The large spread of electric vehicles towards a mass market is essential to reduce pollutant and greenhouse gas emissions in the transport sector. However, the production of vehicle batteries is very energy consuming. So that the advantage of electro mobility in terms of CO2 emissions only become noticeable through a long service life of the batteries and correspondingly higher cumulative driven kilometers by the vehicle.
Due to the aging of the lithium-ion batteries in use, the range and the performance of e-vehicles decrease over their service life. However, a necessary replacement of the battery in the vehicle does not have to mean the end of the operation of battery. It can be further used in another application and still provide sufficient capacity with less power. As a result of a longer battery life the CO2 balance improves.
In order to open up the mass market for electric vehicles, it is crucial not only to offer charging opportunities in the garages of single-family houses, but also to include the masses in apartment houses. The project addresses this segment and demonstrates the solutions developed in a newly built district with single-family and apartment houses in Weinsberg. In addition to the primary task of intelligent recharging of electric vehicles, the charging infrastructure in the underground car parks should also offer flexibility grade to the energy management of entire building, like optimization of self-consumption rate for integrated PV plant.
Furthermore, for the demonstration site a car-sharing fleet with electric vehicles is planned either in the underground car parks or in the associated outdoor parking slots. The field tests are intended to determine to what extent operator and business models can be carried out with local building associated car sharing fleets. Since these vehicles are not privately owned, the batteries can be used as for the local load management, as for energy recovery into the building’s power grid more easily.
Central for the implementation and widespread use of the developed system solutions is the analysis of safety and reliability, as well as the certification of charging stations with aged vehicle batteries as buffer storage in underground garages. In this connection it is important to take into account as well as aging with its impact on the key safety factors, reliability and performance, as to determine the remaining service life to make the solutions technically and economically meaningful.