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Modeling the temporal and economic feasibility of electric vehicles providing vehicle-to-grid services in the electricity market under different charging scenarios

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... EV owners use the valley tariff to fully charge at night, and when they arrive at their workplace, the idle EVs are managed by the V2G aggregators, thus making profits from the tariff difference. At the end of the workday, the V2G aggregators pay the fee according to the V2G technology's contracts and reserve a certain amount of power to enable the EV owners to return home safely [42]. The business scheme of peak-to-valley arbitrage using V2G technology is shown in Figure 5. Currently, numerous studies have investigated the economic feasibility of V2G technology participation in peak-to-valley arbitrage, with results being generally optimistic. ...
... Consequently, the application scenarios that require V2G technology capabilities primarily fall into three categories: home-based, workplace-based, and CSs-based. The V2G technology's application scenarios classified by location exhibit significant time-scale variations [42]. ...
... If CPs are not installed at home, the majority of EV owners will choose to charge their EVs at workplace [42]. Considering that the typical workday time spans around 8 hours, EVs at workplace have a significant amount of idle time. ...
Article
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Electric vehicles (EVs) play a crucial role in the global transition towards decarbonization and renewable energy resources (RERs). As EVs gain popularity, this has resulted in various challenges for the power grid, such as an intensified peak-to-valley load differential, causing transformer overloading. Vehicle-to-grid (V2G) technology has emerged as a promising solution due to its controllable charging and discharging capabilities. Mature business schemes can incentivize the development of V2G technology. However, the business schemes of V2G technology are still unclear. Therefore, this paper provides a comprehensive review of the business schemes associated with V2G technology, especially focusing on its feasibility and challenges with respect to the electricity market. In this paper, several business schemes with respect to the electricity market are explored by conducting extensive literature reviews, including peak-to-valley arbitrage, the spot market, demand–response (DR), frequency regulation, voltage regulation, spinning reserve, and black start. Next, application scenarios and real-world use cases of the V2G technology’s business schemes are investigated. Furthermore, the challenges faced by the V2G technology’s business schemes are assessed by considering the technical, economical, and social aspects. By identifying these challenges, it is important to highlight the existing shortcomings and areas of interest for V2G technology’s research and development. This review contributes to a deeper understanding of V2G technology and its implications for the energy sector.
... An optimization model was formed to maximize EV owners' profits; a quadratic function was used to describe the battery degradation costs in the V2G process. Three typical charging scenarios were evaluated by taking the New York electricity market as the case study [9]. A nonlinear function was formed to describe the EV battery degradation. ...
... To guarantee the daily travel demand for each EV, equation (8) is carried out to ensure that agents have sufficient energy to supply the driving demand of EVs in a disconnected state during time period t. At the same time, when EVs participate in frequency regulation service, the schedulable total energy during period t cannot be lower than the demand energy of EV in a disconnected state during that time period, as shown in the equation (9). ...
Article
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Electric vehicles (EVs) are likely to have a continuing presence in the vehicle market all over the world for the next few decades. The rapid development of large‐scale applications of EVs in China has provided a foundation for the implementation of vehicle‐to‐grid (V2G) technology. V2G can help EVs participate in grid regulation services. Based on the economic model of EV integration with the grid, the regulation ability and potential economic and environmental benefits brought by EV high penetration are analyzed using relevant data from Shanghai. Analysis results show that EV participation with V2G capability can not only reduce EV expenditures but also provide peak load‐shifting service. Further analyses show that with the increase of EV charging power and peak‐valley electricity price ratio and the decrease of battery loss cost, the economic benefits of V2G applications will increase. The large‐scale development of EVs also can effectively reduce CO2 emissions according to the model proposed.
... On the other hand, their willingness to participate in V2X has not been investigated in Sweden. Although several countries have started to investigate the barriers and willingness of EV owners to participate in the V2G program, e.g., [19][20][21][22][23][24][25][26], such studies are very limited in Sweden [31]. developed. ...
... On the other hand, their willingness to participate in V2X has not been investigated in Sweden. Although several countries have started to investigate the barriers and willingness of EV owners to participate in the V2G program, e.g., [19][20][21][22][23][24][25][26], such studies are very limited in Sweden [31]. In order to explore Swedish EV owners' willingness surrounding V2X implementation, namely, V2G and V2H, in this study, the authors relied primarily on data collection through an online questionnaire. ...
Article
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Vehicle-to-everything (V2X) refers to the technology that enables electric vehicles (EVs) to push their battery energy back to the grid. The system’s V2X integration includes key functions like V2G, V2H, V2B, etc. This paper explores the preferences of Swedish EV drivers in contributing to V2X programs through an online questionnaire. Respondents were asked to answer questions in three contexts: (1) claims related to their EV charging, (2) V2G application by EV, and (3) V2H application by EV. The respondents were questioned about the importance of control, pricing, energy sustainability and climate issues, impact on the battery, the acceptability of V2X, range anxiety, financial compensation, as well as how and where they prefer to charge the EV. The results of the survey indicate that Swedish EV drivers are more interested in the V2H application than in V2G. Additionally, they express more concern about range anxiety than battery degradation due to the V2X application.
