Making City - D3.18 Electric vehicles and charging stations roll-out strategy and analysis in Groningen

Electric vehicle charging at public charging stations is expected to account for a significant portion of PED grid loads in the coming years (Hoekstra & Refa, 2017). It is therefore important to understand the potential impacts of EV charging on the grid in order to develop a functional PED. Here, grid impact is defined as the amount of time and extent to which EV charging causes the electricity distribution grid to be overloaded. In this task, the design, monitoring and controlling strategies for the roll-out of public EV charging stations in the PEDs of Euroborg and Paddepoel will be Groningen will be outlined. In addition, this task will analyse the impact of public charging stations on the electricity grid in the long term, with different scenarios indicating the potential impacts of different charge control strategies. In the first version of this report, a total of 19 charging stations in the PED of Euroborg were monitored from mid-November, 2019, to the beginning of October, 2020. It must be noted that not all charging stations were active throughout the entire measurement period. During this period, a total of 1797 charge cycles were performed, delivering a total of 39.768 kWh of electricity. The average charge cycle length was 11,8 hours and the average charge cycle power was estimated at 2,87 kW. During the whole period, loads from at least one charging station were observed 68% of the time, while no charging occurred 32% of the time. Some of these values may be misleading because it is unclear if a charging station is actively providing power at the same rate throughout a charge cycle. Based on measurements and projections, grid impact is expected to increase at a lower rate as the number of charging stations increases. This results from the fact that as the number of charging stations and charging cycles increases, charging cycles become more spread over time, so that their relative grid impact is expected to decrease (absolute grid impact will, of course, continue to increase). The implications of this finding are twofold: First, if grid infrastructure is installed with sufficient capacity to meet the requirements of the projected number of charging stations, it is unlikely that this infrastructure will become overloaded as a result of EV charging in future. Second, since charging cycles are expected to overlap more frequently, it is expected that charge control strategies (i.e., interventions) will increase in effectiveness as the number of charging stations increases. In the final version of the report, charging stations in the PED of Paddepoel will be included, as well as additional scenarios which will analyse the potential effectiveness of different charge control strategies at reducing grid impact.

In this task, the design, monitoring and controlling strategies for the roll-out of public EV charging stations in the PEDs of Euroborg and Paddepoel will be Groningen will be outlined. In addition, this task will analyse the impact of public charging stations on the electricity grid in the long term, with different scenarios indicating the potential impacts of different charge control strategies.
In the first version of this report, a total of 19 charging stations in the PED of Euroborg were monitored from mid-November, 2019, to the beginning of October, 2020. It must be noted that not all charging stations were active throughout the entire measurement period. During this period, a total of 1797 charge cycles were performed, delivering a total of 39.768 kWh of electricity. The average charge cycle length was 11,8 hours and the average charge cycle power was estimated at 2,87 kW. During the whole period, loads from at least one charging station were observed 68% of the time, while no charging occurred 32% of the time. Some of these values may be misleading because it is unclear if a charging station is actively providing power at the same rate throughout a charge cycle.

Based on measurements and projections, grid impact is expected to increase at a lower rate as the number of charging stations increases. This results from the fact that as the number of charging stations and charging cycles increases, charging cycles become more spread over time, so that their relative grid impact is expected to decrease (absolute grid impact will, of course, continue to increase).
The implications of this finding are twofold: First, if grid infrastructure is installed with sufficient capacity to meet the requirements of the projected number of charging stations, it is unlikely that this infrastructure will become overloaded as a result of EV charging in future. Second, since charging cycles are expected to overlap more frequently, it is expected that charge control strategies (i.e., interventions) will increase in effectiveness as the number of charging stations increases.