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Solar Air Heaters (SAHs) are widely used to harness solar energy for various heating applications. Recent research aims to improve the ability to capture maximum irradiation, addressing the weather-dependent and intermittent nature of solar energy availability. The incorporation of Phase Change Materials (PCMs) in SAHs can improve the capacity to absorb the irradiation due to their high latent storage capacity. However, conventional PCMs often exhibit low thermal conductivity. Various enhancement techniques can improve the thermal conductivity of pure PCMs and enhance the system's performance. This review article explores single-pass and double-pass SAHs with Integrated Collector PCM Storage (IC-PCMS) systems and various techniques to enhance the thermal conductivity of PCMs. The findings are based on the detailed analysis of systems and provide quantitative results showing the performance improvements of PCM-integrated SAHs. The inclusion of PCM not only maximizes irradiation capture but also extends the duration of hot air availability during periods of uneven irradiation. Further, carbon-based nanocomposites and metal foams have shown the most significant improvements in the thermal conductivity of PCMs and thus enhance the system's performance. Future research should focus on optimization and economic analysis to commercialize these systems for various thermal applications. [ABSTRACT FROM AUTHOR]

The installed capacity of photovoltaic (PV) systems has increased significantly over the past few decades, and related technologies have advanced significantly. The electrical characteristics of a PV system change nonlinearly based on irradiation and temperature, and the I–V characteristic curve, expressed in terms of the voltage and current, is used to verify these characteristics. The maximum power point tracking (MPPT) control method was applied to maximize the performance of the PV system. Voltage and current sensors are used to control the I–V characteristic curve and MPPT; however, current sensors have various disadvantages in terms of price and system configuration. Therefore, this study presents a method for calculating the current of a PV system using the charging characteristics of a capacitor. The method presented in this paper analyzes the I–V characteristic curve's qualities through simulations and experiments under normal, shaded, and mismatched conditions of the PV module. [ABSTRACT FROM AUTHOR]

The practicality and substitutability of electric vehicles depend on there being a fast, reliable way to recharge on round trips beyond the range of a single charge. Grouping such infrastructure into charging hubs benefits developers and operators through economies of scale and electric vehicle drivers in terms of travel logistics and passed-through cost savings. The need for charging capacity at en-route charging hubs is impacted by the following four identifiable geo-social parameters: (a) highway travel volumes, reflecting the rate at which electric vehicles are expending energy in the area; (b) local population, reflecting both the increased needs of electric vehicle owners without dedicated home chargers and the reduced needs of those commuting into a metropolitan center; (c) the quantity of competing charging stations; and (d) being on a critical interprovincial route. Twelve charging stations located in diverse locations around Nova Scotia, Canada, were evaluated in terms of these four parameters, and their recorded use was investigated from a dataset of 26,000 charging events between April 2022 and April 2024. The regression reveals that there are strong positive correlations between demand for fast charging and (a) traffic volumes (45%) and (c) being on an interprovincial route (42%), while there is only a very weak correlation with (b) local population (2%). Interestingly, there is only a weak negative correlation with (c) the number and capacity of nearby competing chargers (−6%), suggesting that either in short-term route choice or longer-term vehicle choice, the presence of chargers encourages electric vehicles. [ABSTRACT FROM AUTHOR]

Solar energy is one of the major sources of renewable energy and is being extensively harnessed. However, the intermittent nature limits solar energy to act as a stand-alone energy source. Therefore, it becomes imperative that effective and economical methods of storing solar energy on a large scale are developed. Both sensible and latent heat storage methods are available. The use of a thermal energy storage (TES) system is an attractive choice for high-temperature applications such as power generation plants. The present study investigates the development of a small-scale TES system using a concentrated solar collector. For this purpose, a small cylindrical thermocline tank with suspended copper pipes in the storage medium was developed, with vegetable oil working as the heat transfer fluid (HTF) and being circulated through the pipes to transfer heat to used engine oil as the storage medium. A pump continuously circulates the HTF through the charging loop. TES was designed and developed based on the results of numerical simulations before the physical development of the experimental setup. Numerical calculations were performed for determining heat transfer and charging characteristics using different heat storage materials. The numerical results showed that a maximum temperature of 67 °C was achieved in the 100-min simulation while in the experimental results, a maximum temperature of 64 °C was achieved. The experimental results were found in close conformance with the simulation results. The experiments showed that the flow rate of 0.088 L s−1 was optimal and provided the highest temperature in the thermocline tank. The discharging experiment showed that the apparatus is viable to be used for 5.5 h for heating purposes. The salient feature of the study is an inexpensive TES system development and can act as a benchmark for the future development of renewable technology. [ABSTRACT FROM AUTHOR]

