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The wide adoption of electric vehicles (EVs) is required for deep decarbonisation of transportation sector. The lithium-ion batteries that power EVs are temperature sensitive and electric ranges reduce under cold weather conditions due to excessive need for heating the battery and the driver’s cabin. Therefore, some drivers may need to charge more often during the same day. In this paper, probabilistic modelling and simulation of large-collections of EV charging are presented and the impacts on power generation portfolio is investigated for the case of the UK. Particularly, the extra energy and power demands are quantified across different regions. Extensive simulations reveal that cold weather necessities an additional 630 MW of peak power when compared to optimal ambient temperatures. Simulation results further show that the hourly carbon intensity of the power grids could increase by 25% during cold days with low renewable generation. The problems pertinent to temperature effects on EV charging require greater attention as EVs are becoming the main mode of transport in the next decade.

Globally, Internal combustion (IC) engine-based vehicles are being replaced by electric vehicles to decrease fossil fuel depletion, pollution, and the effects of global warming. But in electric vehicles, the primary concerns are battery power consumption and battery life, which affects the range of the electric vehicle (EV). In this paper, a hybrid storage system comprising a battery and a supercapacitor is simulated in MATLAB software to enhance the range, duration, and performance of the EV by controlling the charging and discharging of the supercapacitor and battery and control logic is used to integrate a li-ion battery with a supercapacitor based on the state of charging of the battery and supercapacitor. with the use of a hybrid energy storage system, the range and performance of EVs has improved. [ABSTRACT FROM AUTHOR]

The groundbreaking Unmanned Aerial Vehicles (UAVs) technology has gained significant attention from both academia and industrial experts due to several applications, such as military missions, power lines inspection, precision agriculture, remote sensing, delivery services, traffic monitoring and many more. UAVs are expected to become a mainstream delivery element by 2040 to address the ever-increasing demand for delivery services. Similarly, UAV-assisted monitoring approaches will automate the inspection process, lowering mission costs, increasing access to remote locations and saving time and energy. Despite the fact that unmanned aerial vehicles (UAVs) are gaining popularity in both military and civilian applications, they have a number of limitations and critical problems that must be addressed in order for missions to be effective. One of the most difficult and time-consuming tasks is charging UAVs. UAVs' mission length and travel distance are constrained by their low battery endurance. There is a need to study multi-UAV charging systems to overcome battery capacity limitations, allowing UAVs to be used for a variety of services while saving time and human resources. Wired and Wireless Power Transfer (WPT) systems have emerged as viable options to successfully solve this difficulty. In the past, several research surveys have focused on crucial aspects of wireless UAV charging. In this review, we have also examined the most emerging charging techniques for UAVs such as laser power transfer (LPT), distributed laser charging (DLC), simultaneous wireless information and power transfer (SWIPT) and simultaneous light wave information and power transfer (SLIPT). The classification and types of UAVs, as well as various battery charging methods, are all discussed in this paper. We've also addressed a number of difficulties and solutions for safe operation. In the final section, we have briefly discussed future research directions. [ABSTRACT FROM AUTHOR]

Renewable energy is a type of energy that may be produced from a variety of resources, including sunlight, wind, tides, geothermal, etc. It delivers sustainable, clean energy that is derived from renewable natural resources. More renewable energy will be used, which will reduce the cost and demand for fossil fuels. The primary uses of solar photovoltaic energy include the production of electricity and heat for a variety of appliances. The development of solar-powered cars was made possible by recent breakthroughs. This study discusses the design and development of a charge controller-based solar charging system for electric automobiles. The suggested system's implementation will lower the price of power and charging and discharging losses. Additionally, one of the suggested solar charging systems is among the steps taken to create a green campus. This paper will show how to create a solar-powered electrical vehicle system and analyzes its performance. [ABSTRACT FROM AUTHOR]

The solution to the second-order unsteady partial differential one-dimensional Boussinesq equation is examined. The physical problem concerns unsteady flow in a semi-infinite unconfined aquifer bordering a lake. Two cases are examined: In the first case, a sudden rise and subsequent stabilization in the water level of the lake occurs, thus the aquifer is recharging from the lake. In the second-case, the lake sustains a surface drop, and the aquifer is discharging to the lake. In the first part of the article a new analytical Wiedeburg's transformed method for the solution of the one-dimensional Boussinesq equation is presented, for both recharging and discharging of a homogeneous unconfined aquifer. The solution is presented by a simple algebraic equation, transformed into a fourth-degree polynomial approximation for the head profiles. Additionally new formulas for recharged and discharged stored volumes are presented. Subsequently some applications are presented with profiles and stored volume, compared to other analytical solution. This extremely simple solution was proved to be very accurate in comparison to other analytical solutions in existence. [ABSTRACT FROM AUTHOR]