... EV owners can also save money by using electricity when prices are low and generate extra income by reselling electricity to the grid when demand is Internal impedance (Ω) ΔE(T B ) Voltage compensation offset due to variation in temperature (K) dV OC /dT Change in voltage due to electrochemical reactions at its peak. Zheng et al. examined the economic viability and time availability of electric vehicles to determine their potential for providing vehicle-to-grid services [12]. Different charging scenarios including at fast charging stations, home, and work were examined. ...
... In the workplace context, Zheng et al. 20 found that workplace EV charging has significant potential to provide grid services, benefiting both the network operator and the EV owner. While there has been growing research interest in the benefits of providing grid services from EV batteries in recent years [21][22][23][24][25][26][27][28] , all the reviewed works in the literature have focused on the level (or existence) of benefits to network operators or electricity market agents [21][22][23][24] and EV owners [25][26][27][28] . ...
Article
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Expanding electric vehicle (EV) charging infrastructure is essential for transitioning to an electrified mobility system. With rising EV adoption rates, firms face increasing regulatory pressure to build up workplace charging facilities for their employees. However, the impact of EV charging loads on businesses’ specific electricity consumption profiles remains largely unknown. Our study addresses this challenge by presenting a mathematical optimisation model, available via an open-source web application, that empowers business executives to manage energy consumption effectively, enabling them to assess peak loads, charging costs and carbon emissions specific to their power profiles and employee needs. Using real-world data from a global car manufacturer in South East England, UK, we demonstrate that smart charging strategies can reduce peak loads by 28% and decrease charging costs and emissions by 9% compared to convenience charging. Our methodology is widely applicable across industries and geographies, offering data-driven insights for planning EV workplace charging infrastructure.
... Further studies have examined potential revenue streams for V2G services, such as frequency regulation 74 and renewable energy integration, 75 which can improve the economic income for both EVUs and grids. 76 The economic feasibility of V2G, however, faces several challenges. Battery degradation is a critical issue, as the frequent charge-discharge cycles associated with V2G can accelerate battery wear. ...
Article
Vehicle-to-Grid accelerates the transition to renewable, low-carbon power systems by integrating electric vehicles. This study analyzes the 2023 U.S. electric vehicle charging demand, variable renewable energy capacities, and charging infrastructure...
... Zheng et al. [121] investigated the viability of EVs for V2G applications based on two perspectives: time availability and financial viability. They assessed the suitability of three charging situations for V2G services: at home, at work, and at fast charging stations (FCSs). ...
Article
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Electric vehicles (EVs) must be used as the primary mode of transportation as part of the gradual transition to more environmentally friendly clean energy technology and cleaner power sources. Vehicle-to-grid (V2G) technology has the potential to improve electricity demand, control load variability, and improve the sustainability of smart grids. The operation and principles of V2G and its varieties, the present classifications and types of EVs sold on the market, applicable policies for V2G and business strategy, implementation challenges, and current problem-solving techniques have not been thoroughly examined. This paper exposes the research gap in the V2G area and more accurately portrays the present difficulties and future potential in V2G deployment globally. The investigation starts by discussing the advantages of the V2G system and the necessary regulations and commercial representations implemented in the last decade, followed by a description of the V2G technology, charging communication standards, issues related to V2G and EV batteries, and potential solutions. A few major issues were brought to light by this investigation, including the lack of a transparent business model for V2G, the absence of stakeholder involvement and government subsidies, the excessive strain that V2G places on EV batteries, the lack of adequate bidirectional charging and standards, the introduction of harmonic voltage and current into the grid, and the potential for unethical and unscheduled V2G practices. The results of recent studies and publications from international organizations were altered to offer potential answers to these research constraints and, in some cases, to highlight the need for further investigation. V2G holds enormous potential, but the plan first needs a lot of financing, teamwork, and technological development.
... In [10], the authors explored the latest distributed charging control schemes for EVs from the perspectives of charging network operators, EV users, and aggregators, which provided a reference for research on distributed optimization algorithms. In [11,12], the authors investigated the potential of EVs as distributed energy storage devices in participating in V2G services and assessed their influence on the power system, highlighting the practical challenges that V2G scheduling encounters when accounting for business models and market mechanisms. The former introduces temporal and economic indicators to evaluate the feasibility of EVs providing V2G services across various charging scenarios. ...