In this work, we consider a problem from the field of power-aware scheduling in which a fleet of electric vehicles have to be charged in a minimum time. Each vehicle is equipped with a lithium-ion battery of a given capacity. The initial power used for charging each battery is known, whereas it is assumed that the power drops to zero at the moment when the battery gets fully loaded. The power usage function is linear and decreasing. The charging jobs are nonpreemptable and independent, whereas the total available amount of power is limited. The objective is to minimize the schedule length. In this paper, we analyze the case of a problem with identical jobs that already cover a wide variety of practical situations. By employing inverses of natural numbers, similar to harmonic series, we prove two properties of this case, and we also discuss the phenomenon of the stabilization of the difference between the start times of two successive jobs in a schedule. We also take under examination a few special cases of the problem. Some conclusions and directions for future research are given. [ABSTRACT FROM AUTHOR]

In terms of electric vehicle architectures, the drivetrain offers unprecedented freedom, but it also creates new obstacles in terms of achieving all needs. The architecture of electric vehicles is simplified and adjustable at the component level because they don't have a combustion engine or fuel tank, only an electric motor and a battery. Implementing safe zones within electric vehicles (EVs) to accommodate battery packs necessitates significant adjustments to ensure the secure integration of the battery. A Battery EV, also known as a pure EV, solely relies on rechargeable battery packs as its source of energy, without any additional propulsion system. The Battery Management System (BMS) plays a significant role in maintaining the safety of electric vehicles by controlling the electronics of rechargeable batteries, whether they are individual cells or battery packs. The BMS plays crucial role in protecting both the user and the battery by monitoring and maintaining the cell's operation within safe limits. This research paper focuses on the control of solar‐powered charging for lithium‐ion batteries. An optimized FOPID controller is utilized to maximize power extraction from PV array and efficiently charge the battery. A hybrid optimization model is employed to optimize the gain parameters of the FOPID controller. [ABSTRACT FROM AUTHOR]

Lithium-ion battery management requires an accurate determination of the batteries’ remaining usable lives. A novel hybrid method used for the RUL and short-term capacity prediction of batteries is presented in this manuscript. The proposed technique is combined with a White Shark Optimizer (WSO) with the Multi-kernel Support Vector Machine (MSVM); therefore, it is called the WSO-MSVM technique. The major goal of this WSO-MSVM method is to attain effective future capacities and RUL forecast for the Lithium-Ion Battery (LIB) with reliable management of uncertainty. The hybrid technique solves the difficulty of forecasting the RUL of LIB. This proposal trains the WSO-MSVM model using the LIB data. The trained model is utilized to forecast the capacity and RUL of LIBs. In this proposed system, capacity, current, and voltage are considered in the discharge operation. The proposed technique validates good reliability and prediction accuracy with this suitable mechanism. Compared to the existing techniques like artificial neural network (ANN), ant lion optimizer-optimized artificial neural network, and adaptive network-based fuzzy inference system, the proposed technique shows fewer errors under charge and discharge conditions. In addition, the uncertainty intervals of the proposed WSO-MSVM technique for the predicted RUL may include the actual remaining life of the battery. The proposed technique’s charging error is lower the other exciting methods. [ABSTRACT FROM AUTHOR]

The efficient dispersion of single-walled carbon nanotubes (SWCNTs) has been the subject of extensive research over the past decade. Despite these efforts, achieving individually dispersed SWCNTs at high concentrations remains challenging. In this study, we address the limitations associated with conventional methods, such as defect formation, excessive surfactant use, and the use of corrosive solvents. Our novel dispersion method utilizes the spontaneous charging of SWCNTs in a solvated electron system created by dissolving potassium in hexamethyl phosphoramide (HMPA). The resulting charged SWCNTs (c-SWCNTs) can be directly dispersed in the charging medium using only magnetic stirring, leading to defect-free c-SWCNT dispersions with high concentrations of up to 20 mg/mL. The successful dispersion of individual c-SWCNT strands is confirmed by their liquid-crystalline behavior. Importantly, the dispersion medium for c-SWCNTs exhibits no reactivity with metals, polymers, or other organic solvents. This versatility enables a wide range of applications, including electrically conductive free-standing films produced via conventional blade coating, wet-spun fibers, membrane electrodes, thermal composites, and core-shell hybrid microparticles. [ABSTRACT FROM AUTHOR]

Most existing coal-fired power plants were designed for sustained operation at full load to maximize efficiency, reliability, and revenue, as well as to operate air pollution control devices at design conditions. Depending on plant type and design, these plants can adjust output within a fixed range in response to plant operating or market conditions. The need for flexibility driven by increased penetration of variable and non-dispatchable power generation, such as wind and solar, is shifting the traditional mission profile of thermoelectric power plants in three ways: more frequent shutdowns when market or grid conditions warrant, more aggressive load ramp rates (rate of output change), and a lower minimum sustainable load, which provides a wider operating range and helps avoid costly plant shutdowns. Recent studies have shown that the flexibility of a coal-fired power plant can be improved by energy storage. The objective of this work was to analyze a set of energy storage options and determine their impact on the flexibility and economics of a representative coal-fired power plant. The effect of three energy storage systems integrated with a coal power plant on plant flexibility and economics was investigated. The results obtained in this project show that energy storage systems integrated with a thermal power plant improve plant flexibility and participation in the energy and ancillary services markets, which improves plant financial performance. The study was funded by the U.S. Department Office of Fossil Energy FE-1 under award number DE-FE0031903. [ABSTRACT FROM AUTHOR]