Climate change, global warming, pollution, and energy crisis are the major growing concerns of this era, which have initiated the electrification of transport. The electrification of roadway transport has the potential to drastically reduce pollution and the growing demand for energy and to increase the load demand of the power grid, thereby giving a rise to technological and commercial challenges. Thus, charging load prediction is a crucial and demanding issue for maintaining the security and stability of power systems. During recent years, random forest has gained a lot of popularity as a powerful machine learning technique for classification as well as regression analysis. This work develops a random forest (RF)-based approach for predicting charging demand. The proposed method is validated for the prediction of public e-bus charging demand in the city of Helsinki, Finland. The simulation results demonstrate the effectiveness of our scheme. [ABSTRACT FROM AUTHOR]

The present work presents a comprehensive state‐of‐the‐art bibliographical review of standards related to utility grid integration and best practices of the electric vehicle (EV) charging stations. The presence of a robust tuning method is essential for successful utility grid integration with the charging stations. The lack of system standardization may hamper the EV uptake as well as successful utility grid integration with the charging stations. The distributed energy resources (DER) and vehicle to grid (V2G) are going to play a vital role in the power system operation and control. The applicability of criterions within the utility grid integration with charging station area is important to the grid operators, charging service providers, manufacturers, fleet operators, and so forth to ensure safety, dependability, and interoperability. Hence, this work tries to deliver a comprehensive and systematic review of standards and best practices for utility grid interaction with charging stations. It will help the specialists of power as well as transport sectors to track down every one of the norms and best practices, which are accessible at one stage to compare different guidelines. This article is categorized under:Energy Infrastructure > Systems and InfrastructureWind Power > Systems and InfrastructureFossil Fuels > Economics and PolicyFossil Fuels > Systems and Infrastructure [ABSTRACT FROM AUTHOR]

This paper studies the problem of coordinated rebalancing and charging scheduling for mobility-on-demand systems with electric vehicles. A joint framework consisting of multi-server M/M/s queueing and fluid model is proposed to solve the problem, in which the former is used to deal with charging scheduling of vehicles, while the latter describes the dynamics of vehicles and users in the system. A fluid policy is presented to minimize the total number of in-transit empty vehicles under static equilibrium, yielding the optimal assignment by nonlinear programming. To cope with dynamically varying traffic conditions, we further develop a two-stage real-time policy for charging and rebalancing scheduling, where rebalancing assignment is periodically adjusted and a time-weighted averaging method is proposed to predict the future travel demand. Also, the amount of vehicles to be deployed in each charging station is given to minimize the customer waiting time for charging. The effectiveness of the proposed method is verified via simulations and experiments. [ABSTRACT FROM AUTHOR]

Electric vehicles (EVs) are gaining widespread adoption, which requires expanding the charging infrastructure. This infrastructure is part of a complex ecosystem that consists of multiple entities interacting with each other and exchanging (often personal) user data. Such a heterogeneous system with multiple participants exchanging personal data poses severe privacy risks to users. State-of-the-art literature insufficiently covers privacy aspects of charging ecosystem use cases. In this paper, a profound analysis of this ecosystem with respect to privacy is provided: First, the EV charging ecosystem and its entities are defined. Second, high-level use cases for EV charging identified in literature are analyzed and used for defining data flows within the charging ecosystem. Third, the identified use cases are compared in terms of privacy guarantees and adherence to standards. Fourth, representative implementations of these use cases are evaluated, i.e., all actors and (unintended) data flows are described and potential privacy threats are identified and visualized. It is found that privacy is not sufficiently covered by standards and implementations of EV charging use cases from literature. Furthermore, recommendations and future directions for protecting user privacy in the EV charging ecosystem are derived. In summary, stricter adherence to standards and privacy by design are suggested. [ABSTRACT FROM AUTHOR]

