Cold ironing impacts on greenhouse gas fuel intensity and IMO net-zero fund contributions

This study examines the techno-economic implications of cold ironing within the Greenhouse Gas Fuel Intensity (GFI)–based compliance methodology of the IMO Net-Zero Framework for an oceangoing bulk carrier. The vessel was assessed under base case and possible cold ironing deployment scenarios, covering port stay, anchorage, and bunkering operations, using one year of operational data. The analysis explicitly integrated cold ironing utilization into the ship-level GFI formulation, quantifying Tier 1 and Tier 2 compliance deficits, remedial unit requirements, and associated compliance costs for the 2028–2035 reporting periods. The results showed that the reference vessel remains within the Tier 2 compliance region under current operating conditions, implying annual contributions to the IMO Net-Zero Fund exceeding USD $1.2 million by 2028 and approaching USD $1.75 million by 2030 under the proposed remedial unit pricing structure. A full-scale cold ironing application can reduce the attained annual GFI by 1.7% and yield substantial economic benefits through reduced auxiliary fuel consumption and lower remedial unit payments, with cold ironing remaining economically viable for electricity prices below USD $0.30 per kWh. While cold ironing alone does not achieve direct GFI compliance, the study demonstrates its effectiveness as a cost-efficient, near-term mitigation option.