Here we outline a vignette of the Bioscience Technology Facility (BTF) at the University of York as a singular exemplar of the Full Cost Recovery model. It is fully appreciated that every facility operates slightly differently, and each are subject to various rules at the institutional, regional and national level. Understanding the regulations that need to be followed for your cost recovery model may require discussion with your administrators to ensure compliance regulations for your Institution and governing bodies are followed. The below is almost a pick and mix of ways of working. It is, however, one of the few examples that is able to fully recover its operating costs within an academic environment and has sought and obtained full institutional and funders support. This model is now being much more widely adopted across the United Kingdom although again always with slightly different interpretations. [ABSTRACT FROM AUTHOR]

The heat storage system (HHS) still faces the problem of void formation as a result of the supercooling phenomenon caused by the use of paraffin. This study was conducted to analyze the effect of HTF discharge variation in the HHS system on the increase of heat storage efficiency in both the charging and discharging processes. The prototype helical coil heat exchanger is designed, fabricated, and experimentally analyzed on 4 types of helical coils with different models of fin designs: finless helical coil, straight fin, branched fin, and crossed fin. The phase change material (PCM) used is 9 kg of commercial paraffin type. The heat transfer fluid (HTF) is SAE 20W40 oil which is heated to a temperature of 210 °C with the heat source coming from the heating element. The pump is used to circulate the HTF with an output of 10 mL·s−1, 11 mL·s−1, and 12 mL·s−1. The experimental results show that the variation of the HTF flow rate affects the melting temperature, the paraffin freezing temperature, and the power efficiency of the LHS. The highest temperature absorption by paraffin was achieved by the branch fin model at 124 °C with a discharge of 11 mL·s−1, and the highest temperature release in the Branch Fin at 90 °C with a discharge of 12 mL·s−1. The highest effective power achieved by the branched fin model with effective power of 73 % charge and 53 % discharge occurred at a discharge of 12 mL·s−1. Varying the HTF discharge makes a positive contribution to the charge/discharge pattern, so it can be used as a reference for latent heat storage models. [ABSTRACT FROM AUTHOR]

One of the primary types of sensible heat storage systems in drying applications is the packed rock bed. However, to create large‐scale heat storage systems for industrial use, one must comprehend the hydrodynamic and effectiveness of the heat transport mechanism inside the bed. In this study, the thermal storage unit uses river rock as heat storage materials with equivalent particle diameters of 36 mm in bed 1 and 56 mm in bed 2. The rocks were stacked in a truncated cone‐shaped concrete wall section with an average diameter and depth of 1.1 m and 1.3 m, respectively and a volume of 2.32 m3. During the charging phase, two airflow configurations were used, one from the top with an air mass flow rate of 0.753 and 0.332 kg/m2‐s and the other from the bottom with an air mass flow rate of 0.955 kg/m2‐s. During the discharging phase, the entire flow configuration is from the bottom section. It was observed that the mass flow rate and particle equivalent diameter had an important effect on the thermal performance and behaviour of the rock bed during charging and discharging operations. Maximum efficiency was achieved with an airflow configuration provided from the bottom when charging at 0.955 kg/m2.s. Consequently, a sizable quantity of heat or energy (60 MJ) was retained. It was also observed that the relationship between air mass flow rate and particle size was significant, with smaller particles retaining more energy. When comparing bed 1 with bed 2 at this air mass flow rate, bed 1 stored 2.1 times more energy than bed 2. A wind tunnel experiment was used to measure the pressure drop in the packed rock bed. The pressure drop in the bed increases with an increase in particle Reynolds number and decreases with an increase in particle size. Rock bed heat transfer coefficient and Nusselt number were calculated using the correlation that has already been established in the literature smaller particles showed higher heat transfer coefficients and lower Nusselt numbers. This is due to the increase in particle‐to‐particle interaction and larger particle surface areas. For a given Reynolds number, the Nusselt number increases with the size of the rock particle. [ABSTRACT FROM AUTHOR]

The resonance circuit's design has a major influence on the inductive electric vehicle (EV) charging system's performance and the distance between the primary and secondary inductive coils. If resonance circuitry is not included in an inductive power transfer (IPT) system, its performance suffers dramatically and its power transfer efficiency suffers significantly. Furthermore, the design of the resonance circuit has a major impact on the rating as well as the voltage and current strains on the semiconductor switches. The sequence, amplitude, and shape of the waveform are determined by the configuration of the energy storage components. The arrangement of these components is critical in defining how the inductive power transfer system behaves and operates. A few popular architectures play an important role in shaping how the system works. In this paper, the significance and effect of resonance circuits on the inductive charging of electric vehicles have been reviewed and discussed comprehensively. Furthermore, a detailed discussion was presented for the second-order resonance circuit, the higher-order resonance circuit, and the hybrid resonance circuit. Additionally, H-bridge resonant inverter topology was discussed and three main resonant architectures for the H-bridge inverter were studied inclusively. They include the inductor-capacitor-inductor (LCL) resonance architecture, switched inductor-capacitor (SLC) resonance architecture, and High-gain resonance architecture. Also, a comparison of these architectures was done and represented in tabular form. Lastly, an analysis of the effect of frequency variations in the resonant circuit architectures. [ABSTRACT FROM AUTHOR]

