Application of Rechargeable Batteries of Electrical Vehicles as Time Dependent Storage Resource for the Public Electricity Grid

Abstract

This study investigates the potential to use the EES storages of a fleet of privately owned Electrical Vehicles (EV) as time dependent storage source connected to the electrical grid. The example of the national German electricity grid is examined. Calculations are done as time series on a complete yearly set of quarter-hour data for generation and consumption, as obtained from the national regulatory authority (“Bundesnetzagentur”). Future scenarios foresee targets that have been publicly stated by the German government, e.g. the projected discontinuation of electricity generation by nuclear power, the envisaged shares of renewables within the electricity mix per 2030 or 2050, and a projected evolution of the number of EV. Besides, the technical evolution like introduction of new types of EES like the Li-Air-storage promising higher storage capacity in the future is expected. The model assumes that private users of EV will provide the storage capacity within their EV to the public grid following a certain time pattern. A minimum reserve for the user is always granted and moreover it is assumed that the electrical system operator will make compensation payments to the user of the EV. In a scenario beyond 2030 where 6 Mio EV are projected, the number of EV is assumed to be 20 Mio EV in 2050. This results in a considerably large distributed storage to help dealing with a future more and more volatile electricity provision by more and more renewable energy sources, especially wind and PV. According to our preliminary results, an optimum for this model can be obtained at moderate power levels for charge and discharge, avoiding the necessity for a comparable high invest of “fast charging” stations.