Article
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With the increasing penetration of electric vehicles (EVs), the spatial–temporal coupling between the transportation network (TN) and the power distribution network (PDN) has intensified greatly. Large-scale uncoordinated charging of EVs significantly impacts both the PDN and TN. In this paper, an optimal scheduling strategy for EV charging and discharging in a coupled power–transportation network (CPTN) with Vehicle-to-Grid (V2G) scheduling and dynamic pricing is proposed. The strategy considers the influence of dynamic transportation road network (DTRN) information on EV driving patterns, as well as the unique vehicle characteristics and mobile energy storage capabilities of EVs. Firstly, a DTRN model is established. Subsequently, the dynamic Dijkstra algorithm is utilized to accurately simulate the EV driving paths and predict the spatial–temporal distribution of the EV charging load. Secondly, optimal scheduling for EV charging and discharging within the CPTN is performed, guided by a V2G model coupled with a multi-time dynamic electricity price (MTDEP) strategy to optimize the grid load curve while accommodating the charging requirements of EVs. Finally, the effectiveness and superiority of the proposed optimization scheduling model are validated by the IEEE 33-node PDN test system.
... Incentive payments could draw more participants into V2G contracts, and trading carbon emissions in the system to balance the energy demand could reduce carbon emissions [41,42]. However, a study by Zheng et al. also showed that BEVs participating in V2G for revenue generation at current rates do not cover the cost of battery degradation [43]. Further cost reductions in the battery, decreases in battery degradation per cycle, and increased feed in tariffs or net metering credit are all needed to draw more BEV participants; this also opens up opportunities for using FC-EVs for V2G's implementation. ...
Article
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This paper presents an overview of the status and prospects of fuel cell electric vehicles (FC-EVs) for grid integration. In recent years, renewable energy has been explored on every front to extend the use of fossil fuels. Advanced technologies involving wind and solar energy, electric vehicles, and vehicle-to-everything (V2X) are becoming more popular for grid support. With recent developments in solid oxide fuel cell electric vehicles (SOFC-EVs), a more flexible fuel option than traditional proton-exchange membrane fuel cell electric vehicles (PEMFC-EVs), the potential for vehicle-to-grid (V2G)’s implementation is promising. Specifically, SOFC-EVs can utilize renewable biofuels or natural gas and, thus, they are not limited to pure hydrogen fuel only. This opens the opportunity for V2G’s implementation by using biofuels or readily piped natural gas at home or at charging stations. This review paper will discuss current V2G technologies and, importantly, compare battery electric vehicles (BEVs) to SOFC-EVs for V2G’s implementation and their impacts.
... Another study suggested that the widespread use of BEVs with higher battery capacities and the establishment of broader charging accessibility might diminish the peak demand from charging or shift the maximum demand time frame to one that is not aligned with peak household demand [19]. Furthermore, the stress of EDSs [20] could be reduced by implementing storage facilities at the CSs and promoting the potential provision of V2G services by electric vehicle owners [21]. Energies 2024, 17, 5314 3 of 29 ...
Article
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Battery electric vehicles represent a technological pathway for reducing carbon emissions in personal road transport. However, for the widespread adoption of this type of vehicle, the user experience should be similar to that of combustion engine vehicles. To achieve this objective, a robust and reliable public charging infrastructure is essential. In Spain, the electric recharging infrastructure is growing quickly in metropolitan areas but much more slowly on roads and highways. The upcoming charging stations must be located along high-volume traffic corridors and in proximity to the Trans-European Transport Network. The main contribution of this research is to offer a method for examining the essential electricity infrastructure investments required in scenarios involving substantial electric vehicle adoption. The methodology includes a sensitivity analysis of fleet composition and market share, recharging user behavior, charging station density, and vehicle efficiency improvements. To this end, the authors have developed a simplified probabilistic model, addressing the effect of the involved parameters through a comprehensive scenario analysis. The results show that the actual number of high-capacity charging plugs on Spanish roads is significantly lower than the European regulation requirements for the year 2030 considering an electric vehicle market share according to the Spanish Integrated National Energy and Climate Plan 2021–2030 objectives and it is far from the necessary infrastructure to cover the expected demand according to the traffic flow. Under these circumstances, the charging peak power demand reaches over 7.4% of the current Spanish total power demand for an electric vehicle fleet, which corresponds to only 12% of the total.
... Zheng et al. [11] found that workplace EV charging has significant potential to provide grid services, benefiting both the network operator and the EV owner. While there has been growing research interest in the benefits of providing grid services from EV batteries in recent years [12][13][14][15][16][17][18][19], all the reviewed works in the literature have focused on the level (or existence) of benefits to network operators or electricity market agents [12][13][14][15] and EV owners [16][17][18][19]. ...