Electric vehicles are becoming increasingly popular in societies and an important part of smart grids. Utility companies should be able to provide them with vital energy as they need electric energy instead of fuel, and this is where new challenges emerge in the network. In order to avoid causing utilities to incur additional energy and economic losses, researchers have proposed smart charging as a way to provide adequate energy to vehicles. When developing a charging schedule for a fleet of EVs, special considerations are made on variables such as energy, cost, and EVs milage. In this review paper, the importance of EVs integration into smart grids is studied, and then different methods to develop EVs charging scheduling are investigated. These methods can vary from optimization algorithms to learning-based, and game theory-based approaches. Then, as the considered system consists of three main actors, including EV users, the utility operator, and aggregators, a systematic review is conducted on these actors, and objectives related to each one are analyzed. Finally, research gaps related to the problem are studied. Researchers can use this review to conduct further research on the integration of EVs into smart grids. [ABSTRACT FROM AUTHOR]

Fast charging of lithium-ion batteries is often related to accelerated cell degradation due to lithium-plating on the negative electrode. In this contribution, an advanced electrode equivalent circuit model is used in order to simulate fast-charging strategies without lithium-plating. A novel parameterization approach based on 3-electrode cell measurements is developed, which enables precise simulation fidelity. An optimized fast-charging strategy without evoking lithium-plating was simulated that lasted about 29 min for a 0–80% state of charge. This variable current strategy was compared in experiments to a conventional constant-current–constant-voltage fast-charging strategy that lasted 20 min. The experiments showed that the optimized strategy prevented lithium-plating and led to a 2% capacity fade every 100 fast-charging cycles. In contrast, the conventional strategy led to lithium-plating, about 20% capacity fade after 100 fast-charging cycles and the fast-charging duration extended from 20 min to over 30 min due to increased cell resistances. The duration of the optimized fast charging was constant at 29 min, even after 300 cycles. The developed methods are suitable to be applied for any given lithium-ion battery configuration in order to determine the maximum fast-charging capability while ensuring safe and durable cycling conditions. [ABSTRACT FROM AUTHOR]

To realize the real-time prediction of slag composition in the smelting process and provide the assistance to the operations in electric arc furnace (EAF) steelmaking process such as charging, the influence factors on the slag composition in the furnace (furnace reaction, charging, and slag overflowing) were studied, and the real-time prediction model of slag composition in EAF steelmaking process was established. In the results, the model could predict the slag quality, the slag composition, and the oxidation status of Fe element in the furnace in real time, providing the guidance for the auxiliary material charging and the slag flowing in the smelting process. Compared with the slag sampling results, the average relative errors of CaO, SiO2, and FeO content in the slag between the actual measurement and the model predicted values were 12.66%, 11.17%, and 19.16%, respectively.

The Internet of things (IoT) era needs to realize the wide coverage and connections for the IoT nodes.However,the IoT communication technology cannot collect data timely in the remote area.UAV has been widely used in the IoT wireless sensor network for the data collection due to its flexibility and mobility.The trajectory design of the UAV assisted sensor network data acquisition was discussed in the proposed scheme,as well as the UAV charging demand in the data collection process was met.Specifically,based on the hierarchical reinforcement learning with the temporal abstraction,a novel option-DQN (option-deep Q-learning) algorithm targeted for the discrete action was proposed to improve the performance of the data collection and trajectory design,and control the UAV to recharge in time to ensure its normal flight.The simulation results show that the training rewards and speed of the proposed method are much better than the conventional DQN (deep Q-learning) algorithm.Besides,the proposed algorithm can guarantee the sufficient power supply of UAV by controlling it to recharge timely.

Electrostatic forces cause spontaneous movement of charged particles; subsequently, electrostatic technology is attracting attention because of its application in powder handling processes, such as separation, classification, dispersion, and collection. Dielectric and conductive particles are charged by induction in a strong electric field and moved by Coulomb forces. The magnitude and polarity of the transferred charges are controlled by the strength and direction of the electric field. The dielectric particles are also polarized in the electric field, and dipole interactions occur between particles or in the particle layers, complicating the particle behavior. This review paper presents induction charging, agglomeration, levitation, and other behaviors resulting from particle layers in electric fields. A series of particle phenomena occur in parallel electrode systems, which consist of a lower plate electrode and an upper mesh electrode. Charged agglomerates are formed on the particle layers, levitated by the Coulomb forces, and disintegrated with rotation when approaching the mesh electrode. The mechanisms of agglomeration and disintegration have been elucidated in multiple studies, including microscopic observations and theoretical analyses of particle motion, based on numerical calculations of the electric field. Furthermore, a new system is proposed for continuous feeding of dispersed particles using electric fields and vibration.

