UCO) (triglyceride source), an often-neglected waste stream with significant environmental implications when improperly managed. Among the various conversion methods, the deoxygenation (DO) reaction pathway has emerged as a promising method for converting triglycerides into SAF. However, this emerging technology has significant challenges, which primarily revolve around the selection of feedstocks, catalysts, reaction pathways, and operational parameters. Therefore, this study provides a holistic overview of the DO of a triglyceride-based UCO feedstock as a promising avenue for SAF production by navigating diverse SAF feedstocks, tailoring the DO to enhance versatility, exploring catalyst nuances that impact the DO, and unraveling the optimal operating conditions for superior SAF yields and selectivity. This study concludes that the optimal conditions for SAF production involve utilizing feedstocks with a low free fatty acid (FFA) content, such as canola or high oleic sunflower oils. Employing catalysts with a high surface area and abundant acid sites, such as Zeolite Socony Mobil–5 (ZSM–5), along with metal impregnators such as carbon monoxide (CO) and nickel (Ni) as active metal and promoters, in a down-trickle bed reactor within 300°C–380°C and pressure range of 10–50 bar, proves to be the most effective approach. [ABSTRACT FROM AUTHOR]

Global warming's major cause is the emission of greenhouse-effect gases (GHG), especially carbon dioxide (CO 2) whose main source is the combustion of fossil fuels. Fossil fuels serve as the primary energy source in many industries, including shipping, which is the focus of this study. One of the measures proposed to tackle GHG emissions is the development of green shipping corridors - carbon-free shipping routes that require the transition to alternative fuels, which are gaining competitiveness. One of the reasons for that is carbon pricing, which taxes CO 2 emissions. However, the lack of consensus on the most cost-advantageous alternative fuel in the long run results in the delay of the implementation of green shipping corridors. To make it more accessible for stakeholders to conduct an economic analysis of the various options, a framework to determine and minimize the costs of transitioning from fossil fuels to any alternative fuel is proposed, over the period of one voyage, considering the lost opportunity cost, the deployment cost of bunkering vessels at the necessary call ports, the cost of converting the vessel, the car-bon emissions tax cost, and the fuel cost. This will allow stakeholders to choose the most economical alternative fuel, accelerating the development of green shipping corridor initiatives. To validate the effectiveness of the framework, it was applied in a case study involving a shipowner seeking to transition from heavy fuel oil (HFO) to Ammonia, Hydrogen, Liquefied Natural Gas (LNG), or Methanol. This study faced limitations due to the unknown costs of installing bunkering vessels for Ammonia and Hydrogen. However, it evaluates the cost-effectiveness of alternative fuels, providing insights into their short-term economic viability. The results showed that Hydrogen is the most cost-advantageous fuel until a deployment cost per bunkering vessel of 1,990,285$ for a sailing speed of 22 knots and 2,190,171$ for a sailing speed of 18 knots is reached, after which LNG becomes the most economical option regardless of variations in the carbon tax. Moreover, a sensitivity analysis was conducted to determine the effects of variations in parameters, such as carbon tax, fuel prices and vessel conversion costs in the total cost of each fuel option. Results highlighted that even though HFO remains the most economical fuel option, even when considering a high increase in carbon tax, the cost gap between HFO and alternative fuels narrows significantly with the increase in carbon tax. Furthermore, the sailing speed impacts the fuels' competitiveness, as the cost difference between HFO and alternative fuels decreases at higher speeds. • A tool has been developed to guide the transition from fossil fuels, towards green shipping corridors. • An analysis was conducted to determine if increasing carbon taxes would make alternative fuels more financially viable than HFO. • The study identifies hydrogen as cost-advantageous, followed by LNG, influenced by varying carbon taxes. • Results demonstrated that HFO is still the most economical fuel option, even considering a very high carbon tax. • Challenges lie in uncertain bunkering vessel costs, potential profit, and the need for a model extension for fleet use. [ABSTRACT FROM AUTHOR]

