Study Reveals Potential Emissions Savings From Optimized Port Arrivals

A new study conducted by UCL Energy Institute and UMAS, analyzing global ship movements from 2018 to 2022, has revealed that optimizing port arrivals to consider congestion and waiting times could cut voyage emissions by up to 25% for certain vessel types.

Key Findings

1. Emission Savings by Vessel Type:
   • Chemical tankers: ~25% savings potential.
   • Gas carriers and oil tankers: ~16% savings potential.
   • Container ships and dry bulkers: ~10% savings potential.
2. Operational Inefficiencies:
   • Ships spend 4–6% of their operational time (15-22 days annually) waiting at anchor before berthing.
   • Smaller vessels tend to face longer waiting times, though this varies by type.
3. Trends in Waiting Times:
   • Chemical tankers, gas tankers, and bulk carriers saw an increase in waiting times, rising to 5.5-6% of their operational time by 2022.
   • Oil tankers and container ships’ waiting times remained constant (~4.5–5.5%).
4. Root Causes:
   • Common practices like “sail-fast-then-wait” and “first-come, first-served” scheduling.
   • Systemic challenges, including port congestion, inflexible charterparties, and limited stakeholder coordination.

Recommendations and Policy Implications

1. Holistic Application of CII Regulation:
   The Carbon Intensity Indicator (CII) should encompass all parts of the voyage, including idle time at ports, to incentivize stakeholders to collaborate on reducing GHG intensity across the value chain.
2. Operational Efficiency Improvements:
   • Targeting idle periods can generate immediate emissions reductions, a critical goal before 2030.
   • Addressing inefficiencies like port congestion can benefit low-income states struggling with decarbonization.
3. Global GHG Targets:
   • Dr. Tristan Smith emphasized that achieving the IMO’s revised GHG targets (20%-30% reductions by 2030) requires unlocking all efficiency opportunities.
4. Broader Systemic Efforts:
   Addressing inefficiencies at the ship-port interface supports both operational improvements and a just and equitable transition for all member states, particularly those with limited resources.

Expert Insights

• Dr. Tristan Smith, UCL: Urged for comprehensive measures to tackle market barriers and inefficiencies in port operations.
• Dr. Haydn Francis, UMAS: Highlighted the pressing need to address waiting times as part of the broader operational efficiency challenge.

For a detailed breakdown of findings and recommendations, read the full report: Port Congestion Report.

This study underscores the importance of integrated efforts between shipowners, port authorities, and stakeholders to achieve significant emissions reductions and improve overall maritime efficiency.