Design of battery charging system on solar tracker based PV system and its application has been presented in this paper. To improve the system performance, a solar tracking system as an innovative device of PV has been developed with an intelligent controller. PV equipped by solar tracker can significantly enhace its performance up to 40% of conventional system. In this research solar tracker designed has active tracking mode with double axis. In order to keep the PV performance optimum, a smart battery charging system has been developed and provided to store the electricity generated by PV system. A novel algorithm was implemented to the system which allows the battery charging process to operate quickly and safely. Besides, the components involved in the system are DC-DC converter, sensor, actuator and battery. DC-DC Converter used is Single Ended Primary Inductance Mode (SEPIM) with MOSFET as its actuator. Battery charging system has used intelligent control based on fuzzy-PSO algorithm. In this case, PSO functions to optimize and modify fuzzy parameters to obtain the best model. Optimized fuzzy controller has then been implemented and programmed in an Arduino microcontroller module to generate control signal which commands actuator element to control the voltage of battery through duty cycle manipulation variable. This algorithm has been able to improve the solar charging controller significantly and more convincingly increase PV performance.

In order to bridge the gap between academia and industry in the development of cathode active material for high-energy lithium-ion batteries (LIBs), several experimental factors reflecting commercial use need to be considered. Herein, based on a thick commercial level NMC811 electrode, we simply demonstrated the effect of charging protocols on the rate performance, cycling stability, and Li storage mechanism. A constant current charge/discharge, typically used in most publications, was found to exhibit worse rate capability and cycling stability compared to the constant current constant voltage (CCCV) mode of charge, used in commercial LIB cells due to the less uniform Li concentration gradient between the surface and bulk of the material. In operando XRD also revealed that there was no negative impact from the rapid change in lattice parameters towards cycling performance. We also found that the major degradation mechanism of Ni-rich NMC811 showing poor cycling performance across literature, can be mainly ascribed to the thick cathode electrolyte interphase (CEI) resistive layer, hindering Li intercalation at high rate and also lead to lower accessible capacity in each cycle. This work illustrates a simple example of the gaps between research in academic and industry that need to be narrowed for the development of practical high energy materials.

Lithium-ion batteries are seen as a key element in reducing global greenhouse gas emissions from the transport and energy sectors. However, efforts are still needed to minimize their environmental impact. This article presents a path towards a circular economy and more sustainable batteries, thanks to their reuse in mobile charging stations for electric vehicles. This work presents the results of characterization tests and modeling of second life batteries. The presented characterization test and electrical models can be used as references to evaluate the performance of aged batteries after their first life. Detailed test procedures and data results are provided in an open-access data paper.

Solution grown quantum dots (QD) are promising materials for photonic quantum science. These materials are strongly confined and further offer advantages in terms of customizability and scalability. In this review we describe the applications of these materials towards quantum science particularly as single photon emitters. We further compare the progress made towards realizing and functionalizing these materials with the current state of the art in epitaxially grown QDs. We particularly focus on charge injection to regulate electronic energy levels and optical emission, as well as effects of strain that are crucial for quantum information applications. This suggests several potential areas where the physical properties of these materials need to be better understood and controlled to fully realize their potential in quantum science. This article thus summarizes the state of the art in terms of solution grown QD development for quantum science and also outlines key areas where progress is expected before these materials become as developed as their solid-state counterparts., (© 2024 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.)

The modular multilevel converter with embedded batteries is a viable alternative in electric vehicle drive systems. This research investigates integrated charging of the embedded batteries in a three-phase converter from a single-phase source without any additional hardware requirements. Two phases of the converter are connected to the supply while the third converter leg is not connected. In a typical charging of the converter batteries, the batteries with a lower state of charge are prioritised. Then all batteries are balanced at an average global state of charge. This research proposes a new sorting algorithm of the converter batteries with an override capability to bypass any individual submodule if required. This bypassing capability is modulation method independent, thus can be integrated with any modulation method. Simulation results and a real-time emulation of the charging system validate the proposed control method and the override algorithm. In addition, an open-loop switching technique is integrated with a new nearest level control-based measurement method of the battery terminal voltage to estimate its initial state of charge. This measurement facilitates a reduced number of voltage sensors for hardware implementation. This method was simulated and validated by comparing the calculated and the measured values of the battery initial state of charge. Real-time emulation of the system utilising hardware-in-the-loop apparatus was carried out, which confirmed the developed control system functions as expected. [ABSTRACT FROM AUTHOR]

