Optimal integration of Renewables and Second-Life batteries to improve the environmental sustainability of Electric Vehicle Fleets

Electrification of the transport sector and massive installation of renewables are seen as two cornerstones for achieving a carbon neutral energy system. Nevertheless, uncontrolled electric vehicle charge combined with fluctuating energy production could induce power quality issues and system inefficiencies, causing an opposite outcome. Thus, in order to make sure that the energy system could benefit from electric mobility and renewable energy sources installation, proper design and control strategy of the charging stations is crucial. The aim of this study is to implement an optimal design methodology for an Electric Vehicle charging station located at a workplace. PV peak power, Electric Energy Storage capacity with retired Electric Vehicle batteries and number of charging columns to install are optimally defined targeting the carbon neutrality of the charging station operation. Two different charging strategy are implemented and compared to quantify the influence of the control approach on the final optimal charging station configuration. Moreover, energy demand and production uncertainties are taken into account in the production of the input data. The obtained results suggest that an optimal control strategy allows to have always a greater emission reduction and to downsize the PV and Electric Energy Storage capacity needed to achieve the carbon neutrality of the EV charging process.