Green Energy Sources Research Articles

Electric propulsion for lifeboat

This paper presents the integration of the electric propulsion technology in the lifeboat maneuvering system to enhance efficiency, reliability and sustainability. The present lifeboat propulsion system often relies on the internal combustion engine which requires fuel to propel and also has various challenges to face such as emissions, maintenance, and overall environmental impact. This paper delves into the design, economics, ergonomics, engineering challenges and performance assessments associated with the successful implementation of electric propulsion for lifeboats. Special emphasis is given to the research and development of lightweight, high-capacity energy storage systems (ESS) and efficient electric motors which are suitable for the maritime emergency evacuation applications. The features of electric propulsion (EP), such as reduced harmful emissions, lowering maintenance requirements and improving maneuverability draws more attention for this research field. The paper also explores the integration of green energy sources such as solar and wind that can be used to supplement the electric propulsion system which enhance the autonomy and sustainability of the lifeboat during emergencies. This work focuses on the overall advancement of maritime emergency safety equipment and will also help in contributing to make maritime services more eco-friendly by offering a comprehensive analysis of electric propulsion integration in lifeboats, providing insights for further future developments.

Humic Acid: A Promising and Green Bioorganic Catalyst in Organic Syntheses

AbstractThe growing pollution and threat to the environment demand green synthetic methods. Green chemistry mainly focuses on minimizing the waste and utilization of green solvents, energy sources, and catalysts and prefers one‐pot reactions. In this context, humic acid (HA), a natural bioorganic catalyst found in rivers, peat coal and sewage; is a high molecular weight macromolecule containing multifunctional groups, mainly contains quinone, phenolic OH, and COOH groups which make it acidic and activate carbonyl groups by protonation. Owing to its green aspect such as biodegradability, recyclability and reusability, humic acid is considered as sustainable bioorganic catalyst which meets the criteria for industrial requirements. The HA is mild acidic in nature, thus many functional groups tolerate in the HA catalyzed reactions. After few initial reports in 2001 and 2009, the HA catalyzed reactions gained much attention by the organic synthetic community from 2019 in aldol condensation, Knoevenagel condensation, Claisen‐Schmidt reaction, Michael addition, Strecker synthesis, tetrazole synthesis, Hantzsch dihydropyridine synthesis, hydrosilylation of terminal alkenes, hydrogenation, α‐aminophosphonate synthesis, cross coupling reactions such as Heck and Suzuki coupling reactions. Herein we report the comprehensive analysis on the role of HA in organic transformations providing diverse array of molecular scaffolds till date and future perspective.

Adsorption mechanism study of sour natural gas and sulfur in high-sulfur carbonate rock gas reservoirs

As the world pivots towards green and renewable energy sources, natural gas stands out as a clean and efficient alternative. In particular, there has been an upsurge in the exploration and development of gas fields rich in hydrogen sulfide (H2S). However, an escalating issue of sulfur deposition is notably pronounced in carbonate rock reservoirs predominantly comprised of dolomite, as exemplified in China's Yuan Ba gas field. This study examines sulfur adsorption in high-sulfur gas reservoirs and its effects on carbonate rock formations. Molecular simulation analysis reveals that the sour natural gas density in 20 Å dolomite nanopore structure experiences an average increase of 30% at the nanoscale. Notably, CO2 and H2S manifested strong adsorption tendencies in smaller pore sizes, with CO2's strong adsorption state layer thickness measuring approximately 2.93 Å, and H2S's at about 1.871 Å. Additionally, it was found that the adsorption energy of sour natural gas decreases with rising temperature and pore size, and falling pressure, yet the temperature's effect on excess adsorption density is minor above 40 MPa. As the pore size reaches 160 Å, the strong adsorption states of CO2 and H2S dissipate. Beyond 160 Å, the influence of nanoscale dimensions is negligible, with only a 2.23% increase in adsorbed phase density compared to the bulk phase. The introduction of S8 molecules amplified the adsorption proclivities of CO2 and H2S, urging them closer to the pore wall. The study reveals that CO2 or H2S reinjection into formations could effectively mitigate sulfur deposition in pores smaller than 160 Å, offering valuable insights for the development of high-sulfur gas fields.

