WP2.2 Potential analysis for Electric Vehicle Grid Integration

31. October 2011

The report from WP 2.2 is about the potential for electric vehicle grid integration

Electric vehicles (EVs) have been considered as distributed energy resources (DER) to handle the fluctuation from renewable energy resources (RES), especially the wind power. The intelligent management of EV charging and discharging can achieve the goal of providing up and down regulating power from EVs to support the reliable and secure operation of future power systems with high penetration of RES. In the mean time, the EV charging management has to respect the driving needs of EV

The potential analysis for EV grid integration has been carried out to investigate the EV charging and discharging characteristics, the driving needs, spot price based EV charging management, and the available regulating power and economic return from providing regulating power.

An EV model has been developed based on the charging and discharging characteristics of Lithum‐Ion batteries. The driving needs and EV availability for charging have been reflected in the developed EV model as well and has been modeled as the charging and discharging constraints.

The Danish transport survey data (TU data) have been used to obtain the driving pattern in Denmark. The obtained driving pattern consists of time periods when cars are driving, time periods when cars are parked, and driving distance of each trip for cars of different user groups and different days within one week.

The spot prices have been used to determine the day‐ahead EV charging schedules. The spot price based EV charging can utilize the wind power as much as possible and minimize the charging cost.

Based on the spot price based EV charging schedule, the available up and down regulating power from EVs at different EV penetration levels have been obtained. The maximum EV penetration in the potential study is 70%. The up and down regulating power prices from the Nordic power market of 2010 has been analyzed to find out when it is profitable for EVs to provide the regulating power. The economical return from regulating power market has been obtained using the calculated available up and down regulating power and the regulating power prices.

The conclusion has been drawn based on the potential analysis that the available regulating power capacity is very promising. At the current regulating power prices, the economic return is not very high. It could be changed with more RES penetration.

In the potential analysis of EV grid integration, the grid constraints were not included. In the future work, the grid constraints have to be considered to get more accurate results.


Arne Hejde Nielsen