{"title":"A fluid vacation model for renewable-powered electric vehicle charging systems: Performance evaluation and cost-optimal battery sizing","authors":"A.P. Nikhil, T.G. Deepak","doi":"10.1016/j.apenergy.2026.127537","DOIUrl":null,"url":null,"abstract":"<div><div>The widespread adoption of electric vehicles (EVs) and the global transition toward renewable energy have created an urgent need for sustainable, reliable, and cost-efficient EV charging infrastructures. Renewable-powered EV charging stations (EVCSs), although environmentally attractive, are highly vulnerable to the intermittency of renewable generation and the limited capacity of local battery energy storage systems. These challenges can result in charging interruptions, queue congestion, and degraded quality of service, particularly in off-grid or weak-grid environments.</div><div>This paper develops a unified analytical framework to evaluate the performance and economic trade-offs of renewable-powered EVCSs under energy uncertainty. The proposed model is based on a <em>Markov Fluid Vacation Queue (MFVQ)</em>, which jointly captures stochastic renewable energy harvesting, finite-capacity battery storage dynamics, and random EV arrivals. The battery energy buffer is modeled as a continuous fluid queue driven by renewable inflow and charging demand, while EVs form a finite-capacity queue with stochastic arrivals and charging times. Energy shortages are explicitly represented through service interruptions in off-grid systems and grid-assisted operation in hybrid on-grid configurations.</div><div>Using the proposed framework, we quantify how renewable variability and battery capacity affect EV waiting delays, service reliability, and energy availability. These results are then used to develop a <em>cost-optimal battery sizing</em> methodology that balances battery investment cost against performance degradation due to energy scarcity and EV queue congestion. Numerical case studies based on realistic system parameters demonstrate that the proposed MFVQ-based approach provides practical design insights and enables informed decision-making for the planning and operation of off-grid and hybrid renewable-powered EV charging stations.</div></div>","PeriodicalId":246,"journal":{"name":"Applied Energy","volume":"410 ","pages":"Article 127537"},"PeriodicalIF":12.2000,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Applied Energy","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0306261926001893","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2026/2/20 0:00:00","PubModel":"Epub","JCR":"Q1","JCRName":"ENERGY & FUELS","Score":null,"Total":0}
引用次数: 0
Abstract
The widespread adoption of electric vehicles (EVs) and the global transition toward renewable energy have created an urgent need for sustainable, reliable, and cost-efficient EV charging infrastructures. Renewable-powered EV charging stations (EVCSs), although environmentally attractive, are highly vulnerable to the intermittency of renewable generation and the limited capacity of local battery energy storage systems. These challenges can result in charging interruptions, queue congestion, and degraded quality of service, particularly in off-grid or weak-grid environments.
This paper develops a unified analytical framework to evaluate the performance and economic trade-offs of renewable-powered EVCSs under energy uncertainty. The proposed model is based on a Markov Fluid Vacation Queue (MFVQ), which jointly captures stochastic renewable energy harvesting, finite-capacity battery storage dynamics, and random EV arrivals. The battery energy buffer is modeled as a continuous fluid queue driven by renewable inflow and charging demand, while EVs form a finite-capacity queue with stochastic arrivals and charging times. Energy shortages are explicitly represented through service interruptions in off-grid systems and grid-assisted operation in hybrid on-grid configurations.
Using the proposed framework, we quantify how renewable variability and battery capacity affect EV waiting delays, service reliability, and energy availability. These results are then used to develop a cost-optimal battery sizing methodology that balances battery investment cost against performance degradation due to energy scarcity and EV queue congestion. Numerical case studies based on realistic system parameters demonstrate that the proposed MFVQ-based approach provides practical design insights and enables informed decision-making for the planning and operation of off-grid and hybrid renewable-powered EV charging stations.
期刊介绍:
Applied Energy serves as a platform for sharing innovations, research, development, and demonstrations in energy conversion, conservation, and sustainable energy systems. The journal covers topics such as optimal energy resource use, environmental pollutant mitigation, and energy process analysis. It welcomes original papers, review articles, technical notes, and letters to the editor. Authors are encouraged to submit manuscripts that bridge the gap between research, development, and implementation. The journal addresses a wide spectrum of topics, including fossil and renewable energy technologies, energy economics, and environmental impacts. Applied Energy also explores modeling and forecasting, conservation strategies, and the social and economic implications of energy policies, including climate change mitigation. It is complemented by the open-access journal Advances in Applied Energy.