A life cycle decision framework of China offshore wind turbines with ANP-Intuitionistic fuzzy TOPSIS method

In China, offshore wind energy is a popular source of green energy. Selecting offshore wind turbine design schemes is a decision problem based on multiple criteria. However, the selection is hardly made from the point of view of the life cycle due to the complex association of evaluation criteria, especially in the conceptual design stage. To solve this problem, a new multi-criteria decision-making framework for selecting the life cycle design scheme of offshore wind turbines is designed. The design information of the life cycle process of these turbines is expressed using Function-Structure-Material-Process-Transportation model in this framework. The life cycle evaluation index system of offshore wind turbines was established and mapped with this model to carry out rapid evaluation of various schemes. In light of this, an intuitive fuzzy Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method based on analytic network process (ANP) was proposed to process fuzzy decision information and establish criteria correlation. Finally, a case study was conducted, and sensitivity and comparative analyses were carried out. The proposed method can effectively select the optimal scheme from six different design schemes for the life cycle of offshore wind turbines.

Recent advances in 2D structured materials with defect-exploiting design strategies for electrocatalysis of nitrate to ammonia

Ammonia has been used in a wide variety of applications, and with the recent interest in hydrogen energy as a green energy source, it is emerging as a cost-effective, high-density hydrogen carrier due to its three hydrogen atoms. Currently, ammonia is produced by the Haber-Bosch method at high temperatures and pressure, which is energy-intensive and emits large amounts of carbon dioxide. As a viable alternative, the electrochemical conversion of nitrate to ammonia has emerged as an efficient and eco-friendly synthesis method. To encourage further exploration in this field, this review offers insights into utilizing two-dimensional materials as electrochemical catalysts, focusing on designs that exploit defects for nitrate reduction to ammonia.

A study of the effect of cerium ion doping concentration on the structural, electrical, and thermoelectric properties of CaMnO3 nanoparticles

Abstract Universally, energy loss in the form of heat is predominant and this heat is irrecoverable waste heat that leads to global warming. Clean, green, eco-friendly, cost-effective, and renewable energy sources are the possible solutions for this energy crisis and global warming issues. Thermoelectric power generation is a promising technology by converting this irrecoverable waste heat directly into electricity without any greenhouse gas emission. Nanostructured CaMnO3 at various cerium concentrations have been successfully prepared by sol–gel hydrothermal method followed by annealing and sintering. Pure and doped samples were systematically characterized by DSC, powder XRD, RAMAN, SEM with EDAX and FTIR spectroscopy. Electrical and thermoelectrical measurements were carried out on the sintered pellets. The XRD analyses confirmed the formation of orthorhombic perovskite structure for all the samples and the average particle size lies in the range of 50–60 nm. FTIR analysis shows the presence of CaMnO3 nanoparticles without any impurities. The temperature dependence of physical properties was performed and analyzed between room temperature and 600 °C. Electrical resistivity strongly depends on the nature of substituent ions and negative values indicate that the electrons are major charge carriers. Large Seebeck coefficient value and high-power factor make Ca1−x Ce x MnO3 an efficient thermoelectric material for energy storage applications.

Synthesis of Hydrochars via Hydrothermal Carbonization of Zinc Chloride Activated Cotton Textile Waste

Anthropogenic pollution from fossil fuel combustion due to increasing global populations and emerging industries poses a serious threat to the environment. Therefore, it is vital to explore alternative green energy sources. Hence, this study synthesized renewable solid fuel hydrochars by utilizing biomass of cotton textile waste (CTW) as feedstock. ZnCl2 was selected as a catalyst due to its Lewis acid properties promoting hydrolysis and dehydration of raw materials towards hydrochar formation. The ZnCl2-activated cotton textile waste (ZnCl2-CTW) was prepared via the wet impregnation method at different ZnCl2 loading. The hydrochars were synthesized via hydrothermal carbonization of ZnCl2-CTW in a Parr batch reactor at the reaction temperature of 200 °C for 3 h. The hydrochars and CTW were characterized using a thermogravimetric analyser (TGA) to evaluate the proximate analysis, whereas an elemental analysis and determination of higher heating value (HHV) were conducted employing a CHNS analyser. The proximate analysis indicates the hydrochars volatile matter increases at higher catalyst loading, possibly due to the high content of bio-oil adsorbed on the hydrochars surface. The elemental analysis shows higher carbon and lower oxygen content for hydrochars compared to CTW, mainly due to the dehydration, decarboxylation, and aromatization reactions during HTC. Meanwhile, the HHV of hydrochars increases as catalyst loading increases to 1.5 g, which obtained the highest value of 18.41 MJ/kg, indicating good quality of solid fuel. This demonstrated that the ZnCl2 catalyst was useful in improving the energy density of hydrochars. Overall, ZnCl2 catalyst loading of 1.5 g has exhibited good performance in producing hydrochars via HTC of CTW. Thus, ZnCl2-CTW has the potential to produce hydrochar suitable as solid fuel, contributing to the conversion of waste into energy and the preservation of the environmental.