Natural gas and renewable energy carriers play critical roles in the energy supply chain due to rising energy consumption demands and a significant shift toward cleaner energy. However, the requirement to liquefy and regasify liquefied natural gas (LNG) and renewable energy carriers for transportation makes the entire process expensive and challenging. Hence, a floating storage and regasification unit (FSRU) plant provides a solution to the aforementioned problems with the additional benefit of being more affordable, time‐efficient, and having less land footprint requirement than the conventional onshore facility. The proposed integrated FSRU in this study, is powered by renewable energy, including solar and ocean thermal energy. The subsystems of integrated FSRU consist of parabolic dish collectors (PDC), Rankine cycle, organic Rankine cycle (ORC), multi‐stage flashing (MSF) desalination unit, decomposition, reliquefication, and regasification plants, which provide valuable commodities such as freshwater, electricity, hydrogen, and heating. It can also cater to standard multi‐gas harboring vessels for storage and regasification of sustainable energy carriers. The study assesses the performance of the proposed system thermodynamically by analyzing mass, energy, entropy, and exergy balance equations using the engineering equation solver (EES) software. Furthermore, parametric studies were conducted to understand the interlinkage among various variables. The analytical results show that the proposed system is able to produce 1.82 MW of electricity, 2056 kg/day of fresh water, and 338.3 kg/day of hydrogen, achieving an overall system energy efficiency of 32.7% and exergy efficiency of 79.3%. This approach aims to foster energy diversification, enhance energy security, and support the transition toward sustainable energy systems, as well as further the advancement of maritime transport systems. [ABSTRACT FROM AUTHOR]

The conventional fuel used to produce electrical energy and the burning of the conventional fuel causes global warming. Also, there is a depletion of these fuel and hence there is a need of alternative fuels. The biodiesel is a renewable fuel and it is a sustainable fuel. The biodiesel can be derived from waste cooking oil (WCO) as it increases the commercial value of the WCO. The biodiesel has lower oxidation stability and hence onion oil which has good anti oxidation value was added with WCO biodiesel. The engine tests were carried with WCO biodiesel added with onion oil shows that the addition of onion oil improves the thermal efficiency and improvement in cylinder pressure and heat release rate. We conclude that the onion oil can be used as additive to the WCO biodiesel. [ABSTRACT FROM AUTHOR]

In the Korean cement industry, cement is not produced using fossil fuel such as bituminous coal alone but rather using combustible waste as an auxiliary fuel. The standards for using alternative fuel in cement processes are specified in the "Waste Management Laws." However, an analysis process has not been clearly defined, which hinders the development of appropriate standard operating procedures (SOPs) required to objectively evaluate the use of waste as an alternative fuel for cement production. This study proposed clear SOPs to expand the utilization of alternative fuels in cement production, and these procedures were derived by selecting appropriate analysis methods and standards. The thermal, environmental, and quality characteristics of non-recyclable wastes and cement samples treated based on the SOPs were critically examined. Non-recyclable wastes showed a higher calorific value (7010 kcal/kg) and lower chlorine content (0.08 wt.%) compared to bituminous coal, and the cement analysis indicated that the characteristics did not change based on the type of fuel used. Nonrecyclable waste is appropriate for application if processed with a fuel manufacturing system. These findings provide procedural guidelines to promote the use of combustible waste as auxiliary fuels in the cement industry. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Boron / Bor Dergisi is the property of Turkish Energy Nuclear & Research Agency - Boron Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aims to obtain bioethanol according to the Indonesian National Standard (SNI) 7390:2012, obtain Gasohol according to the RON (Research Octane Number) standard in Pertalite, and produce alternative fuels that are more environmentally friendly. The bioethanol production process includes hydrolysis, fermentation, distillation, and adsorption, with Saccharomyces cerevisiae to ferment sugar in pineapple skin into ethanol with a content of 59.62% from a 5-day fermentation process with 4% Saccharomyces cerevisiae, 0.5% urea, 0.5% NPK. Bioethanol is then mixed with Pertalite in the composition of E5 (5 ml of bioethanol mixed with 95 ml of Pertalite) to E25 (25 ml of bioethanol mixed with 75 ml of Pertalite), lowering the flash point of the mixture from 29.8°C (E5) to 28.0°C (E25), increasing the density from 0.7239 gr.(cm3)-1 (E5) to 0.7250 gr.(cm3)-1 (E25) and the viscosity from 0.41 cSt (E5) to 0.49 cSt (E25). Still, the octane number (RON) tends to be stable at 91.4-95.6. As a result, the bioethanol content is close to SNI 99.5%, the bioethanol-Pertalite mixture improves several parameters but lowers the flash point, and the E25 mixture meets the RON standard of 95.6 for Pertalite.

