Determination of Optimal Locations of Electric Vehicle Charging Stations in Central Kampala

Abstract

Uganda is in its preliminary stages of adopting electric vehicles (EVs) with an aim to ensure that 25% of its vehicle fleet consists of purely electric vehicles. To achieve this goal, it is essential to increase the number of publicly accessible Electric Vehicle Charging Stations. This, in turn, will contribute to the development of sustainable transport. The focus of this research is to identify feasible locations for charging stations and to evaluate their potential impact on the electricity grid in Central Kampala Division. To achieve this, a combination of ArcGIS and DigSILENT is utilized. ArcGIS is employed for location suitability analysis, while DigSILENT is used to assess the effects on the grid. The study investigates three types of charging station locations: enroute charging, destination charging, and those outlined in a reference paper for comparison. The methodology consists of a GIS-based suitability analysis to pinpoint feasible locations for charging stations taking into account factors such as accessibility, proximity to major roads, and demand density. Subsequent to this, DigSILENT simulations are employed to evaluate the consequences of these charging stations at the EV penetration levels of 10%, 20%, and 30% on crucial grid parameters, including feeder loading, transformer loading, feeder voltage drop, and line losses. The simulation results demonstrate that as the penetration levels rise, there is an increase in feeder maximum loading, maximum voltage drop, feeder losses, and transformer loading. However, the loading of the various components does not exceed the acceptable limits of 80%, and the voltage deviation does not exceed ±10% either. In terms of their effect on the electricity grid, destination charging stations show the least impact when compared to enroute charging points and reference locations. Consequently, the study suggests that the identified locations should be upgraded into robust charging centres that can accommodate increased demand. Furthermore, the implementation of smart charging systems is recommended to effectively manage grid impact and reduce the possibility of grid overloads, thereby enhancing overall system reliability.