Green hydrogen energy production: current status and potential

Abstract The technique of producing hydrogen by utilizing green and renewable energy sources is called green hydrogen production. Therefore, by implementing this technique, hydrogen will become a sustainable and clean energy source by lowering greenhouse gas emissions and reducing our reliance on fossil fuels. The key benefit of producing green hydrogen by utilizing green energy is that no harmful pollutants or greenhouse gases are directly released throughout the process. Hence, to guarantee all of the environmental advantages, it is crucial to consider the entire hydrogen supply chain, involving storage, transportation and end users. Hydrogen is a promising clean energy source and targets plan pathways towards decarbonization and net-zero emissions by 2050. This paper has highlighted the techniques for generating green hydrogen that are needed for a clean environment and sustainable energy solutions. Moreover, it summarizes an overview, outlook and energy transient of green hydrogen production. Consequently, its perspective provides new insights and research directions in order to accelerate the development and identify the potential of green hydrogen production.

ZnSe-doped N-C skeleton-driven electrode for enhanced electron transport in microbial fuel cells

Microbial fuel cells (MFCs), a promising green energy source, have faced limitations in performance. To address this, we synthesized a porous Zn-Se-N-C nanomaterial with a large specific surface area and significant defect density through the utilization of metal–organic frameworks (MOFs). Surface unique topography characteristics are tuned by controlling the annealing temperature. Density functional theory (DFT) calculations confirmed that the synergistic effect of Zn and Se in ZnSe nanoparticles can significantly improve oxygen reduction reaction (ORR) electrocatalytic activity. Experimental results demonstrated that the ORR performance of Zn-Se-N-C 1000 °C catalyst is comparable to that Pt/C catalyst in both alkaline and neutral conditions, especially in alkaline media. When employed as the cathode catalyst in asymmetrical MFCs with a neutral anode and an alkaline cathode, the Zn-Se-N-C 1000 °C(cathode)-MFC system achieved an impressive output current density of 8 ± 0.2 A/m−2 and a remarkable power density of 2000 ± 30 mW m−2. Additionally, the unique pore structure of Zn-Se-N-C1000°C made it highly suitable as an anode in MFCs. The Zn-Se-N-C 1000 °C (anode)-MFC demonstrated an output current density of 7.1 ± 0.9 A/m−2 and a power density of 3000 ± 111 mW m−2.

Gym’s hybrid system for off-grid renewable energy solutions

<p>The primary objectives behind transitioning from fossil fuels to green energy sources, with a particular focus on reducing both electricity costs and carbon emissions. This transition has prompted various sectors and sports bikes, to embrace renewable energy alternatives, with a specific emphasis on technologies such as photovoltaic systems, energy storage solutions, and power generation from machines. The core subject of investigation in this paper is the application of renewable energy sources within sports bikes, with a particular emphasis on a hybrid system. This hybrid system incorporates DC/DC, AC/DC, and DC/AC converters to meet the energy requirements of the facility. The central aim of the research is to identify the most economically efficient scale for a self-sufficient hybrid photovoltaic system that integrates stationary generators and battery storage. The research seeks to optimize the balance between cost-effectiveness and sustainable energy provision in the context of sports facilities.</p>

Effect of Photoanode Process Sequence on Efficiency of Dye-Sensitized Solar Cells

Owing to its contribution to carbon emission reduction, green energy has received widespread attention. Among green energy sources, solar energy is regarded as the most important. In solar energy production, dye-sensitized solar cells (DSSCs) have been favored owing to their characteristics of simple manufacturing and high efficiency as a third-generation solar cell technology. DSSCs are prospective candidates for powering indoor Internet of Things (IoT) devices. In this study, to find a method to enhance DSSCs’ efficiency, the advantages and disadvantages of the screen printing method and the mechanical pressing and annealing method were analyzed. Using an improved method, a TiO2 photoanode was processed and annealed, and the DSSCs with the photoanode showed an efficiency increase from 1.10 to 4.78%.