Introduction. In this paper attention is paid to the study of electrical parameters of fifteen compositions of alternative fuels. The task of developing non-contact methods of fuel composition analysis is relevant. Aim of the Study. The study is aimed at obtaining dielectric constant data of alternative fuels for further search of the relationship with combustion process. Materials and Methods. For the study there was used a capacitor consisting of two 175x102 mm aluminum plates and a Sinometex ZT-Y multimeter. Results. When comparing the dielectric constant values of all presented alternative fuel compositions, there is found the dependence between the minimum and maximum content of added alcohol and vegetable oils in the mixture. This dependence manifests itself in the nature of dielectric constant values correlating with the capacitor electric capacity, if there is the mixture between the plates. It is observed for all three hydrocarbons added to the mixture: ethanol, rapeseed and colza oils. For example, the dielectric permittivity increases throughout the range from 10 to 50% of the added ethanol, rapeseed and colza oils, reaching the values from Ɛ =3.05 to 45.31; from Ɛ = 2.35 to 2.72; from Ɛ = 2.33 up to 2.8, respectively. Discussion and Conclusion. The analysis of the dielectric constant values of various alternative fuel compositions shows that when the content of alcohol and vegetable oils in the mixture increases from 10 to 50%, the dielectric constant increases. And this is true for all three hydrocarbons: ethanol, rapeseed and colza oils.

Ecofriendly ionic liquids (ILs) were synthesized through amidation of ricinoleic acid, the main fatty acid in castor oil, followed by a quaternization reaction to solubilize ethanol in IL/diesel blends at different ratios. As a result, stable and highly renewable, low viscous microemulsion biofuels with high oxygen content were prepared. The prepared fuel samples combine the advantages of green ionic liquids and microemulsion properties. The chemical structures of ILs were confirmed with the aid of NMR and FTIR spectroscopy. DLS analysis revealed that the ethanol particles ranged in size from 8 to 18.1 nm in all samples. As ILs ratios decrease in microemulsion from 37 to 69%, the ethanol particle sizes increase from 10 to 25%. Ethanol shows good solubilization in diesel and IL-1 is more effective than IL-2 in ethanol solubilization at low percentages of ethanol due to more oxygen atoms besides three hydroxyl groups. The ternary phase diagram indicated that the microemulsion area in the case of using IL-1 is larger than that of IL-2. The fuel properties of the prepared microemulsions are nearly close to those of neat diesel and fall within the permitted range of ASTM D975. The viscosity and density values at low ratios of ILs are found to be very close to the values of the neat diesel at different temperatures. The prepared samples show a slight decrease in cetane number and heating value compared to diesel. However, they have improved flash points, cloud points, sulfur content, and acid value. The particle sizes were checked every week and the prepared samples showed high stability with the aid of the synthesized ILs. Moreover, the prepared microemulsions stayed in a transparent appearance for more than a year and no phase separation was observed. [ABSTRACT FROM AUTHOR]

The Kingdom of Saudi Arabia (KSA) is facing extreme gas emissions challenges in the energy and transport sector. So, it is always preferred to use fuels that should be derived from waste to energy resources that are available abundantly without harmful environmental emissions. This experimental study uses neat diesel, and waste fat chicken oil blends to investigate the performance and emissions parameters in high-pressure common-rail multi-cylinder diesel engines. The tested fuel blends are prepared with the ratios of 10% biodiesel–diesel 90% (DB10), 15% biodiesel–diesel 85% (DB15), and 20% biodiesel–diesel 80% (DB20). The experimental results showed that, at 2000 rpm, torque and brake power produced by DB10 is 7.93% and 6.1% greater than the other diesel fuel due to its high heating value and density. The decrease in CO (16.66%), CO2 (10.79%), and HC (10.79%) emissions of DB10 compared to other diesel fuels was due to better ignition quality, higher oxygen content, and proper combustion. DB10 showed a slight increase in NOx emission (0.39%) compared to DF. Therefore, it is concluded from the performance and emission results that the DB10 is the most suitable alternative fuel compared to diesel, DB15, and DB20, and it can be used in the KSA without any modification in diesel engines. [ABSTRACT FROM AUTHOR]

Copyright of Jurnal Agroindustri Halal is the property of Universitas Djuanda and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)