Techno-economic optimization of a hybrid renewable microgrid for electric vehicle charging: A comparative study in Egypt and Türkiye

• A multi-objective framework optimizes a hybrid PV-Wind-Hydrogen-Battery microgrid. • System design targets near-zero Loss of Power Supply Probability for EV charging. • Hybrid storage (Battery/H2) is proven essential for high reliability and resilience. • Comparative analysis reveals distinct optimal designs for Egypt and Turkey contexts. • Turkey achieves a lower LCOE ($0.0173/kWh) due to balanced wind and solar resources. The rapid electrification of transport demands EV charging stations supplied by clean, reliable power. This paper presents an optimal sizing framework for an off-grid hybrid renewable microgrid combining photovoltaic arrays, wind turbines, battery energy storage (BESS), and hydrogen energy storage (HESS) to achieve zero loss of power supply probability (LPSP = 0). A four-objective Indicator-Based Evolutionary Algorithm (IBEA) is used to minimize levelized cost of energy (LCOE), curtailment ratio (CR), and LPSP while maximizing renewable fraction (RF). The method is tested in two locations: Attaka, Suez Governorate (Egypt) and Yalova Province (Türkiye), quantifying how climate and finance affect sizing and cost. Türkiye attains a lower LCOE of $0.0173/kWh with RF = 53.03% and CR = 17.11%, versus Egypt's $0.0261/kWh, RF = 50.35%, and CR = 27.67%—a 51.3% cost advantage driven by balanced solar-wind resources and higher EV demand. Egypt requires substantially larger BESS capacity (227 units vs. 34) to manage solar variability due to its solar-dominant resource profile. Sensitivity analysis reveals that discount and inflation rates dominate LCOE variation (±18–23% impact), while wind speed and load demand drive operational performance (±15–18% impact). Critical break-even thresholds are 47.5–50% (Türkiye) and 27.75–30% (Egypt), indicating Egypt's greater financial fragility. All designs satisfy the strict zero-LPSP constraint (≤0.001%), confirming the effectiveness of coordinated battery–hydrogen storage for reliable, cost-effective EV charging across diverse climatic and economic contexts.