A Techno-Economic-Environmental Feasibility Study of Residential Solar Photovoltaic/Biomass Power Generation for Rural Electrification: A Real Case Study

To avert climate change, there has been a rise in the usage of green energy sources that are also beneficial to the environment. To generate sustainable energy in a financially and technically efficient manner, our research attempts to close the gaps. The potential of green sources like photovoltaic (PV) and biomass for a rural community southwest of Sohag Al Gadida City, Sohag, Egypt, is examined in this research considering its techno-economic (TE) and eco-friendly feasibility. The HOMER Pro v3.14 package is used as a scaling and optimization instrument, to calculate the price of the PV/biomass setup and the size and characteristics of its parts. This is to estimate the corresponding electrical production and reduce the total annual cost for the customer. The suggested system structure is validated through the presentation of simulation outcomes and evaluations utilizing MATLAB/SIMULINK R2022a. In addition, a TE-environmental investigation of the optimized PV/biomass structure is performed. The optimum structure is carefully chosen from the best four configurations using the demand predilection by analogy to the perfect technique based on the generation cost, operation cost, energy production, and renewable fraction. The results also indicate that using hybrid PV/biomass is an attractive choice with the initial capital cost (ICC: USD 8.144), net present cost (NPC: USD 11,026), a low cost of energy (LCOE: 0.184 USD/kWh), and the high renewable fraction (RF: 99.9%) of the system. The annual CO2 emission performance of a PV/biomass system is much better than that of the grid alone and PV/diesel. This method might be applied in rural areas in other developing countries.

A System and Method for Retrieving Energy Potential through Irrigation Gate of an Agricultural Dependent Hydro Power Plant

The modern economics depends on the electrical energy and the share of decarburized electrical energy is the base of 2050 net zero emission targets. Non-fossil fuel and fossil fuel energy resources are the integral part of net zero energy system. The net zero emission activities are affected by increasing demand of electricity and its related CO2 emission in 2021. The contribution of 41.4% of renewable energy as compared to 56.8% of non-renewable energy in the year of 2023 at national level necessities attention of green sources of energy like solar, wind, hydro, waste to energy, small hydropower, etc. Hydropower is one of the reliable backbones of clean energy system which should be used effectively for power generation. The turbine dependent hydropower plant of 45-60 years old requires renovation, modernization, uprating and digitization (RMUD) to resolve socio-economic concerns and increasing demands. This scenario imposes the need of finding solution in existing hydropower plant than investing on new unit. Both high and low discharge should be potentially used for power generation to improve the capacity factor of the plant. Therefore, present work focusses on improving capacity factor of an existing agricultural dependent hydro power plants having reaction type turbine. Reaction turbines operates at high flow and low/medium head conditions. The operational conditions of low flow and low head for reaction turbines may lead to noise, vibration and directed to major catastrophic failure of turbines. There is a need of utilizing the energy potentials balancing power generation and irrigation even during low flow releases. Thus, this paper is an attempt to a design and develop a modified irrigation gate with sliding gate and mini hydropower system at the inlet of existing irrigation diversion gate. Stochastic nature of flows through different hydraulic structures is to be addressed by this modification. A case study of an irrigation dependent hydropower plant Dhom (2X1 MW), MAHAGENCO, Satara, Maharashtra having TWO irrigation gates have been considered. In addition to 2MW, the suggested design can generate 680kW by average irrigation releases of 2.47m3/sec through each gate. The suggested model can be used on any hydropower plant and canal locations.

