The transportation sector of the world is in the transformation stage, shifting from conventional fossil fuel-powered vehicles to zero or ultra-low tailpipe emission vehicles. To support this ...transformation, a proper charging station (CS) infrastructure in combination with information technology, smart distributed energy generating units, and favorable government policies are required. The motive of this paper is to address the key aspects to be taken care of while planning for the charging station infrastructure for electric vehicles. The paper also provides major indagation and developments in planning and technological aspects that are going on for the enhancement of the design and efficient management of charging station infrastructure. The paper addresses the present scenario of India related to electric vehicle charging station developments. The paper specially provides a critical review on the research and developments in the charging station infrastructure, the problems associated with it, and the efforts that are going on for its standardization to help the researchers address the problems.
Electric vehicle (EV) is essential to reduce the emission caused by conventional vehicle. Placement of electric vehicle charging station (EVCS) is crucial to fulfilling the charging demand at ...different locations maintaining the minimum negative impact on the power system network. In this article, placement of EVCS has been planned in a radial distribution network superimposed with a road network. The weightage for different places have been considered as per charging demand which depends on the supermarket, road junctions, residences etc. The objectives are minimization of the energy loss, voltage deviation of the power system network and minimization of the land cost with maximum weightage to serve maximum EV with minimum establishment cost. The area has been divided into three zones to establish an EVCS at each zone to make it distributed. Uncertainties related to EV have been considered in this work using 2m Point Estimation method (2m PEM). The optimization problem has been solved using Differential Evolution (DE) and Harris Hawks Optimization (HHO) techniques.
In this article, a solar photovoltaic (PV) array, a battery energy storage (BES), a diesel generator (DG) set, and a grid-based electric vehicle (EV) charging station (CS) is utilized to provide the ...incessant charging in islanded, grid-connected, and DG set connected modes. The CS is primarily designed to use the solar PV array and a BES to charge the EV battery. However, in case of exhausted storage battery and unavailable solar PV array generation, the CS intelligently takes power from the grid or DG set. However, the power from DG set is drawn in a manner that it always operates at 80%-85% loading to achieve maximum fuel efficiency under all loading conditions. Moreover, in coordination with the storage battery, the CS regulates the generator voltage and frequency without a mechanical speed governor. It also ensures that the power drawn from the grid or the DG set is at unity power factor even at nonlinear loading. Moreover, the point of common coupling voltage is synchronized to the grid/generator voltage to obtain the ceaseless charging. The CS also performs the vehicle to grid active/reactive power transfer, vehicle to home, and vehicle-to-vehicle power transfer for increasing the operational efficiency of the CS. The operation of the CS is experimentally validated using the prototype developed in the laboratory.
•An evaluation framework for equipping electric vehicle charging stations with renewable energy is proposed.•The retrofitting potentials are 889.87 kWh/m2 for Hanyang, 826.41 kWh/m2 for Wuchang, and ...796.32 kWh/m2 for Hankou.•Electric vehicle charging stations near six different building types are analyzed.•The installation of renewable energy charging infrastructure near hotels yields the greatest benefits.•The results provide a reference for policymakers and charging facility operators.
In this study, an evaluation framework for retrofitting traditional electric vehicle charging stations (EVCSs) into photovoltaic-energy storage-integrated charging stations (PV-ES-I CSs) to improve green and low-carbon energy supply systems is proposed. Using existing EVCSs in the “10-minute living circle residential areas” of seven central urban districts in Wuhan city, we comprehensively consider factors such as the site distribution, sky view factor and service population to assess the economic and environmental benefits of PV-ES-I CS systems at different locations and scales. The research results show that the central urban districts have high retrofitting potential, with 44 stations north of the Yangtze River and 20 stations south of the Yangtze River being most suitable for retrofitting. The economic and environmental benefits vary significantly across building types; the retrofitting/construction of PV-ES-I CSs near hotels yields the greatest economic benefit and carbon dioxide emission reduction per unit investment.
•Demand-side energy management is studied for EVCS with multiple types of chargers.•An approximate dynamic programming based energy management system is proposed.•Optimal charging start time of each ...EV is determined by the proposed EMS.•Maximum charging autonomy can be guaranteed at the device level.•Operation costs can be reduced by over 50% in the numerical studies.
The high operation cost of the EV charging station (EVCS) is a severe challenge for the development of electric vehicles, which lead to the general shortage of the EVCS. In order to reduce the operation costs of the EVCS, an approximate dynamic programming (ADP) based energy management system (EMS) is proposed for the EVCS equipped with multiple types of chargers (EVCS-MTC). A fuzzy logic guiding system has been designed to allocate each vehicle an appropriate charging spot based on its charging urgency. Multiple EVs can acquire the charging service through a common charger in the EVCS-MTC. In the proposed EMS, the approximate dynamic programming (ADP) and the evolution algorithm (EA) are combined to determine the optimal charging start time for each EV. This characteristic provides the charging device with the maximum autonomy to select the preferred flexible charging pattern, which can prolong the battery lifetime and reduce the communication requirements of the control system. With taking the dynamic electricity price and uncertain future charging demand into account, the proposed EMS can achieve a total cost reduction of over 50% compared with the conventional charging scheme in the numerical studies.
