Bi-directional charging of electric vehicles for sustainable energy management with distributed solar generation

Electrifying road transport is essential for net-zero transitions, yet large-scale residential EV charging can intensify peaks in residential low-voltage distribution networks and increase technical losses. Prior studies show that bidirectional charging (V2G) can reduce peak demand and that distributed solar generation can offset local electricity use, but these resources are often analysed separately and rarely within an integrated framework that jointly quantifies peak impacts and converter-side and network-side efficiency penalties. This study develops a peak-minimisation optimisation model that coordinates EV charging and discharging while coupling V2G with distributed solar generation, including rooftop PV and vehicle-integrated PV. The model incorporates plug-in availability, daily mobility energy requirements, state-of-charge bounds, charging/discharging power limits, UK smart-meter household demand profiles, travel-behaviour-informed EV energy needs, home-availability patterns, and the IEEE European low-voltage test feeder. Four scenarios are compared: unidirectional charging, V2G, V2G with a grid-renewable setting, and V2G with distributed solar. Results show that V2G alone reduces peak demand by 5.72% at 50% EV penetration, whereas coupling V2G with distributed solar achieves a larger reduction of 14.62% and lowers feeder I2R losses, despite higher conversion losses from increased energy shifting. A Monte Carlo-based uncertainty analysis further confirms that these findings remain valid under combined weather variability and stochastic EV user behaviour. Under uncertainty, the PV-aware V2G scenario achieves the lowest mean peak demand, 21.73 kW, and the largest average peak reduction, 11.58%. These findings support PV-aware coordinated charging as a practical option for peak management, feeder-loss reduction and resilient residential low-voltage energy management.