Preprint
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Expanding electric vehicle (EV) charging infrastructure is essential for transitioning to an electrified mobility system. With rising EV adoption rates, firms face increasing regulatory pressure to build up workplace charging facilities for their employees. However, the impact of EV charging loads on businesses’ specific electricity consumption profiles remains largely unknown. Our study addresses this challenge by presenting a mathematical optimisation model, available via an open-source web application, that empowers business executives to manage energy consumption effectively, enabling them to assess peak loads, charging costs, and carbon emissions specific to their power profiles and employee needs. Using real-world data from a global car manufacturer in South East England, UK, we demonstrate that smart charging strategies can reduce peak loads by 28% and decrease charging costs and emissions by 9% compared to convenience charging. Our methodology is widely applicable across industries and geographies, offering data-driven insights for planning EV workplace charging infrastructure.
... Since 2016, the number of electric vehicles (EVs) in China has been climbing year by year and is expected to exceed 80 million in 2030 [2], but the charging demand of electric vehicle users presents randomness, and the large amount of random loads it generates will bring great challenges to the power grid [3], especially in terms of the balance of power supply and demand, grid stability, and economic feasibility [4]. But at the same time, EVs can also be used as distributed energy storage devices to provide vehicle-to-grid (V2G) services to alleviate grid overload and benefit the power system [5]. In addition, EVs can also be included in the optimal scheduling of the carbon market to improve the economic feasibility of China's low-carbon transition through the optimal scheduling of EV charging [6]. ...
Article
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The rapid development of electric vehicles (EVs) has brought great challenges to the power grid, so improving the EV load prediction accuracy is crucial to the safe operation of the power grid. Aiming at the problem of insufficient consideration of spatial dimension information in the current EV charging load forecasting research, this study proposes a forecasting method that considers spatio-temporal node importance information. The improved PageRank algorithm is used to carry out the importance degree calculation of the load nodes based on the historical load information and the geographic location information of the charging station nodes, and the spatio-temporal features are initially extracted. In addition, the attention mechanism and convolutional network techniques are also utilized to further mine the spatio-temporal feature information to improve the prediction accuracy. The results on a charging station load dataset within a city in the Hebei South Network show that the model in this study can effectively handle the task of forecasting large fluctuations and long time series of charging loads and improve the forecasting accuracy.
... Some of these studies have focused on simulating optimal charging strategies [24][25][26] and assessing the impact of different levels of EV penetration [27]. They have explored how EVs influence renewable energy integration [27][28][29][30], emissions [31,32], and cost analysis [33,34]. Additionally, there is ongoing research on V2G strategies and their effects on energy systems and energy storage requirements [35][36][37]. ...
Article
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As the global transition toward sustainable energy gains momentum, integrating electric vehicles (EVs), energy storage, and renewable energy sources has become a pivotal strategy. This paper analyses the interplay between EVs, energy storage, and renewable energy integration with Indonesia’s grid as a test case. A comprehensive energy system modeling approach using PLEXOS is presented, using historical data on electricity generation, hourly demand, and renewable energy, and multiple scenarios of charging patterns and EV adoption. Through a series of scenarios, we evaluate the impact of different charging strategies and EV penetration levels on generation capacity, battery storage requirements, total system cost, renewable energy penetration, and emissions reduction. The findings reveal that optimized charging patterns and higher EV adoption rates, compared to no EVs adoption, led to substantial improvements in renewable energy utilization (+4%), emissions reduction (−12.8%), and overall system cost (−9%). While EVs contribute to reduced emissions compared to conventional vehicles, non-optimized charging behavior may lead to higher total emissions when compared to scenarios without EVs. The research also found the potential of vehicle to grid (V2G) to reduce the need for battery storage compared to zero EV (−84%), to reduce emissions significantly (−23.7%), and boost penetration of renewable energy (+10%). This research offers valuable insights for policymakers, energy planners, and stakeholders seeking to leverage the synergies between EVs and renewable energy integration to pursue a sustainable energy future for Indonesia.
... 2. Literature review Sustainability must be ensured to conduct an effective market analysis for smart grid technology investments. The most important benefit of the sustainability perspective is that businesses do not focus only on short-term financial returns (Zheng et al., 2023a;Rahman, 2023). Instead, according to Tan et al. (2023), it is possible to say that sustainability takes into consideration the needs of future generations, since natural resources are not consumed unconsciously. ...
Article
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Purpose This paper aims to market analysis on the base many factors. Market analysis must be done correctly to increase the efficiency of smart grid technologies. On the other hand, it is not very possible for the company to make improvements for too many factors. The main reason for this is that businesses have constraints both financially and in terms of manpower. Therefore, a priority analysis is needed in which the most important factors affecting the effectiveness of the market analysis will be determined. Design/methodology/approach In this context, a new fuzzy decision-making model is generated. In this hybrid model, there are mainly two different parts. First, the indicators are weighted with quantum spherical fuzzy multi SWARA (M-SWARA) methodology. On the other side, smart grid technology investment projects are examined by quantum spherical fuzzy ELECTRE. Additionally, facial expressions of the experts are also considered in this process. Findings The main contribution of the study is that a new methodology with the name of M-SWARA is generated by making improvements to the classical SWARA. The findings indicate that data-driven decisions play the most critical role in the effectiveness of market environment analysis for smart technology investments. To achieve success in this process, large-scale data sets need to be collected and analyzed. In this context, if the technology is strong, this process can be sustained quickly and effectively. Originality/value It is also identified that personalized energy schedule with smart meters is the most essential smart grid technology investment alternative. Smart meters provide data on energy consumption in real time.
