The growing adoption of electric vehicles (EVs) has made campus microgrid planning and operations more complex, underscoring the need for advanced microgrid design that balances cost and emissions reduction. In this study, a multi-objective optimization framework is developed on the XENDEE platform to determine optimal configurations for a campus microgrid integrating distributed energy resources (DERs) and EV charging infrastructure. Compared with a conventional grid-dependent campus, the DER-based microgrid demonstrates clear techno-economic and environmental advantages. The optimized plan reduces the generation-based levelized cost of energy (LCOE) from 0.2291 USD/kWh to 0.0430 USD/kWh. In comparison, the load-served LCOE decreases from 0.2685 USD/kWh to 0.0769 USD/kWh, reflecting notable improvements in generation efficiency and end-use energy delivery costs. In addition, annual electricity purchase expenditures decline from 4.611 million USD to 3.280 million USD, and the net present cost (NPC) is reduced to 3.050 million USD, yielding overall savings of 1.331 million USD annually. The optimized microgrid configuration has a payback period of 8 years, at which the internal rate of return (IRR) of 10% is achieved, satisfying the economic objective. Annual CO2 emissions are reduced from 2895 tons in the traditional grid-connected campus energy system to −71 tons under a net operational-emission accounting framework, in which avoided grid emissions from surplus renewable exports are credited. This corresponds to a net accounting-based emission reduction of 102.4%, indicating net operational carbon-negative performance and progress toward sustainable objectives.