A systems approach to hazard identification for solar-powered and wave-propelled unmanned surface vehicle

Decarbonization is a trend in the maritime industry and may include the use of alternative energy sources on ships. At the same time, autonomous ships are under development. In the future, the two technologies may be combined. The objective of this study is to identify possible hazards related to the operation of autonomous vessels using green energy sources. An extended and holistic Systems-Theoretic Process Analysis (STPA) based approach is proposed, where both safety and security is considered. Changes in level of autonomy during operation are considered, and an extension of the STPA method is proposed to highlight the interaction between the system and external energy source. A solar-powered and wave-propelled unmanned surface vehicle is analysed. The results show that mission performance may be affected by both safety and security issues, and that considering influences from the environment and the autonomous functionalities of the system together, contributes to identifying hazards. The results are compared to operational experience from multiple field campaigns. The case study focuses on a relatively simple autonomous vehicle, but some functionalities may be shared with Maritime Autonomous Surface Ships (MASS). Hence, implications for utilisation of alternative energy sources on MASS, and effects on risks, are discussed.

An Improved Self-Adaptive Flower Pollination-Backpropagation Neural Network for the State of Charge Estimation of Lithium-Ion Batteries with Output Sliding Average Window Strategy

With the rapid development of electric vehicles and green energy sources, the use of backpropagation neural network (BPNN) to precisely estimate the state of charge (SOC) in lithium-ion batteries has become a popular research topic. However, traditionally BPNN has low prediction accuracy and large output fluctuations. To address the shortcomings of BPNN, self-adaptive flower pollination algorithm (SFPA) was proposed to optimize the initial weights and thresholds of BPNN, and an output sliding average window (OSAW) strategy is proposed to smooth SOC outputs in this research, which SOC estimation method is named SFPA-BP-OSAW. In addition, the performance of the newly proposed method is compared with other common related algorithms under different working conditions to verify the effectiveness of SFPA-BP-OSAW. The experimental results show that the mean absolute error of SFPA-BP-OSAW is 0.771% and 0.897%, and the root mean square error is 0.236% and 0.37%, respectively, under HPPC and BBDST working conditions. Experimental data and error analysis show that the method proposed in this paper has fast convergence, high prediction accuracy, and curve smoothness.

Assessing and prioritizing drivers and strategies for transition to a green energy for sustainable development in China

This study addresses the critical global challenge of climate change, primarily caused by the overconsumption of fossil fuels. Recognizing the urgent need for a transition to green energy (GE) sources such as wind, solar, hydro, and biomass, this research focuses on identifying effective strategies for fostering a sustainable and low-carbon energy future in China. The study employs a combination of the Analytical Hierarchy Process (AHP) and fuzzy Decision-making Trial and Evaluation Laboratory (DEMATEL), both well-established multi-criteria decision-making (MCDM) methods, to analyze various drivers, sub-drivers, and strategies crucial for this transition. Through an extensive literature review, we identified several key drivers and strategies aiding the shift towards GE for sustainable development. The AHP method was applied to evaluate and rank the major drivers and sub-drivers, such as policy, financing, and infrastructure and innovation, that are crucial for China's successful transition to GE. Simultaneously, fuzzy DEMATEL was utilized to prioritize vital strategies, including public awareness and education, financial incentives and support mechanisms, and policy and regulatory frameworks. The findings reveal that, in addition to strong policy and financial support, public awareness and education are critical for advancing GE development in China. This study underscores the importance of integrating various drivers and strategies for effective green energy development, aiming to mitigate the environmental impacts of fossil fuel use.

Optimal scheduling of a township integrated-energy system using the adjustable heat-electricity ratio model

With the expansion and implementation of rural revitalization strategies, there is a constant need for new energy sources for the construction of new townships. Consequently, integrated energy systems with the interconnection and interaction of multiple energy sources are developing rapidly. Biomass energy, a renewable green energy source with low pollution and wide distribution, has significant application potential in integrated energy systems. Considering the application of biomass energy in townships, this study established an integrated biomass energy system and proposed a model to optimize its operation. Lowest economic cost and highest clean energy utilization rate were considered as the objective functions. In addition, a plan was suggested to adjust the heat-electricity ratio based on the characteristics of the combined heat and power of the biomass. Finally, a simulation analysis conducted for a town in China was discussed, demonstrating that the construction of a township integrated-energy system and the use of biomass can significantly reduce operating costs and improve the energy utilization rate. Moreover, by adjusting the heat-electricity ratio, the economic cost was further reduced by 6.70%, whereas the clean energy utilization rate was increased by 5.14%.