... Furthermore, the lack of concrete business models slows down V2G adoption [17]. V2G was investigated for the New York electricity market in [18] based on economic aspects and the availability of time for the charging. ...
Article
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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.
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Vehicle-to-Grid (V2G) technology enables electric vehicles (EVs (Unless otherwise specified, Electric Vehicles (EVs) in this study refer to the totality of BEVs, PHEVs, and other battery-equipped vehicles that have the potential to participate in V2G)) to interact with renewable energy sources, positioning it as a key driver of energy system decentralization. While V2G holds significant potential for enhancing grid stability and economic efficiency, its large-scale deployment requires a robust economic assessment. However, existing research predominantly focuses on technical feasibility, lacking comprehensive economic evaluations due to the complexity of V2G system architectures. To bridge this gap, we propose the BSTP (Business-Stakeholders-Technology-Policy) V2G economic evaluation framework and the VRR (Value Realization Rate) methodology, employing a Semi-Systematic Co-Design Approach. This framework systematically characterizes the evolution of V2G business models, the interactions among key stakeholders, the influence of technological and policy factors, and the criteria for economic feasibility assessment. Furthermore, we identify a “Big Models, No Trials” issue in V2G economic research, where large-scale theoretical models lack empirical validation. To address this challenge and ensure the practical applicability of our framework, we define six core challenges that must be resolved for a rigorous economic evaluation of V2G. Our findings provide a structured foundation for future research and policy development, offering insights that could accelerate the transition to decentralized energy systems.
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Vehicle-to-Grid (V2G) technology is a transformative solution aimed at enhancing the sustainability and resilience of electric grid infrastructure. This paper provides a review of V2G technology on its technical, economic, and environmental aspects. The paper explains the integration of renewable energy, V2G’s potential to reduce greenhouse gas (GHG) emissions, and its role in improving grid stability through ancillary services. The study discusses the limitations of technical requirements concerned with battery degradation, communication protocols, and cybersecurity associated with grid connectivity. The paper further highlights the economic opportunities of V2G covering the market trends, policies, and regulations that can support widespread adoption. Additionally, implemented V2G cases are analyzed to explore the potential emerging technologies that could address the barriers to V2G large-scale deployments. We also present the major pitfalls that can stand in the way of utilizing electric vehicles (EVs) as dynamic and distributed energy resources (DERs) to serve the future.
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div class="section abstract"> Nowadays, electrification is largely acknowledged as a crucial strategy to mitigate climate change, especially for the transportation sector through the transition from conventional vehicles to electric vehicles (EVs). As the demand for EVs continues to rise, the development of a robust and widespread charging infrastructure has become a top priority for governments and decision-makers. In this context, innovative approaches to energy management and sustainability, such as Vehicle-to-Grid (V2G), are gradually being employed, leading to new challenges, like grid service integration, charge scheduling and public acceptance. For instance, the planned use scenario, the user’s behavior, and the reachability of the geographical position influence the optimal energy management strategies both maintain user satisfaction and optimize grid impact. Firstly, this paper not only presents an extensive classification of charging infrastructure and possible planning activities related to different charging scenarios but also indicates the most feasible Point of Interest (POIs) for certain energy strategies and a user’s behavior associated with POIs. Secondly, the article proposes a systematic procedure to analyze the potential location using accessible data from OpenStreetMap (OSM), considering different POIs categories and the classifications proposed above. Therefore, this methodology can support future practitioners both in the definition of the suitability of a charging geographical position for specified energy management strategies (e.g., V2G) and the best path planning for a defined charging location. Lastly, the proposed model is applied to a real case study, functional to the XL-Connect Horizon Europe project. The results proposed utilized open-source geographical data and can be obtained for other worldwide case studies. </div
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Given the rapid growth of electric vehicles (EVs) ownership and the accelerated construction of novel energy systems, it is urgent to promote the integration of EVs and integrated energy systems (IESs). This study proposes a tri-level optimization model to optimize the operation and capacity of the IES with the orderly charging/discharging (OCD) of EVs considering individual EV behavior. In which, the trip schedule and state of charge (SOC) demand of EVs is predicted by a spatiotemporal-SOC characterization model. Moreover, through the charging and discharging quote based on the trend of time-of-use tariffs to guide the OCD of each EV, the decoupling of the OCD decision-making and IES scheduling is achieved based on an interaction level and a pre-calculation method. Finally, this study optimizes the operation and capacity of the IES with the minimum operating cost and total cost, respectively. Following a simulation case study, the results show that the IES with OCD of EVs can reduce the operating cost by 12.1 % at the expense of 0.9 % increase in equipment cost, which is significantly better than that with the electrical energy storage devices (EESs) which reduces the operating cost by 6.9 % at the expense of 7.9 % increase in equipment cost. Moreover, integrating the OCD of EVs with the EESs can reduce the operating cost by 17.9 % and the final total cost by 7.4 %. At the same time, EV owners in general not only achieve free charging but also receive an overall daily revenue of 613.3 CNY to supplement the additional battery degradation loss of EVs. This study also conducted uncertainty analyses on the number of EVs, battery capacity and charging/discharging power, and energy prices. Generally, this study investigates the economic and technical feasibility of integrating EVs with IES.