Great effort is put into making our mobility system more sustainable in order to mitigate climate change. One corner stone of this endeavour is the transition from internal combustion engines to electric engines for private cars. This transition, however, introduces new challenges, especially regarding the demand for electrical energy from renewable sources. One emerging phenomenon is the so-called charging rush hour, i.e. a sharp demand spike when many people arrive home and begin charging their electric cars. In this study we use an agent-based model calibrated with empirical data on mobility behaviour to investigate strategies for mitigating this charging rush hour. Studied counter strategies include telecommuting and the possibility to charge the car at work. Our findings show that the baseline peak of 65 MW per 100 000 people can only be reduced to 55 MW per 100 000 people even when combining multiple strategies. Thus the small incentives and policy changes investigated here are not enough to solve the problem of the charging rush hour and more disruptive changes to our mobility system are required.

In this study, we introduce the water wave optimized bidirectional long short-term memory (WWO-BLSTM) model for predicting the charging usage of electric vehicles (EVs).WWO can be utilized to optimize the charging schedules of EVs, enabling the flexible change of charging patterns. The estimation of EV charging use implements BLSTM, a model that analyzes sequential data in forward and backward directions. Initially, we collected a dataset that includes 10,595 unregulated charging operations from workplace charging. This dataset represents the diversity of EV charging .A comprehensive data cleansing procedure was performed. To ensure the suggested method is effective, we employ MATLAB software to conduct simulations. This model was able to obtain a recall of 96%, F1 score of 93%, accuracy of 88% and precision of 95%. We offer outstanding outcomes for the charging consumption of EVs using our innovative WWO-BLSTM methodology.

Using Critical Race Theory and an intersectional framework, the present study focuses on the case processing of sexual assault (SA) incidents involving Black and Latina victims. Importantly, much of the prior literature assessing arrest and charging decisions have been whitewashed by failing to consider that the factors influencing the case progression of white victims' SA experiences may not appropriately apply to women of Color. Oftentimes, this scholarship merely controls for victim and suspect race without considering how legal and extralegal incident and case factors may operate differently for victims of Color. The present study addresses this oversight. [ABSTRACT FROM AUTHOR]

The demand for cooling applications increases severalfold; the integration of the CTES system will mitigate the demand and pollution caused by the building sectors. The objective of this study is to investigate the effect of grooving on the inner surface of the spherical capsule on the solidification characteristics of deionized (DI) water, which finds widespread use in the bed of cool thermal energy storage applications. Eight hemispheres made of mild steel of 100-mm diameter and 1-mm thickness are used to make four spherical capsules by the welding process for the study. Among the four capsules, one with a plain surface and the remaining with a groove depth of 0.3 mm, 0.5 mm, and 0.7 mm are made. The grooving in the hemispherical capsule is obtained by the turning operation. The experiments are conducted at various bath temperatures of − 6 °C, − 9 °C, and − 12 °C. The experimental result reveals that the surface modification leads to a significant reduction in solidification time, and in particular, the maximum percentage reduction in solidification time is achieved at − 6 °C. The provision of grooves makes the evaporator operate at − 6 °C instead of − 12 °C till the solidification of 75% mass and the predicted energy saving is 18 to 24%. As the enhancement of heat transfer rate techniques is carbon-free, the recycling of the PCM will have zero impact on environmental pollution. [ABSTRACT FROM AUTHOR]

Quantum control allows us to address the problem of engineering quantum dynamics for special purposes. While recently the field of quantum batteries has attracted much attention, optimization of their charging has not benefited from the quantum control methods. Here we fill this gap by using an optimization method. We apply for the first time the convergent iterative method for the control of the population of a bipartite quantum system in two cases, starting with a qubit-qubit case. The quantum charger-battery system is considered here, where the energy is pumped into the charger by an external classical electromagnetic field. Secondly, we systematically extend our investigation to a second case involving two harmonic oscillators in the Gaussian regime, presenting an original formulation of the method. In both cases, the charger is considered to be an open dissipative system, as its interaction with the drive may require a more pronounced exposure to general interaction with environment. A key consideration in our optimization strategy is the practical concern of turning the charging external field on and off. We find that optimizing the pulse shape yields a substantial enhancement in both the power and efficiency of the charging process compared to a sinusoidal drive. The harmonic oscillator configuration of quantum batteries is particularly intriguing, as the optimal driving pulse remains effective regardless of the environmental temperature. This study introduces a novel approach to quantum battery charging optimization, opening avenues for enhanced performance in real-world applications. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Tiangong University is the property of Journal of Tianjin Polytechnic University 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.)