Integrasi Bioenergi dalam Desain Taman Kota

Bioenergy is a renewable energy source that can be renewed naturally and has a good environmental impact on air quality in urban environments. Urban parks have the potential to integrate bioenergy into an urban context. Design environmentally friendly city parks to be able to produce bioenergy, so that public spaces can double as both open recreation spaces and sources of green energy. The air condition in Lhokseumawe City experiences CO2 pollution and high air temperatures. The aim is to implement bioenergy in gardens through application to plants and trees. Climate change is characterized by extreme rainfall and temperatures. Apart from that, the depletion of the ozone layer is the impact of global warming which is indicated by high air temperatures a global issue. In essence, climate change occurs in all cities. Apart from that, rapid urban development is the influence of the activity and density of the city center which triggers an increase in global warnings and has an impact on thermal comfort. good air quality and thermal conditions in outdoor spaces in urban areas are difficult to find. The presence of public space plays a role as a green open space and a source of green energy and renewable energy and can increase absorption areas. However, the existence of environmentally friendly green open spaces that are capable of reducing global warming cannot be integrated with bioenergy, which is still less familiar and not yet optimal for application, so it is the basic fundamental phenomenon in this research. This research aims to identify thermal quality (CO2, temperature, and wind speed); identify softcape elements, namely plants in RTH, and contribute through integration with the bioenergy approach in RTH as a solution to reduce global warming, especially CO2. This type of research is descriptive using a quantitative approach. The research results show that CO2 levels have exceeded the threshold, resulting in air pollution with high air temperatures. This condition has a very negative impact on the survival of an urban environmental climate. The presence of plant elements as softcap elements has yet to be fulfilled, so certain plants are needed as a solution in producing bioenergy applications.

A Multi Objective Multi-Stage Particle Swarm Optimization MOPSO Search Scheme for Power Quality and Loss Reduction on Radial Distribution System

There is an increasing interest in renewable and green energy sources and the integration of Distributed Generation DG into the power grid system. The problem of optimal capacitor allocation in electric distribution systems involves maximizing energy utilization, feeder loss reduction, and power factor correction. The feeder loss can be separated into two parts based on the active and reactive power loss components. The paper presents a novel method for minimizing the loss associated with the reactive component of branch currents by placing shunt capacitor optimally selected banks. This paper presents a novel technique for capacitor sizing using the Multi objective multi-stage Particle Swarm Optimization MOPSO to determine optimal capacitor sizes in a radial distribution system. The main objective functions are: 1. Minimize the feeder current for feeder loss reduction, 2. Minimum voltage deviation at each bus of the distribution system, and 3. Feeder capacity release

Does environmental policy stringency reduce trade in energy resources? Insights from coal, petroleum, and gas

Stringent Environmental policies are widely acknowledged as a significant policy option to control the harmful effects of environmental degradation. Restricting trade in energy commodities helps reduce the consumption of fossil fuels and thus improve environmental quality. Within the framework of new trade theory, the analysis intends to investigate the influence of environmental policy stringency on trade in conventional energy commodities (coal, petroleum, and gas) in the top polluted economies of the world from 1991 to 2021. Additionally, the study uses the asymmetry assumption compared to earlier research. For empirical investigation, the analysis applied the novel nonlinear CS-ARDL model that can deal with the issue of cross-sectional dependence and provide robust short and long-run estimates. Findings of the nonlinear model suggest that a positive shock in environmental policy stringency restricts trade in energy commodities in the long run, whereas a negative shock in environmental policy stringency does not exert any noticeable effect on these commodities. In the short run, a positive shock in environmental policy stringency exhibits significantly negative effects in mostly energy commodities. Energy demand and financial development promote trade in energy commodities in the nonlinear model, and the real exchange rate restricts trade in these commodities. Thus, policymakers should introduce strict environmental policies to limit the consumption of fossil fuels and promote clean and green energy sources and sustainable development.