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The integration of electric vehicles (EVs) into the electricity grid through vehicle-to-grid (V2G) technology represents a promising opportunity to improve energy efficiency and stabilize grid operations in the context of building sustainable cities. This paper provides a systematic review of the literature to assess the status of the research and identify the road ahead. Using bibliometric analysis and systematic assessment, the critical factors that influence the charging behavior of electric vehicles, the adoption of V2G, and the effective use of EVs as dynamic energy resources are identified. The focus is particularly on the ecological transitions toward sustainability, travel characteristics, technical specifications, requirements, and barriers in real use, and the behavioral and psychological aspects of stakeholders. The results lay the foundation for accurate forecasts and the strategic implementation of V2G technology to support the needs of the electric grid. They emphasize the importance of considering the psychological and behavioral aspects of users in the design of V2G strategies and define the key factors to predict the demand for electric vehicle charging. Furthermore, they highlight the main barriers to V2G adoption, which are primarily related to concerns about battery degradation and economic issues. Privacy and security concerns, due to data sharing with electric vehicle aggregators, also limit the adoption of V2G. Addressing these challenges is essential for the successful integration of electric vehicles into the grid.
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The aim of this work was to create an original numerical model for conducting an economic analysis of Vehicleto-Grid (V2G) services. This model enables the computation of potential economic earnings for a certain user providing V2G services to the grid operator, considering Portugal's electricity market and the country's increasing adoption of Electric Vehicles (EVs). The model incorporates various parameters in its calculations, including battery degradation, distance traveled, charging frequency, number of V2G charge-discharge cycles, electricity purchase and sale prices or the cost of new batteries. These factors contribute to robust values that facilitate a detailed analysis closely aligned with the realities of different citizens, since no study found in the literature has addressed the economics of V2G technology in this sense. To test this model, we created four hypothetical EV users with distinct characteristics, aiming to understand the scenarios where providing this energy storage service is most beneficial from the EV user perspective. We considered and compared three scenarios for the selling price of electricity back to the grid (0,50 €/kWh, 0,30 €/kWh, and 0,20 €/kWh) and performed a sensitivity analysis. The goal is that by the time each user needs to replace their battery due to degradation, they will have generated sufficient income from the V2G service to not only cover the cost of a new battery (10,000 €) but also make a profit. This takes into account the future development of energy storage and the anticipated decline in prices. Results suggest that the V2G service can be highly beneficial when electricity sale prices are high (0,50 €/kWh) for users with very low car usage (profits of 624 € per month and 1547 € in total after the costs of a new battery), but the same doesn't happen when the prices for selling electricity to the grid drop to 0,30 or 0,20 €/kWh. This service can be advantageous too for users who use their cars intensively, even if the electricity selling price is low (0,20 €/kWh), as it allows for savings on the purchase of a new battery (savings between 300 € - 1100 € on the cost of a new battery).
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Chapter
For the past few years, urban areas have been grappling with increasing pollution and traffic congestion. The adoption of electric rickshaws presents a promising solution for sustainable and clean urban mobility. However, integrating these e-rickshaws into the electrical grid successfully necessitates careful planning and the installation of renewable energy alternatives. Various challenges are faced by the conventional grid systems in accommodating the charging needs of growing fleet of e-rickshaws; and this problem is faced by most of the states in India. Cases of power theft for charging e-rickshaws have become quite common. And thus, to overcome this problem, charging stations can be made separately for e-rickshaws by using renewable energy sources. This chapter deals with the setting up of a plant using renewable energy in a place called ‘Seoraberia,' Howrah, West Bengal, by using biogas and PV as the main source of renewable energy.