With more electric vehicles introduced in society, there is a need for the further implementation of charging infrastructure. Innovation in electromobility may result in new charging and discharging strategies, including concepts such as smart charging and vehicle-to-grid. This article provides an overview of vehicle charging and discharging innovations with a cable connection. A MATLAB/Simulink model is developed to show the difference between an electric vehicle with and without the vehicle-to-grid capabilities for electricity grid prices estimated for Sweden for three different electric vehicle user profiles and four different electric vehicle models. The result includes the state-of-charge values and price estimations for the different vehicles charged with or without a bidirectional power flow to and from the electric grid. The results show that there is a greater difference in state-of-charge values over the day investigated for the electric vehicles with vehicle-to-grid capabilities than for vehicles without vehicle-to-grid capabilities. The results indicate potential economic revenues from using vehicle-to-grid if there is a significant variation in electricity prices during different hours. Therefore, the vehicle owner can potentially receive money from selling electricity to the grid while also supporting the electric grid. The study provides insights into utilizing vehicle-to-grid in society and taking steps towards its implementation. [ABSTRACT FROM AUTHOR]

In the last three decades, many researchers have published their findings on the storage of thermal energy using various phase transition materials (both organic and non-organic). One of their goals was to have a higher heat storage capacity with a shorter heat charging cycle for thermal energy storage. This study looked into a floating capsule thermal energy storage system (TESS). A number of spherical capsules filled with beeswax were placed in a paraffin-filled cylindrical shell. With heat transfer fluid flowing through three hexagonal tubes arranged at 120° inside the TESS core, the two phase change materials (beeswax with a thermal conductivity of 0.25 W/mK and paraffin with a thermal conductivity of 0.23 W/mK) were charged and discharged. For the proposed TESS, a mathematical model was created and utilised to forecast thermal energy storage capacity and charging/discharge times for various configurations. In TESS, a 70-30% mixture of the two PCMs results in a 21.5 percent increase in heat storage capacity when beeswax alone is used, and an 8.4 percent decrease in storage capacity when paraffin alone is used. For a heat storage capacity of 7300 kJ, the model estimates charging and discharging times of around 2.6 and 3.2 hours, respectively. [ABSTRACT FROM AUTHOR]

Greenhouse gas (GHG) emissions from transport contribute significantly to climate change. Some of the transport policies with the greatest potential to mitigate climate change are related to zero-emission vehicles. This study aimed to analyse the different factors, and their importance, influencing purchase decisions for battery electric vehicles (BEV). Experts' perceptions were collected with a Delphi study consisting of a two-round survey to assess factors that would increase the probability of a petrol- or diesel-car owner purchasing a BEV in Finland in the year 2025. Increasing the possibilities for home charging and the provision of a purchase subsidy were seen as the most important factors. Public fast charging and the difference in use costs between current technology vehicles and BEVs were also recognised as important factors. Existing systems of financial instruments and policies must be constantly evaluated and updated due to the evolving BEV industry. [ABSTRACT FROM AUTHOR]

The core goal of the BANULA research project is to combine customer-oriented and grid-compatible charging of electric vehicles. It addresses the current challenges of the e-mobility ecosystem from the perspective of grid operators and charging infrastructure users and creates added value for every mass market role involved. In the project, the idea of a virtual balancing group based on blockchain technology is implemented. Thereby, it enables extended data acquisition, a real-time data exchange between grid and market participants, proper balancing and grid node-specific load flow determination and, thus, load management. [ABSTRACT FROM AUTHOR]

The research work proposes an efficient Gallium Nitride (GaN) based isolated bidirectional DC-DC (IBDC)-Triple Active Bridge (TAB) based multi-port converter (MPC) for electric vehicle (EV) charging. The developed GaN IBDC-TAB based MPC utilizes fewer components compared to conventional IBDC charging system if designed for two output ports. The proposed GaN IBDC-TAB based MPC incorporates one input port, Port 1, and two output ports, Port 2 and Port 3 for Level-1 and Level-2 EV charging systems respectively. In addition, the developed GaN IBDC-TAB can be operated in Single Active Bridge (SAB), and Dual Active Bridge (DAB) modes as per operational requirements. A 12 kW GaN IBDC-TAB based MPC is designed and evaluated using LTspice XVII software. In TAB mode of operation, Port 2 delivers 1.5 kW, and Port 3 delivers 10.6 kW. The maximum efficiency of 98.87 % is obtained in simulation for the MPC converter in TAB mode. For experimental validation, an approximately 1 kW prototype is presented with Port 1, Port 2, and Port 3 voltages as 230 V, 120 V, and 200 V respectively with an operating frequency of 100 kHz. The single-phase-shift control strategy is implemented for controlling the transmitted power in the developed GaN IBDC-TAB based MPC.

