Challenges and barriers of integrating e-cars into a grid with high amount of renewable generation

In this contribution international experiences concerning the integration of electrified cars (e-cars) into the grid in particular when there is a high penetration of renewable energies are presented. Future shortage of fossil fuels and concerns about security of supply derived the idea of electrified mobility which requires a new approach to design a complex system for future transportation. This system will be based on existing infrastructures (electricity system, road infrastructure, etc.) but it can also partially be considered as a "green field" approach. In the paper new strategies and global trends in the development of an e-mobility system will be presented, including strategies to combine the power system with the information and communication systems as well as a logistics. Practical experiences and data based on few projects e.g. Harz.EE-Mobility in Germany. European research as well as industry projects with these aims will be introduced and results will be presented. The main focus is twofold: integrating the upcoming mobile loads into the grid and likely storage possibilities that can operate bidirectional within the power grid. Simulations show that single-phase charging (3.7 kW) in the low and medium voltage grid does not lead to grid situations that require any significant adjustments in the power network regarding the loading of the assets. However, uncoordinated single-phase charging could create significant voltage deviations due to unbalanced loading of the three-phase low voltage grid. The different phases influence each other in unbalanced situations, through the common neutral conductor. These effects can already occur at low market penetration levels, due to the presence of local penetration levels being significantly higher than the average market level