Electric Vehicles as Participants in the Flexibility System

Abstract Integrating electric vehicles (EVs) into the transportation system represents a crucial step towards achieving sustainable mobility and reducing greenhouse gas emissions. Technological advancements continuously enhance the performance and availability of EVs, making them significant players in the flexibility of energy grid systems. Electric vehicles not only provide an environmentally sustainable alternative to conventional vehicles but also act as mobile battery systems. These systems can be optimized for energy consumption management, balancing supply and demand in the electrical power system. Given the increasing share of renewable sources, the flexibility of EVs becomes essential. The analysis of home EV charger integration was conducted using the DIgSILENT PowerFactory software tool, utilizing quasi dynamic simulation. The simulations were performed on a rural network near Mostar on the weekday with the highest consumption, July 18, 2023. The simulation results indicated that the increase in the share of chargers significantly impacts the electrical grid. In the case of connecting 5% of chargers from the total number of consumers on the transformer station, an increase in network losses was recorded, but the transformer load remained below 100%. When the share increased to 15% of the total consumers, losses also increased, leading to transformer overload. However, by implementing load management strategies, where 50% of the 15% of consumers at overloaded transformer stations engage in demand response, system losses are mitigated, and transformer loading conditions are effectively optimized. This paper demonstrates that smart charging, along with strategies for optimizing charging times, can significantly reduce peak loads on transformers, improve the overall efficiency of the electrical power system, and simultaneously provide financial savings for end users.