The increasing prevalence of electric vehicle (EV) fleets (EVF) is largely attributed to their considerable environmental advantages. To further promote sustainability, microgrids present a practical solution for university campuses by combining renewable energy (RE) sources (RES) with traditional power systems. This research focuses on planning and optimising a grid-integrated EVF microgrid utilising the hybrid optimisation of multiple energy resources (HOMER) optimisation. A total of ten distinct scenarios were evaluated to identify the most efficient and cost-effective configuration for the university campus. Among these, Scenario 6, which incorporates photovoltaic (PV) panels, an energy storage system (ESS), and a diesel generator (DG), emerged as the most favourable option for the considered geographical location. This scenario exhibited outstanding economic and environmental performance, achieving a net present cost (NPC) of 55.35 million INR and a levelised cost of electricity (LCOE) of 0.04 INR/kWh. The study investigates the selection of suitable RES based on the geographical location of the university campus to optimise microgrid planning. Furthermore, the environmental benefits of the proposed microgrid configuration were quantified, showing a remarkable reduction in emissions to 3.407 tonnes compared to a conventional grid-connected campus emission. To ensure the robustness of the system, a sensitivity analysis was conducted by varying key input parameters, including EV load, campus load, solar radiation, temperature, nominal discount rate and inflation rate. The analysis confirmed the resilience of Scenario 6 under different conditions, reinforcing its viability as a sustainable and cost-effective energy solution.