Since battery electric vehicle (BEV) sales are increasing, the calculation of necessary electric power supply, and energy consumption data, and vehicle range is important. The Worldwide harmonized Light vehicles Test Procedure (WLTP) currently in use can deliver data to collect comparable energy consumption data for different vehicles on defined chassis dynamometer test cycles. Nevertheless, the energy consumption and so the range of BEVs are also dependent on the individual trajectory of the user. Therefore, five velocity profiles are developed in this work. The maximum speeds are based on typical velocities in German city traffic and extra-urban traffic. The energy required to finish a single velocity profile is assumed to be constant despite varying maximum velocities. With this kind of driving profiles it is possible to create an individual and more precise statement on the energy consumption and the range of a BEV. In this work, the profiles are driven on a chassis dynamometer with an VW e-Up. The vehicle charging efficiency is tested with two different AC charging modes and is also taken into account. The drive efficiencies of the tested vehicle are presented in dependence of the velocity profile driven. Finally the results are compared with a real-driving velocity profile and the energy consumption data obtained by the board computer of the vehicle. [ABSTRACT FROM AUTHOR]

A novel solar air heater design is proposed in the present study. The new design is a closed collector – storage solar air heater system (CCSSAHS) integrated with an internal finned heat exchanger filled with PCM. Two identical solar air heaters were manufactured for the sake of comparison. The first one was filled with RT42, and the second one was filled with RT50. The thermal performance of the solar air heaters was studied for RT42 and RT50, utilizing reflecting mirror; air mass flow rate, that is, 0.25, 0.045, and 0.065 kg/s; series and separation arrangements. For RT42, the experiments showed at 0.025 kg, with mirror, and series arrangement that the stored power, charging efficiency, discharged power, and discharging efficiency were 1255 W, 90.7%, 420 W, and 93.9%, respectively, while for RT50 were 1203 W, 87%, 332 W, and 88.1%, respectively. The highest air temperature difference between the exit and entrance of the solar air heater was found for RT42 at 0.025 kg/s with mirror for the separation arrangement, that is, 16.8°C. In addition, an economic evaluation was presented. CCSSAHS can satisfy tremendous industrial and domestic needs. The internal finned heat exchanger, the core component of the solar air heater, can be recycled from damaged air condition devices. The present proposed design combines the principle of recycling and clean energy to preserve the environment. [ABSTRACT FROM AUTHOR]

The paper deals with the decision-making process of the electric vehicle (EV) owners at the charging station. Firstly, the paper presents a theoretical basis for the definition of discrete choice systems. Consequently, the process of the stated preference survey design, used to obtain data about the EV owners' decisions at the charging station, is presented. The SP survey consisted of 18 hypothetical scenarios and socio-demographic questions. The SP survey was carried out from July 2020 to October 2020, and 289 residents of Slovakia with an age higher than 18 (the threshold necessary for a driving license) have taken part. This results in a sample of 5192 different responses. Based on the obtained data, the EV owners' behavior prediction model is defined and its parameters are estimated using the maximum likelihood estimation method and 90% of the sample data. Furthermore, the presented model is validated with the rest of the sample data and recommendations for future work are defined. [ABSTRACT FROM AUTHOR]

Wireless power transfer (WPT) is emerging as the preeminent way to charge electric vehicles, but there appears to be no fair way to measure the power transfer. In this article, Faraday coil transfer-power measurement (FC-TPM) is presented. FC-TPM employs non-contact, open-circuited sense coils to measure the electromagnetic field from WPT and calculates the real power propagating through the air gap between the transmitter and receiver coils. What is measured is the real electromagnetic power, representing the pure dispensation of energy that unambiguously demarcates the losses on either side. FC-TPM was demonstrated to be 0.1% accurate in hardware over an Rx coil misalignment of up to 10 cm using a 1-kW WPT system. Fair metering incentivizes businesses and individuals to make choices that conserve energy and advance technology by providing more information and by properly assigning the financial loss. This article is accompanied by a video highlighting the essential contributions of this article. [ABSTRACT FROM AUTHOR]

This paper investigates the impact of environmental conditions on the possible output power of photovoltaic (PV) installations on top of hybrid electric vehicles (HEVs) and battery-powered electric vehicles (BEVs). First, we discuss the characteristics and behavior of PV cells in order to provide an understanding of the energy source that we aim to integrate into vehicles. Second, we elaborate on how PV cells and panels can be simulated to estimate the potential extension of the electrical driving range (ERE) of BEVs and HEVs. In particular, we concentrate on the impact of the vehicle's curved roof surface on the possible output of the PV installation. In this research, we present considerations for vehicles in both parking and driving conditions. More precisely, we demonstrate how the frequently changing environmental conditions that occur while driving represent significant challenges to the control of the operating voltage of PV cells. As the area for deploying PV cells on top of an electric vehicle is limited, attention needs to be paid to how to optimize and maximize the degree of efficiency of PV-powered electric vehicles. [ABSTRACT FROM AUTHOR]

