Vessel Prioritisation for Onshore Power Supply at the Port of Algeciras Using ILAPP

Onshore power supply (OPS) can reduce emissions from auxiliary engines during port stays, but limited electrical capacity and investment resources require vessel prioritisation. This study develops the Index for the Prioritisation of Onshore Power Implementation (ILAPP) and applies it to ferry and Ro-Ro traffic at the Port of Algeciras. The dataset comprised 3901 valid calls by 27 vessels during two periods in 2026; 25 vessels were retained for energy, emissions and EU Emissions Trading System (EU ETS) modelling. ILAPP integrated six criteria: call frequency, navigation fuel consumption, cumulative berth time, net CO2 reduction through OPS, gross tonnage and EU ETS exposure. Weights from a five-member expert panel were combined with objective CRITIC weights. A 60/40 expert–CRITIC configuration was selected after comparison with alternative hybrid schemes. Under the central scenario, OPS demand reached 18.32 GWh and yielded a net reduction of 11,370.11 tCO2, equivalent to 77.5% of conventional at-berth emissions. Total modelled CO2-related EU ETS allowance exposure for eligible vessels was approximately EUR 1.72 million, while displaced at-berth emissions represented EUR 0.74 million in potentially avoided allowance obligations. Kattegat ranked first, followed by Tanger Express, Villa de Agaete, Nápoles and Wasa Express. Temporal agreement was weak, although Kattegat remained first in both periods and in the aggregated sample. The results show that call frequency alone is insufficient and that correlated energy, environmental and regulatory criteria require balanced weighting. ILAPP provides a transparent vessel-level first-stage framework for identifying short-term and structural OPS priorities, while final investment decisions require additional technical, electrical and economic assessment.