Transportation and power system interdependency for urban fast charging and battery swapping stations in Croatia

An increasing penetration of electric vehicles in recent years has been driven by government and municipal subsidies, tax exemptions, parking access priority, as well as by the citizens' increased environmental awareness. Electric vehicles indisputably bring benefits to their drivers and society in general, indirectly through global warming and greenhouse gas emissions mitigation and directly through financial savings and cleaner microclimate. However, integration of electric vehicle charging spots at home or work, especially fast charging stations and battery swapping stations, without prior analysis can have a negative effect on power system. In order to predict and eliminate power grid issues before they occur, a detailed analyses should be made through a common understanding of both transportation and recharging needs of electric vehicles' users and of the power grid constraints. Power and transportation system interdependency becomes of high value for correct placement and sizing of charging stations and for overall increase of social welfare. This paper analyzes electric vehicles charging needs at the basic level, through both the power system and the transportation system. An urban transmission and power grid in the vicinity of the Croatian capital Zagreb is used as a study case. Driving and electricity consumption curves are compared, locations for charging infrastructure are selected (fast charging spots and battery swapping station) and power grid's available capacity is defined.