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The evolution of electric mobility is a promising strategy for decarbonizing the automotive sector. India is one of the countries that support having at least 30% of new vehicle sales be electric by 2030. To achieve the EV ecosystem to a considerable level, many efforts are required in EV charging infrastructure. Battery swapping is treated as a promising solution to accelerate the mass adoption of EVs in India. It is swapping model as an alternative to a lack of charging stations and to reduce range anxiety. This review paper discuss the role of batter swapping, its importance, pros & cons in 4-wheeler passenger car segments. It highlights the policy guidelines in India related to battery swapping, comparison of swapping vs. charging & ideal places for battery swapping station and role of EV battery pack. The review summary recommends the need to standardize the battery pack to enhance swapping among a single OEM across various name plates and among all OEMs with a collaborative effort. [ABSTRACT FROM AUTHOR]

The charging and levitation of particles using UV irradiation in an upward electric field were investigated. Glass beads with a mass median diameter of 61 μm were used for the experiments. The particle layers formed on a glass plate were irradiated by UV light with wavelengths ranging from 240 to 400 nm. The particles in the top layer were positively charged by photoemission and levitated by the electrostatic forces. The fluxes and motions of the levitated particles were analyzed by digital processing of the images obtained with a high-speed camera. The charge of each levitated particle was determined by fitting the results calculated using the equation of motion to the experimentally obtained particle motion. The charge of the particles beginning to be levitated was determined by the force balance and thus was not affected by the UV irradiance. The positive charge of the levitated particles could be increased by continuous photoemission from the particles and decreased by the capture of photoelectrons emitted by other particles. Approximately 40% of the levitated particles descended because of the negative charge clouds formed by the photoemission from the particle layers and the levitated particles. Furthermore, in a second set of experiments, an upward electric field was applied after UV irradiation. In these experiments, the particles in the top layer were levitated after applying the electric field. These particles could be gain more excess charges than the particles for which the levitation was governed by the force balance. [ABSTRACT FROM AUTHOR]

Foreign objects near wireless power transfer (WPT) systems are fire hazards that must be detected. In this article, a new accurate method is presented for foreign object detection based on an electromagnetic model for WPT. Foreign objects are detected by quantifying the deviation from a normal model. This deviation is caused by the foreign object's additional electromagnetic coupling. Advantages of this new method include invariance to receiver coil misalignment, and power level, allowing low-power detection prior to startup. Electromagnetic model-based foreign object detection was demonstrated in hardware to detect a 2 cm diameter U.S. nickel coin, a small disposable lighter, and a saline proxy for a living animal in a kilowatt-level wireless power transfer system, using a prestartup power of only 7 W. Furthermore, foreign objects can be detected regardless of an Rx coil misalignment of up to 10 cm. This article is accompanied by an instructional video. [ABSTRACT FROM AUTHOR]

The present work deals with thermal energy storage behavior of the nano-enhanced phase change materials (NEPCMs) for building space cooling application. The NEPCMs have been prepared using Deionized (DI) water as the base phase change material (PCM) and multi-walled carbon nanotubes (MWCNTs) as nanomaterial with mass concentration of 0.25%, 0.5%, and 0.75%. For better stability of additive materials in the base PCM, sodium dodecyl-benzene sulfonate (SDBS) has been chosen as an additive element. The sub-cooling of the DI water has been completely eliminated for a mass concentration of 0.75% of MWCNT. The differential scanning calorimetry(DSC) analysis has been conducted to measure the phase transition properties of NEPCMs. The enhancements of 12.8% and 14.13% in latent heat values for charging and discharging processes, respectively, were observed for maximum mass concentration. It has also been observed that the onset temperature for charging is reduced from − 12.8 to − 9.7 °C for NEPCM with maximum concentration. The maximum thermal conductivity (k) augmentation of 23% (solid phase) and 11.2% (liquid phase) has been achieved by the NEPCM having a mass concentration of 0.75% MWCNT at − 10 °C and 15 °C, respectively. According to the study results the reductions in total charging times are 28% and 19% with the NEPCM holding a mass concentration of 0.75% MWCNT for − 8 °C and − 6 °C heat transfer fluid (HTF) temperatures, respectively. The environmental pollution remediation can be achieved by the reduction in energy input to the chiller by minimizing the total time taken for the charging the PCM. [ABSTRACT FROM AUTHOR]