Preprint
Electric vehicle (EV) batteries are often underutilized. Vehicle-to-grid (V2G) services can tap into this unused potential, but increased battery usage may lead to more degradation and shorter battery life. This paper substantiates the advantages of providing load-shifting V2G services when the battery is aging, primarily due to calendar aging mechanisms (active degradation mechanisms while the battery is not used). After parameterizing a physics-based digital-twin for three different dominant degradation patterns within the same chemistry (NMC), we introduce a novel metric for evaluating the benefit and associated harm of V2G services: \textit{throughput gained versus days lost (TvD)} and show its strong relationship to the ratio of loss of lithium inventory (LLI) due to calendar aging to the total LLI (LLICal/LLI\text{LLI}_\text{Cal}/\text{LLI}). Our results that focus systematically on degradation mechanisms via lifetime simulation of digital-twins significantly expand prior work that was primarily concentrating on quantifying and reducing the degradation of specific cells by probing their usage and charging patterns. Examining various cell chemistries and conditions enables us to take a broader view and determine whether a particular battery pack is appropriate for load-shifting (V2G) services. Our research demonstrates that the decision "to V2G or not to V2G" can be made by merely estimating the portion of capacity deterioration caused by calendar aging. Specifically, TvD is primarily influenced by the chemistry of cells and the environmental temperature where the car is parked, while the usage intensity and charging patterns of EVs play a lesser role.
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Today in developed megacities, municipal waste incinerators are a practical solution although they require a relatively high initial investment. On the other hand, E-Transport is growing in metropolitans along with the Renewable Energy Sources (RES). This study proposes an Urban Micro Grid (UMG) consisting of a Waste-to-Energy Combined Heat and Power generation unit (WtE-CHP) and series of Plugin Electric Vehicles (PEV). The main purpose is to provide ancillary services through the incorporation of PEVs as fast-responsive storages. The parking lots may aggregate to form PEV clusters and make bilateral contracts with WtE-CHP to be able to participate in the regulating power markets. A Crow Search Algorithm (CSA) is developed for the UMG operation. In addition, a data analysis section is provided focusing on the behavior of urban drives to extract the realistic probabilities for PEVs available during the daytime. Moreover, the power market of Denmark east (DK2) is considered for the case study of Copenhagen. The results confirm that in case the UMG succeeds in selling the products in the regulating up market, the economic value per MW is remarkably enhanced and the total profit is escalated.
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Photovoltaics (PV) and electric vehicles (EVs) are two emerging technologies often considered as cornerstones in the energy and transportation systems of future sustainable cities. They both have to be integrated into the power systems and be operated together with already existing loads and generators and, often, into buildings, where they potentially impact the overall energy performance of the buildings. Thus, a high penetration of both PV and EVs poses new challenges. Understanding of the synergies between PV, EVs and existing electricity consumption is therefore required. Recent research has shown that smart charging of EVs could improve the synergy between PV, EVs and electricity consumption, leading to both technical and economic advantages. Considering the growing interest in this field, this review paper summarizes state-of-the-art studies of smart charging considering PV power production and electricity consumption. The main aspects of smart charging reviewed are objectives, configurations, algorithms and mathematical models. Various charging objectives, such as increasing PV utilization and reducing peak loads and charging cost, are reviewed in this paper. The different charging control configurations, i.e., centralized and distributed, along with various spatial configurations, e.g., houses and workplaces, are also discussed. After that, the commonly employed optimization techniques and rule-based algorithms for smart charging are reviewed. Further research should focus on finding optimal trade-offs between simplicity and performance of smart charging schemes in terms of control configuration, charging algorithms, as well as the inclusion of PV power and load forecast in order to make the schemes suitable for practical implementations.
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The increasing integration of electric vehicles (EVs) is adding higher future potentials for the smart grid because the residual energy stored in EV batteries can be discharged to support the grid when needed. However, the stochasticity of EV user behaviors pose challenges to the regulators of distribution systems. How the regulators decide upon a control strategy for the vehicle to grid and how EV users respond to the strategy will significantly influence the variation of load profiles in the planning horizon. In this paper, a comprehensive cost analysis is performed to obtain the optimal planning scheme, considering the variation in EV penetration, charging preference, and customer damage cost. The economics and stability of the planned distribution system are assessed with real-world travel records and cost statistics to quantitatively show the effectiveness of the optimization algorithm and the importance of user behavior concern.
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Coordinated charging can utilize the properties of electric vehicles (EVs) to obtain various benefits. However, there are two major challenges, viz. the uncertainty of EV charging behaviors and the overlong solving time for the optimal solutions in the charging scheduling problem of large-scale EVs. It is almost infeasible to precisely predict the charging information of EVs due to the uncertainty of their mobility as transportation tools. In order to tackle this issue, the real-time charging scheduling method is employed in this paper. Even so, the computational complexity is crucially important in the real-time scheduling methods since the charging strategies of large-scale EVs must be acquired in a short time. Hence, a high efficient methodology is proposed for EV real-time scheduling based on the definition of capacity margin index and charging priority index. Finally, the simulation results show that the proposed scheduling method has a significant superiority over the uncoordinated charging in the regard of relieving the demand stress on the power system. Moreover, the complexity analysis demonstrates that the proposed method has near-linear complexity so that it can acquire the optimal real-time charging scheme in a rather shorter time than other methods.