The availability of low-cost unmanned aerial vehicles (UAVs), or drones, has made their organisation in fleets more feasible. The required coordination for managing these fleets comes with an increased complexity. When used for long-durability, autonomous inspection missions, it is necessary to recharge the drones due to their limited battery capacity. By providing a set of nearby charging stations, the fleets can autonomously recharge and sustain indefinite missions. In order to reduce congestion at these charging stations, effective scheduling of charging cycles can have a significant impact on the mission execution time. In this paper, we propose a novel centralized method for scheduling charging time windows, taking into account the travel distances and occupation of charging stations. We formulate a mixed-integer linear program (MILP) model with two extensions to reduce the computational complexity. The solution to this problem assigns a set of charging windows to each drone, minimizing the mission execution time and ensuring batteries will not fully deplete. The performance of our proposed method is evaluated through a series of experiments, based on a discrete-event simulator. Our results reveal a clear benefit over a greedy approach, reducing the mission execution time by up to 39.8%. Through careful parameter selection, a trade-off between mission execution time and scheduling time can be found.

The effects of Constant current- Constant voltage charging and combined sinusoidal waveform charging methods on the internal structure of LiFePO4 battery have been discussed in detail in this study. Experimental results clearly indicated that after 600 cycles, the battery that utilized the charging method had retained about 94% of state of health. In the electrochemical impedance analysis and cyclic voltammetry tests, the portion of the SEI film impedance was increased about 0.08 $\text{m}\Omega $ . In the micro structured view, no significant SEI film formation was observed on the surface of the negative electrode that used the battery in the present charging method. Finally, in the analysis of the SEI film composition, it was found that the Li2CO3 and Li2O content in the Li element was only about 15.97% and 4.42% in the battery employing this charging method, and the battery component contents in the CC-CV charging method were 27.2% and 6.69% respectively.

Greenhouse gas (GHG) emissions from transport contribute significantly to climate change. Some of the transport policies with the greatest potential to mitigate climate change are related to zero-emission vehicles. This study aimed to analyse the different factors, and their importance, influencing purchase decisions for battery electric vehicles (BEV). Experts’ perceptions were collected with a Delphi study consisting of a two-round survey to assess factors that would increase the probability of a petrol- or diesel-car owner purchasing a BEV in Finland in the year 2025. Increasing the possibilities for home charging and the provision of a purchase subsidy were seen as the most important factors. Public fast charging and the difference in use costs between current technology vehicles and BEVs were also recognised as important factors. Existing systems of financial instruments and policies must be constantly evaluated and updated due to the evolving BEV industry.

The installed capacity of photovoltaic (PV) systems has increased significantly over the past few decades, and related technologies have advanced significantly. The electrical characteristics of a PV system change nonlinearly based on irradiation and temperature, and the I–V characteristic curve, expressed in terms of the voltage and current, is used to verify these characteristics. The maximum power point tracking (MPPT) control method was applied to maximize the performance of the PV system. Voltage and current sensors are used to control the I–V characteristic curve and MPPT; however, current sensors have various disadvantages in terms of price and system configuration. Therefore, this study presents a method for calculating the current of a PV system using the charging characteristics of a capacitor. The method presented in this paper analyzes the I–V characteristic curve’s qualities through simulations and experiments under normal, shaded, and mismatched conditions of the PV module.

The practicality and substitutability of electric vehicles depend on there being a fast, reliable way to recharge on round trips beyond the range of a single charge. Grouping such infrastructure into charging hubs benefits developers and operators through economies of scale and electric vehicle drivers in terms of travel logistics and passed-through cost savings. The need for charging capacity at en-route charging hubs is impacted by the following four identifiable geo-social parameters: (a) highway travel volumes, reflecting the rate at which electric vehicles are expending energy in the area; (b) local population, reflecting both the increased needs of electric vehicle owners without dedicated home chargers and the reduced needs of those commuting into a metropolitan center; (c) the quantity of competing charging stations; and (d) being on a critical interprovincial route. Twelve charging stations located in diverse locations around Nova Scotia, Canada, were evaluated in terms of these four parameters, and their recorded use was investigated from a dataset of 26,000 charging events between April 2022 and April 2024. The regression reveals that there are strong positive correlations between demand for fast charging and (a) traffic volumes (45%) and (c) being on an interprovincial route (42%), while there is only a very weak correlation with (b) local population (2%). Interestingly, there is only a weak negative correlation with (c) the number and capacity of nearby competing chargers (−6%), suggesting that either in short-term route choice or longer-term vehicle choice, the presence of chargers encourages electric vehicles.

Wireless power transfer is a widely applied technology whose market and application areas are growing rapidly. It is considered to be a promising supplement to the conductive charging of electrical vehicles (EVs). Wireless charging provides safety, convenience, and reliability in terms of mitigating issues related to wiring, risk of tearing, trip hazards, and contact wear inherent to the conductive charging. A variety of coil structures have been researched for EV charging applications; however, most of them were of the symmetrical type. This work analyzes systems of coils possessing ferromagnetic backing with non-symmetrical geometries and compares them with the conventional symmetrical ones. Numerical FEM simulation was applied in the research. The numerical models were verified analytically and experimentally. The impact of air-gap length, longitudinal displacement, number of turns, and width of the ferrite bars on coupling factor was investigated. The results suggest that coil systems with non-symmetrical structures of ferromagnetic backings are a good alternative to the conventional symmetrical structures for wireless electrical vehicle charging applications. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny 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.)