We are concerned with whether a vertically integrated broadband and content provider can unreasonably advantage itself over competing content providers, either by selling quality-of-service (QoS) to content providers at unreasonably high prices, or by refusing to provide access to QoS to competing content. We address this question by modeling the competition between one such vertically integrated provider and one over-the-top (OTT) content provider. We analytically determine when the broadband provider will sell QoS and when the OTT content provider or users will purchase QoS. We characterize the optimal QoS and video service prices. The ISP's market share increases with the difference in the value of the two video services and decreases with the difference in the corresponding costs. Numerical results illustrate the effect of QoS price on content price, and the variation of market share and profit with QoS price. The ISP may sell QoS to users at a lower price than when QoS is sold to the OTT provider.

With increasing concerns about urban pollution, electric vehicles (EVs) have offered an alternative mode of transportation that reduces urban pollution levels. Previous studies have sought to identify the various factors influencing EV charging patterns to deploy an appropriate charging infrastructure. However, limited attention has been paid to the investigation of different charging patterns identified in different regions at different phases of the EV program. This study aims to fill this research gap in the literature by developing binary logistic models that account for the factors influencing charging demands in different regions of Korea, i.e., Jeju-do and Gangneung-si. To this end, we collected historical data on EV charging transactions in these study regions and analyzed them to evaluate the difference in charging demands. The developed models suggest that the charging demand varies with charger characteristics and charging time. Moreover, different charging patterns in different regions can be explained by the different travel behaviors of those who use EVs for different trip purposes. These findings provide an important implication suggesting that policymakers should consider a stepwise strategy to construct charging infrastructure at the appropriate scale and configuration, depending on the phase of the EV program.

During the COVID-19—related lockdowns (2020–2022), mobility patterns and charging needs were substantially affected. Policies such as work from home, lockdowns, and curfews reduced traffic and commuting significantly. This global pandemic may have also substantially changed mobility patterns on the long term and therefore the need for electric vehicle charging infrastructure. This paper analyzes changes in electric charging in the Netherlands for different user groups during different phases of the COVID-19 lockdown to assess the effects on EV charging needs. Charging needs dropped significantly during this period, which also changed the distribution of the load on the electricity grid throughout the day. Curfews affected the start times of charging sessions during peak hours of grid consumption. Infrastructure dedicated to commuters was used less intensively, and the charging needs of professional taxi drivers were drastically reduced during lockdown periods. These trends were partially observed during a post–lockdown measuring period of roughly 8 months, indicating a longer shift in mobility and charging patterns.

Benefits from EV (Electric vehicles) and e-mobility include the reduction of local emissions of pollutants from particulate matter (PM0.5, PM5, and PM10) and nitrogen oxides (NOx and NO2). Cities and urban agglomerations benefit the most from potential emission reductions from EVs due to the large number of cars utilized in most urban traffic systems. This abstract presents results from a corporate research and funding project in Baden-Wuerttemberg, Germany (LINOx BW) which facilitates the installation of 2358 charging points within 178 different sub-projects in 23 different cities, spanning a period of four years. Utilizing several different survey waves, data about outgoing currents from these publicly funded charging points are gathered. Converting this data utilizing car classifications and emission classes (HBEFA), the reduction of local nitrogen oxides is derived.

The poor thermal performance of shell and tube latent heat storage (LHS) units using phase change materials restricts large-scale renewable energy utilisation. To address this issue, an innovative hierarchical fin is designed here to improve the charging performance of horizontal LHS units. The charging characteristics of innovative LHS units are explored and compared with available LHS units by a numerical model using the enthalpy-porosity scheme. Moreover, the response surface method (RSM) is applied to optimise the hierarchical fin by maximising its charging rate. The results indicate that hierarchical fins significantly improve the charging rate and temperature uniformity of horizontal LHS units. Except for the early heat conduction stage, melting convection develops as the dominant mode in the middle stage but decays in the later stage. Compared to tree-shaped fins, the hierarchical fin dramatically enhances heat conduction performance in the late melting stage, leading to a maximum reduction of 41.1% in the whole melting time of horizontal LHS units. To maximise the charging performance, the RSM results suggest the thickness gradient of the primary bifurcation, thickness fractal dimension, and length ratio of hierarchical fins should be 3.98, 1.34, and 1.11, respectively, providing constructive guidance for engineering applications of horizontal LHS units. [ABSTRACT FROM AUTHOR]