China's government has built a certain scale of charging station network. To address the problems of low charging station network utilization, the existence of a large number of redundant charging ...stations, and the diffi-culty of charging, this paper proposes a data-driven charging station network optimization approach. Firstly, this paper simulates the charging behavior of EV (electric vehicle), establishes queuing systems for charging stations in different time stamps, and then estimates the arrival rates among charging stations. On this basis, the spatial characteristics of urban EV charging behavior are analyzed, which is used to explore the urban EV charging hotspots. Then, the interactions among competitive dependencies, geographic features and user charging preferences among charging stations are modeled, and a scoring function is proposed to assess the usage benefit of charging station in the network. Lastly, a charging station network optimization model which aims at maximizing the usage benefit of c
Due to the low pollution and sustainable properties, using electric buses for public transportation systems has attracted considerable attention, whereas how to recharge the electric buses with long ...continuous service hours remains an open problem. In this paper, we consider the problem of placing electric vehicle (EV) charging stations at selected bus stops, to minimize the total installation cost of charging stations. Specifically, we study two EV charging station placement cases, with and without considering the limited battery size, which are called ECSP_LB and ECSP problems, respectively. The solution of the ECSP problem achieves the lower bound compared with the solution of the ECSP_LB problem, and the larger the battery size of the EV, the lower the overall cost of the charging station installation. For both cases, we prove that the placement problems under consideration are NP-hard and formulate them into integer linear programming. Specifically, for the ECSP problem we design a linear programming relaxation algorithm to get a suboptimal solution and derive an approximation ratio of the algorithm. Moreover, we derive the condition of the battery size when the ECSP problem can be applied. For the ECSP_LB problem, we show that, for a single bus route, the problem can be optimally solved with a backtracking algorithm, whereas for multiple bus routes we propose two heuristic algorithms, namely, multiple backtracking and greedy algorithms. Finally, simulation results show the effectiveness of the proposed schemes.
The mass adoption of electric vehicles (EVs) continuously requires the expansion of charging resources in the urban area. Such a continuing and dynamic problem associated with multi-level of ...uncertainties can hardly be tackled by deterministic models. To overcome this challenge, this paper newly proposes a progressive planning scheme (PPS) for dynamic expansion of charging resources deployment. Specifically, a simulation environment is constructed by considering EV user behavior model and evaluation model. Based on this, a tailored deep reinforcement learning (DRL) model is proposed to direct the concerned expansion problem, of which the objective is to enhance social welfare while adhering to specific economic and technical constraints. The proposed model leverages an attention mechanism and an inflation coefficient to enable the agent to selectively focus on dominant features and effectively adapt to variable planning schemes. Moreover, the DRL model is incorporated with Monte Carlo Tree Search (MCTS) to obtain the exploration-exploitation trade-off, through which more valid and generalizable decisions can be generated. Comparative case studies are carried out to verify the efficiency and robustness of the proposed methods, which demonstrate averaging 4.79% and 11.38% improvement over the advanced reinforcement learning algorithm and the genetic algorithm in an approximating real-world environment, respectively.
Graphical Abstract Abstractable representation of the paper.
In this paper, a comprehensive review of the impacts and imminent design challenges concerning such EV charging stations that are based on ...solar photovoltaic infrastructures is presented, which is based on state-of-the-art frameworks for PV-powered charging stations and the latest case studies. The main factors that are targeted in this review are the management of an EV charging system that is a composite of PV and public grid, as well as a charging system business model that can affect consumer behavior by charging at different rates and the best design infrastructure for a PV electric vehicle charging services. The economic, environmental, and social impacts caused by the installation of PV-driven charging infrastructures are also compared. Moreover, the framework for recently emerging vehicle-to-grid and vehicle-to-home services, as well as the integration of these frameworks, is discussed. Finally, survey results for future EV demand and its public acceptance are presented. Appertaining to these issues, the case studies highlight that EV transportation between parking lots and charging stations is necessary to make the best use of the available charging stations. Statistically, in this study, it was inferred that there are no limitations on the amount of EV battery capacity that can be stored, and users of EVs can charge in both slow and fast modes. Furthermore, V2G systems are not suitable for widespread industrial use. Moreover, finding solutions and overcoming numerous obstacles remain unaddressed issues, and the size of the EV industry must reach a certain level to make profitable sales of V2B, V2H, V2G, and other V2X systems. The collected statistics indicate that although respondents generally have a favorable opinion of the mobility applications powered by photovoltaic cells, it seems unlikely that they will use them anytime soon.
The world population depends highly on fossil fuels, particularly for transportation and power generation. This dependency leads to oil price increases because of the depletion of fossil fuels. ...Burning of fossil fuels also increases greenhouse gas emissions that are greatly responsible for global warming. Thus, electric vehicles (EVs) are considered one of the premium solutions in the land transportation system because they can significantly reduce the dependency on crude oil and minimize transportation-related carbon dioxide emissions along with other pollutants. This study presents an extensive review of the three key areas of EV research, namely, EV charging technologies, the various impacts of EVs, and optimal EV charging station (CS) placement and sizing. Several technical publications related to EV charging technologies are highlighted, and the performance comparison of different EV technologies is discussed. A review of literature on these key areas reveals an increasing interest in these topics in the last decade, with the impacts of EV on the electric power system and the optimal placement and sizing of CS issues widely investigated. By providing an overview of these areas, this study demonstrates the current issues and challenges of widespread deployment of EVs in the market as well as the future research direction in this field. A total of 185 publications are arranged and appended for quick referencing.
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