Electric Vehicle Charging Loads in Residential Areas of Apartment Houses

Electric vehicle (EV) charging is expected to constitute a substantial part of the power demand in residential areas in the future. Its effects on the principles of distribution network planning and load profiles need to be studied. In this paper, we evaluate the feasibility of replacing the conventional cars with EVs in Finnish district heated apartment house areas. Stochastic simulation is used to combine a probabilistic charging model and electricity consumption data. We estimate the effects of uncontrolled, curtailed and price-optimized residential EV charging with different charging powers defined in the standards. The simulation results show that with 11.1 kW and 22.2 kW uncontrolled charging, the example apartment house connections would be overloaded. It is also found that the price-optimized charging should include a coordinated control logic that supports the local grid. With 1.84 kW charging, the power demand stays within the acceptable limits, but the coincidence factor increases from 0.2 to 0.63-0.93.