The effectiveness of inductive power transfer (IPT) presents a serious challenge for improving the global recharge system performance. An electric vehicle (EVs) needs to be charged rapidly and have maximum power when it is charged with wireless technology. Based on various research, the performance of this recharge system is attached to several points and the frequency resonance is one of those parameters that can influence. In this paper, we try to explore the relationship between the obtained power and the signal input frequency for charging a lithium battery, solve the class imbalance problem and understand the maximum allowed frequency. To obtain the results, a mathematical model was first created to demonstrate the relationship, then the dynamic model was validated and tested using the Matlab Simulink platform. The performance of the worldwide wireless recharging system in terms of frequency variation is depicted in a summary graph. [ABSTRACT FROM AUTHOR]

Due to increasing sales figures, the energy consumption of battery-electric vehicles is moving further into focus. In addition to efficient driving, it is also important that the energy losses during AC charging are as low as possible for a sustainable operation. In many situations it is not possible or necessary to charge the vehicle with the maximum charging power e.g., in apartment buildings. The influence of the charging mode (number of phases used, in-cable-control-box or used wallbox, charging current) on the charging efficiency is often unknown. In this work, the energy consumption of two electric vehicles in theWorldwide Harmonized Light-Duty Vehicles Test Cycle is presented. In-house developed measurement technology and vehicle CAN data are used. A detailed breakdown of charging losses, drivetrain efficiency, and overall energy consumption for one of the vehicles is provided. Finally, the results are discussed with reference to avoidable CO2 emissions. The charging losses of the tested vehicles range from 12.79 to 20.42%. Maximum charging power with three phases and 16 A charging current delivers the best efficiencies. Single-phase charging was considered down to 10 A, where the losses are greatest. The drivetrain efficiency while driving is 63.88% on average for the WLTC, 77.12% in the "extra high" section and 23.12% in the "low" section. The resulting energy consumption for both vehicles is higher than the OEM data given (21.6 to 44.9%). Possible origins for the surplus on energy consumption are detailed. Over 100,000 km, unfavorable charging results in additional CO2 emissions of 1.24 t. The emissions for an assumed annual mileage of 20,000 km are three times larger than for a class A+ refrigerator. A classification of charging modes and chargers thus appears to make sense. In the following work, efficiency improvements in the charger as well as DC charging will be proposed. [ABSTRACT FROM AUTHOR]

In the present contribution, the authors investigate the peculiarity of Phase Changing Material for accumulating heat in the region equivalent to the hilly area by creating its atmosphere, having 20°C DBT and 18°C WBT. A water cooler is used in 5*7 feet bathroom to conceive the above-intimated temperature, measured by a sling psychrometer. In particular, in this study, trials are carried out in the LHTES tank where water is charged from ambient temperature to 55°C with the aid of an Immersion water heater rod of 1000W,230V thereby liquifying PCM and then discharging to ambient temperature. Two Orientations namely, Circular and Cross are appropriated into the study, where Circular Orientation poses better results articulating the charging in an hour and discharging in 25 long hours, whereas Crossed Orientation represents charging in an hour and discharging in 23 hours. The volume of PCM and the net heat transfer surface have been kept constant in both cases, to compare them in the same operative conditions. The reason for the detour is manifested. [ABSTRACT FROM AUTHOR]

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In this study, electret media were loaded with neutralized and charged potassium chloride (KCl) to examine the effect of charged solid particles on loading behaviour. The media were then loaded with diethylhexyl sebacate (DEHS), dipropylene glycol (DPG) and glycerol to obtain a correlation between the efficiency degradation and liquid aerosol. The results indicated that the efficiency of electret media decreased from 72% to 46% under the neutralized KCl loading whilst the efficiency decreased from 96% to 82% under the positively charged KCl loading. Particle charging increased the initial efficiency and also effectively minimized the efficiency degradation. Given the increase in efficiency via chargers, the deposition morphology of the solid particles on the fibres was changed to mitigate the efficiency degradation. With respect to electret media loaded with DEHS, DPG and glycerol, the decrease in efficiency was associated with the solubility difference between the fibres and oil aerosols. Given sufficient affinity between the oil particles and fibres, oil molecules permeated the chain segments of the fibres and produced swelling that damaged the charge traps and decreased efficiency. The results of this study can guide practical electret filter operations and provide a better indoor environment. [ABSTRACT FROM AUTHOR]