EV Charging Station with Solar Monitoring and Grid Integration

Abstract

The rapidgrowthofelectricvehicleshascreated an urgent demand for sustainable and efficient charging infrastructure to reduce reliance on conventional power grids. Most current charging stations depend solely on grid electricity,whichcanbe expensive and unreliable in power-deficient or remote areas. This project presents a prototype for a smart electric vehicle charging station designed to provide a cost-effective and eco-friendly charging alternative. The primary objective is to develop a system that utilizes solar energy as the primary powersource while integrating the utility grid as a backup toensure uninterruptedoperation.Themethodologyinvolvesa hierarchical energy management strategywheresolarpower is prioritized, followed by battery storage, and finally the grid. The system is built around an ESP32 microcontroller, which monitors solar voltage, battery status, and grid availabilityinreal-time.Anautomaticswitchingmechanism using a relay module enables the seamless transferbetween energy sources based on programmed logic. Testing results from the hardware prototype validate the system\'sabilityto maintain a stable charging voltage and switch to the grid when solar supply is insufficient, such as during nighttimeor cloudy weather. Thefinaloutcomeisareliable,low-cost, and scalable charging solution that contributes to the advancement of green energy adoption in thetransportation sector.

Introduction

The study focuses on developing a smart EV charging system to support the global shift toward sustainable electric mobility. While electric vehicles help reduce emissions and fossil fuel dependency, their widespread adoption depends on efficient and reliable charging infrastructure. Current systems rely heavily on the power grid, lack intelligent management, and face issues like high costs, environmental impact, and limited scalability.

To address these challenges, this research proposes a smart EV charging station that integrates solar energy, battery backup, and grid power using an ESP32 microcontroller. The system uses a “Solar → Battery → Grid” priority logic, ensuring maximum use of renewable energy while maintaining uninterrupted charging. It also includes real-time monitoring through IoT, relay-based automatic switching, and a cost-effective, scalable design.

The literature review highlights previous work on solar-based charging systems, hybrid models, and efficiency improvements, but identifies gaps such as complexity, lack of automation, and limited real-time monitoring. The proposed system aims to balance efficiency, affordability, and simplicity.

The system architecture consists of input (solar and grid), control (ESP32 and sensors), and output (relay switching and charging point) subsystems. The methodology includes simulation, hardware integration, and algorithm development for automated decision-making.

Results from simulations and hardware testing show that the system effectively prioritizes solar energy, switches accurately between sources, maintains stable voltage and current levels, and achieves high efficiency with less than 5% error. Overall, the study demonstrates a reliable, eco-friendly, and intelligent EV charging solution suitable for future sustainable infrastructure.

Conclusion

A. Summary of Work The research presented in this paper successfully designed and implemented a prototype for a smart electric vehicle (EV) charging station that integrates solar energy with the utility grid. By utilizing an ESP32 microcontroller as the central processing unit, the system manages energy flow based on a hierarchical priority logic that favors renewable energy utilization. The hardware implementation,supported by MATLAB/Simulink modeling,demonstratesafunctional creating an eco-friendly charging alternative that maintains reliability through intelligent grid integration. B. Performance Achievement The systemdemonstratedrobustperformanceacrossvarious environmental conditions, accurately identifying voltage thresholdstomanagesourceswitching.Experimentaltesting validated that the system prioritizes solar energy when voltage levels are sufficient, automatically transitioning to battery or grid backup only when renewable generation is inadequate.Simulationresultsconfirmedthatthe MPPT-controlled regulation stabilizes the charging voltage near therated12Vlevel,ensuringsafeenergytransfertothe battery. Furthermore, the charging current was successfully maintained within safe limits, preventing thermal stress on the storage components. C. Technical Contribution The primary technical contribution of this work is the development of a low-cost, intelligent energy management framework that combines real-time IoT monitoring with automated switching. Unlike conventional grid-dependent systems, this prototype uses a \"Solar-First\" strategy implemented via firmware on the ESP32 to reduce grid dependency. The integration of a 16times2 LCDdisplayfor local parameter visualization enhances user transparencyand system monitoring. Additionally, the use of resistive voltage dividers and relay-based switching provides a practical blueprint for building resilient, small-scale EV infrastructure in power-deficient regions. D. LimitationsandFutureImprovements Despite the successful validation of the prototype, certain limitations remain. The current system is a small-scale prototype with limited power output, making it unsuitable for commercial or full-scale electric vehicles in its present form.Additionally,theprototypelacksadvancedhigh-frequency isolation and sophisticated IoT cloud dashboards for remote management. Future improvements will focus on scaling the system for higherpowerratingsto support actual EV loads. Potential enhancements include: Integrating IoT cloud platforms for remote monitoring and data logging via the ESP32’s built-in Wi-Implementing advanced Maximum Power Point Tracking (MPPT) algorithms to further optimize solar energy harvesting under varying conditions. Addingbi-directionalpowerflow capabilities to allow excess solar energy to be exported back to the grid. Incorporating a tilt-adjustablesolarpanelmechanismto maximizephotovoltaicefficiencythroughouttheday. Overall, this project marks a significant step toward achieving sustainable and intelligent charging solutions for the future of clean transportation.

References

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Copyright

Copyright © 2026 Mr. Ritesh C. Gabhane, Mr. Rakesh Kumar S. Yadav , Mr. Dhanesh K. Barve , Mr. Yash R. Dardemal , Ms. Sharvari M. Mundle , Mr. Shubham S. Nimbekar . This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.