A radical transformation of the transport industry is required in order to achieve a fossil-fuel-free vehicle fleet and reach the greenhouse gas emissions goals. Electrification plays a crucial role in this radical process. An electric road system (ERS) is a road that supplies power to electric vehicles as they drive on it, offering numerous advantages. These include an extended driving range, decreased reliance on batteries, and increased flexibility and convenience for drivers, eliminating the need to stop for recharging. This paper highlights the transformative potential of ERS in revolutionizing the land transport sector. Through thorough testing with a conductive ERS demonstrator, the viability of the presented technology is validated. Essential aspects like power transfer, efficiency, safety, and environmental impact showcase ERS's adaptability and scalability across diverse vehicle types. This study recommends widespread ERS support for battery electric vehicles, emphasizing the route toward a sustainable future. [ABSTRACT FROM AUTHOR]

In this study, we introduce the water wave optimized bidirectional long short-term memory (WWO-BLSTM) model for predicting the charging usage of electric vehicles (EVs). WWO can be utilized to optimize the charging schedules of EVs, enabling the flexible change of charging patterns. The estimation of EV charging use implements BLSTM, a model that analyzes sequential data in forward and backward directions. Initially, we collected a dataset that includes 10,595 unregulated charging operations from workplace charging. This dataset represents the diversity of EV charging. A comprehensive data cleansing procedure was performed. To ensure the suggested method is effective, we employ MATLAB software to conduct simulations. This model was able to obtain a recall of 96%, F1 score of 93%, accuracy of 88% and precision of 95%. We offer outstanding outcomes for the charging consumption of EVs using our innovative WWO-BLSTM methodology. [ABSTRACT FROM AUTHOR]

In the present study, an embedded cooling tube (ECT) type metal hydride (MH) reactor has been designed, manufactured, and tested for possible integration with a low-temperature Polymer Electrolyte Membrane Fuel Cell (LT-PEMFC) at 40–60 °C. The MH reactor filled with 21.5 kg La 0.9 Ce 0.1 Ni 5 has been subjected to a series of parametric tests. At 20 bar, 25 °C, the MH reactor absorbed 276.08 g hydrogen in 1129 s, accounting for 1.28 wt.% charged capacity. At 40 °C, the reactor desorbed 282.8 g hydrogen within 4860 s, which, if discharged through a mass flow controller (MFC) at a steady rate, could feed a 3.5 kW LT-PEMFC for the same duration maintaining the reactor pressure above 1 bar. An increase in discharging temperature to 60 °C showed about 54% increase in average hydrogen discharge rate. Influence of variation in heat transfer fluid (HTF) flow rate was discovered to be insignificant for both charging and discharging. • A large-scale metal hydride (MH) reactor was tested for integration with LT-PEMFC. • Experimentally determined optimum H 2 charging condition was 20 bar, 25 °C, 20 LPM. • Experimentally determined optimum H 2 discharge condition was 50 °C, 20 LPM. • The designed MH reactor could potentially run a 3.5 kW LT-PEMFC for 4860 s. • The estimated average heating rate required for hydrogen discharge was 0.5–0.65 kW. [ABSTRACT FROM AUTHOR]

To overcome the weak thermal conduction of the phase change materials (PCM), This investigation aims to study the effect of circular Y-shaped fins added to a two-pipe latent heat-saving unit compared with conventional circular fins. The system is placed in a straight-up orientation, and the PCM is located in the annulus, whereas hot water is moved inside the internal tube to charge the phase change material (PCM) with a phase change point of 35°C. Different independent geometric factors of the fins involving the length of the stem and angle of the tributaries to the horizontal line and the number of Y-shaped fins are analysed. The impact of the working fluid's Reynolds number and temperature (as the input parameters) are evaluated as a sensitivity analysis to control the output (melting time and rate). The results show that increasing the height and number of the fins and reducing the angles of the tributaries results in higher performance of the system. For the optimal case, increasing the Reynolds number of the working fluid from 500 to 2000 results in 31% reductions in the melting time. Moreover, raising the working fluid's temperature from 45° to 55° reduces the melting time by ~44%. [ABSTRACT FROM AUTHOR]

