Optimal sizing of country-scale renewable energy systems towards green transportation sector in developing countries

Abstract

In the context of refining countries’ transition plans toward 100% shares of renewable systems in the electric power grids by 2050, this study aims to investigate, for the first time, the potential of covering the increasing energy demand for electric vehicles (EVs) using the previously planned hybrid renewable energy system (RES) for Jordan, which comprised wind, solar photovoltaic (PV), and battery energy storage systems (ESS). The optimal RES sizing is revisited to examine the influence of EV penetration percentages and charging rates (normal, medium, and fast) and optimize the charging periods to reduce system capacity. The results showed that for typical nighttime charging and relatively smaller EV penetrations, the RES system capacity remains the same, but the size of ESS must be increased by up to 16.67% for 25% EV penetration. As EV penetration increases, the required ESS capacity drops slightly, but the RES capacity increases by up to 24.53% for 100% EV penetration. Optimal charging periods were found to be during morning hours (6:00 to 9:00 a.m.). Adopting these early charging hours and compared to 0% EV, the required ESS capacity remained nearly the same, except for smaller EV penetration percentages. However, for 100% EV penetration, the increase in required capacity ranged from 24.5% for fast charging to 50.01% for normal charging. For lower penetration percentages, the three modes of charging resulted in comparable capacities of ESS and RES. As the penetration percentage increased to 100%, the fast charging mode required considerably lower RES capacity (by 17.0%) and the same ESS capacity of the 0% EV penetration.