Solar powered with BESS, grid connected system for EVCS FOR INDUSTRIAL APPLICATIONS

Abstract

This study examines technical and economic feasibility in the integration of grid-connected solar photovoltaic (PV) and battery energy storage (BES) in electric vehicle charging stations (EVCS) for industrial use. A 200 kWp crystalline silicon PV module combined with a 234-kWh lithium-ion battery system was simulated to provide four Level 2 charging stations (22 kW per station) for 4-16 electric vehicles per day in Manchester, UK. The system was modeled using MATLAB/Simulink with real solar irradiance data from PVGIS, targeting 85% renewable energy coverage of the 460-kWh daily charging demand. The technical analysis employed a centralized DC bus architecture with bidirectional converters for efficient energy management between PV generation, battery storage, EV loads, and grid connection. Monte Carlo simulation generated realistic EV charging patterns across three daily periods (8-11 AM, 12-4 PM, 5-8 PM) to assess system performance under variable demand conditions. Simulation results depicted successful system functionality with the PV array delivering maximum power output of 200 kW at maximum irradiance conditions (1000 W/m²). The incremental conductance MPPT algorithm presented stable convergence with duty cycles varying from 0.3 to 0.9. The BESS effectively compensated supply-demand variations with the battery SOC stabilizing at 90% while providing rapid charge/discharge responses to EV demand variations. The system could prioritize the utilization of the renewable energy with the battery as the initial buffer and minimal grid dependence, thus satisfying the intended objective of enabling EVCS from renewable energy with storage assistance. Economic analysis revealed high financial viability with a Net Present Value of £215,816, Internal Rate of Return of 12.3%, and payback period of 8.4 years over the 20-year project life. Levelized Cost of Electricity was determined to be at £0.10/kWh, which was competitive with grid electricity tariffs. Revenue streams were through EV charging fees (49.6%), peak demand savings (49.3%), and energy export (1.1%), totaling around £50,000 annually. The study demonstrates that grid-connected solar PV-BESS systems can provide technically feasible and economically efficient industrial EV charging infrastructure solutions, fostering decarbonization goals while reducing operational costs and grid dependence.