Interstellar dust (ISD) particles penetrate the solar system due to the relative motion of the Sun and the local interstellar cloud. Before entering the heliosphere, they pass through the heliospheric interface – the region of the solar wind interaction with the interstellar plasma. The size distribution and number density of dust grains are modified in the interface essentially. The modification depends on the charging of the dust particles along their trajectories. In this paper, we present modeling results of the charging of ISD particles passing through the heliospheric interface. The main physical processes responsible for the charging within the heliospheric conditions are the sticking of primary plasma particles, secondary electron emission, photoemission, and the effects of cosmic ray electrons. We consider two methods to calculate the electric charge of ISD particles based on (1) the classic steady-state assumption that the charge depends only on local plasma and radiation conditions and (2) the dynamical computation of charge along the particle trajectory. We demonstrate that the steady-state assumption is quite justified to model trajectories and number density distributions of relatively big ISD grains (radius of 100 nm and larger) penetrating the heliosphere. The estimates show that ISD grains of these sizes require less than 0.25 years (distance of ≈ 1 au) after transition from the LISM into the heliosphere to reach an equilibrium. For small particles (radius of 10 nm), the dynamical computation of charge influences the trajectories and modifies the number density substantially. The dust density accumulations are distributed within a more elongated region along the heliopause in case of dynamically changed charge as compared with the use of a steady-state charge approximation. As a result, the magnitudes of number density at the points of density features differ several times between the results obtained by the two considered approaches. [ABSTRACT FROM AUTHOR]

Accurately predicting the spatial distribution and charging demand of future electric vehicles is vital to directing investment in charging infrastructure and planning policy interventions. To date, this expansion has been heavily concentrated in wealthy cities and suburbs, among commuters, and among households able to charge their vehicles at home. The expansion of EV ownership will include both changes in where the vehicles are owned as well as how they are used and charged. This paper demonstrates methods to predict where the expansion of electric vehicle ownership is likeliest to occur under current market characteristics and allow for testing of scenarios of future characteristics. These methods are demonstrated with an analysis of California, using a scenario of 4 million battery electric vehicles and 1 million plug-in hybrid electric vehicles, to match the state’s goal of 5 million zero-emission vehicles by 2030. These projections are combined with a model for charging behavior to generate scenarios of demand for charging away from home under various fleet characteristics and identify areas of the state with the greatest need for infrastructure investment.

In this work, we consider a problem from the field of power-aware scheduling in which a fleet of electric vehicles have to be charged in a minimum time. Each vehicle is equipped with a lithium-ion battery of a given capacity. The initial power used for charging each battery is known, whereas it is assumed that the power drops to zero at the moment when the battery gets fully loaded. The power usage function is linear and decreasing. The charging jobs are nonpreemptable and independent, whereas the total available amount of power is limited. The objective is to minimize the schedule length. In this paper, we analyze the case of a problem with identical jobs that already cover a wide variety of practical situations. By employing inverses of natural numbers, similar to harmonic series, we prove two properties of this case, and we also discuss the phenomenon of the stabilization of the difference between the start times of two successive jobs in a schedule. We also take under examination a few special cases of the problem. Some conclusions and directions for future research are given.

The efficient dispersion of single-walled carbon nanotubes (SWCNTs) has been the subject of extensive research over the past decade. Despite these efforts, achieving individually dispersed SWCNTs at high concentrations remains challenging. In this study, we address the limitations associated with conventional methods, such as defect formation, excessive surfactant use, and the use of corrosive solvents. Our novel dispersion method utilizes the spontaneous charging of SWCNTs in a solvated electron system created by dissolving potassium in hexamethyl phosphoramide (HMPA). The resulting charged SWCNTs (c-SWCNTs) can be directly dispersed in the charging medium using only magnetic stirring, leading to defect-free c-SWCNT dispersions with high concentrations of up to 20 mg/mL. The successful dispersion of individual c-SWCNT strands is confirmed by their liquid-crystalline behavior. Importantly, the dispersion medium for c-SWCNTs exhibits no reactivity with metals, polymers, or other organic solvents. This versatility enables a wide range of applications, including electrically conductive free-standing films produced via conventional blade coating, wet-spun fibers, membrane electrodes, thermal composites, and core-shell hybrid microparticles.

Most existing coal-fired power plants were designed for sustained operation at full load to maximize efficiency, reliability, and revenue, as well as to operate air pollution control devices at design conditions. Depending on plant type and design, these plants can adjust output within a fixed range in response to plant operating or market conditions. The need for flexibility driven by increased penetration of variable and non-dispatchable power generation, such as wind and solar, is shifting the traditional mission profile of thermoelectric power plants in three ways: more frequent shutdowns when market or grid conditions warrant, more aggressive load ramp rates (rate of output change), and a lower minimum sustainable load, which provides a wider operating range and helps avoid costly plant shutdowns. Recent studies have shown that the flexibility of a coal-fired power plant can be improved by energy storage. The objective of this work was to analyze a set of energy storage options and determine their impact on the flexibility and economics of a representative coal-fired power plant. The effect of three energy storage systems integrated with a coal power plant on plant flexibility and economics was investigated. The results obtained in this project show that energy storage systems integrated with a thermal power plant improve plant flexibility and participation in the energy and ancillary services markets, which improves plant financial performance. The study was funded by the U.S. Department Office of Fossil Energy FE-1 under award number DE-FE0031903.