Multi-objective hybrid renewable energy planning for port decarbonisation: marine-resource complementarity, storage choice and abatement economics

A small Mediterranean port can cut its electricity-related greenhouse-gas emissions by four fifths while paying less per kilowatt-hour than its retail tariff, provided its renewable supply is designed as an integrated portfolio. The study asks which local resources belong in that portfolio, which storage should support it and whether a carbon price changes the answer. A grid-connected photovoltaic, wind, wave and tidal system with battery or hydrogen storage is sized for a Trans-European Transport Network port from hourly series: 28 configurations by a seeded, replicated genetic algorithm, then the cost against lifecycle-emissions frontier by non-dominated sorting. The cost-optimal design (360 kW photovoltaic, 112 kW wind, 30 wave converter units, 1512 kWh of battery storage) supplies electricity at EUR 0.1996/kWh against a EUR 0.36/kWh tariff and cuts annual emissions from 678.7 to 124.7 t CO 2 -eq (81.6%). Twenty of the 22 co-located configurations abate carbon while reducing cost, at EUR -396 to -5 per tonne, so the investment needs no carbon price; deepening decarbonisation along the frontier costs 493 EUR/t, and within the eight-hour frontier no step between neighbouring designs exceeds the search’s single-run variability; only the move to sixteen hours of autonomy does. Wave energy earns its place by generating in all 8760 hours and supplying 40.7% of its energy at night; the local tidal current never reaches the 1.25 m/s cut-in. Batteries beat hydrogen and hybrid storage by at least 0.02 EUR/kWh and seven percentage points at both autonomy levels. The reduction depends on the adopted grid emission factor