Port call optimization is key to reducing emissions

Optimising port calls through SMART port technologies and ‘just in time’ (JIT) ship arrivals can significantly reduce greenhouse gas emissions at global container ports, according to Drewry’s latest research. Investing in ports with high waiting times will yield the most substantial industry benefits.

Shipping contributes nearly 3% of global greenhouse gas emissions, with ocean-going vessels being major emitters in port areas. Along with inland transport, these vessels generate significantly higher emissions than harbour support craft and cargo handling equipment.

Ports play a crucial role in the decarbonization of the shipping industry. Reducing emissions from ocean-going vessels, particularly during navigating, approaching, and waiting times, is essential. A major source of avoidable emissions is the time ships spend waiting at anchor before berthing.

Using its AIS model, Drewry analysed 193 of the world’s largest container ports, covering over 85% of global container trade. In 2023, pre-berth waiting times were 40% higher than in 2019, with significant regional variations due to differing traffic levels and port congestion.

Container shipping typically relies on pre-booked berthing windows. However, many vessels still operate on a ‘sail-fast-then-wait’ basis, leading to early arrivals and increased emissions. JIT arrival systems aim to align vessel speed with berth availability, reducing fuel consumption and emissions during both the voyage and port waiting periods.

Drewry’s analysis shows substantial variations in pre-berth waiting times among ports. For example, at Dar es Salaam, vessels waiting at anchor for over a week accounted for 70% of the total waiting time, totalling nearly 2,000 days in 2023. By reducing inbound voyage speed to 10 knots during congested periods, waiting time could have been cut by 31%, saving 23,000 CO2eq emissions. A 12-knot speed limit would save 16% of waiting time and 11,800 CO2eq emissions.

Coordination between ports can also reduce emissions, especially on shorter voyages. For instance, reducing the speed of vessels from Norfolk to Savannah to 10 knots during congested periods could cut pre-berth waiting by 24%, saving 7,250 CO2eq emissions. A 12-knot speed would save 6% of waiting time and 1,800 CO2eq emissions.

Implementing JIT arrival systems requires integrating port, terminal, and carrier management systems and interfacing with other service providers, posing significant organisational challenges, particularly in emerging markets. Despite these challenges, targeting investment in ports with high waiting times can deliver near-term emissions reductions and substantial industry benefits.