Article
The risk of accelerated electric vehicle battery degradation is commonly cited as a concern inhibiting the implementation of vehicle-to-grid (V2G) technology. However, little quantitative evidence exists in prior literature to refute or substantiate these concerns for different grid services that vehicles may offer. In this paper, a methodology is proposed to quantify electric vehicle (EV) battery degradation from driving only vs. driving and several vehicle-grid services, based on a semi-empirical lithium-ion battery capacity fade model. A detailed EV battery pack thermal model and EV powertrain model are utilized to capture the time-varying battery temperature and working parameters including current, internal resistance and state-of-charge (SOC), while an EV is driving and offering various grid services. We use the proposed method to simulate the battery degradation impacts from multiple vehicle-grid services including peak load shaving, frequency regulation and net load shaping. The degradation impact of these grid services is compared against baseline cases for driving and uncontrolled charging only, for several different cases of vehicle itineraries, driving distances, and climate conditions. Over the lifetime of a vehicle, our results show that battery wear is indeed increased when vehicles offer V2G grid services. However, the increased wear from V2G is inconsequential compared with naturally occurring battery wear (i.e. from driving and calendar ageing) when V2G services are offered only on days of the greatest grid need (20 days/year in our study). In the case of frequency regulation and peak load shaving V2G grid services offered 2 hours each day, battery wear remains minimal even if this grid service is offered every day over the vehicle lifetime. Our results suggest that an attractive tradeoff exists where vehicles can offer grid services on the highest value days for the grid with minimal impact on vehicle battery life.
Article
In expectation of extensive usage of electric vehicles (EVs) in the near future, vehicle-to-grid (V2G) system is envisioned to be a key component of the smart grid, and it has demonstrated great potential in providing valuable ancillary services such as load balancing, regulation, and reserves. The success of a V2G system largely depends on a credible incentive scheme to motivate a huge number of EVs to participate, but the side effect is that EVs in V2G may suffer from privacy risks concerning their whereabouts. So far little has been done to address the privacy threat, and existent work is inefficient in computation and communication and/or provides defective protection. In this paper, we propose a privacy-preserving solution for V2G communications known as PRAC (Privacy via Randomized Anonymous Credentials). As a full-fledged security protocol suite, PRAC features not only anonymity and untraceability for EVs in authentication as well as service rewarding, but also rewarding fairness and non-repudiation. Thorough analysis reveals that PRAC is secure and is also cost-effective. Compared with the V2G literature, this paper features a prototype implemented on commodity hardware and free software. Extensive experiments demonstrate that PRAC is likely to be a promising solution for any modern electric vehicle.
Article
The need to reduce greenhouse gas emissions and fossil fuel consumption has increased the popularity of plug-in electric vehicles. However, a large penetration of plug-in electric vehicles can pose challenges at the grid and local distribution levels. Various charging strategies have been proposed to address such challenges, often separately. In this paper, it is shown that, with uncoordinated charging, distribution transformers and the grid can operate under highly undesirable conditions. Next, several strategies that require modest communication efforts are proposed to mitigate the burden created by high concentrations of plug-in electric vehicles, at the grid and local levels. Existing transformer and battery electric vehicle characteristics are used along with the National Household Travel Survey to simulate various charging strategies. It is shown through the analysis of hot spot temperature and equivalent aging factor that the coordinated strategies proposed here reduce the chances of transformer failure with the addition of plug-in electric vehicle loads, even for an under-designed transformer while uncontrolled and uncoordinated plug-in electric vehicle charging results in increased risk of transformer failure.
Article
Smart charging systems for battery electric vehicles (BEVs) are one promising smart grid technology that has the potential to help balance energy supply and demand. In the present study, we aimed to investigate users' real-life experiences with a smart charging system and their evaluation of it. In a 5-month field trial, 10 BEV drivers compared conventional BEV charging with smart charging. Via smartphone application, users could modify settings which determined the charging process (e.g., departure times). Before and after experiencing the prototype system, users' motivation, attitudes, willingness to use smart charging and charging behavior were assessed via interviews and questionnaires. Furthermore, participants reported how they experienced and integrated the smart charging system. Results showed that users were motivated and positive about the system at both points of data collection. On average, users agreed that the system is suitable for daily life, reliable and trustworthy. They were willing to use smart charging before and after testing it, but some participants stated that reliability of the system should be improved. In sum, results indicate that a smart charging system like the one implemented in this study is assimilable in everyday life and provide valuable indications for further development of smart charging systems.
Day ahead optimization of an electric vehicle fleet providing ancillary services in the Los Angeles Air Force Base vehicle-to-grid demonstration
  • DeForeast
An extended simplex method
  • Wolfe