A new joint study by NAPA and ClassNK on real-life fleet shows that voyage optimization enables ships to reduce their emissions by 7.3% and maintain their CII ratings for an additional two to three years, giving shipowners precious decision-making time on decarbonization measures.
The joint study conducted with Marubeni Corporation with the aim to measure the impact of voyage optimization on the greenhouse gas emissions and Carbon Intensity Indicator (CII) ratings of a real-life fleet. In particular, the research also found that voyage optimization can improve a vessel’s CII by an average of 5-6%, enabling ships to maintain their ratings for an additional two to three years.
The joint research was carried out using NAPA’s ship performance model and voyage simulation tools. It used data on all voyages, weather and ocean conditions in 2021 for a group of bulk carriers owned and operated by Marubeni. The potential reductions in fuel consumption and CO2 emissions were measured by “retro-optimizing” each voyage to incorporate weather routing, using the data on weather and sea conditions that was available at the time and maintaining the same departure and arrival times.
ClassNK provided advice on the simulations, verified the calculated values and confirmed the results, while Marubeni provided the vessels for the demonstration tests, as well as its experience and expertise on operational aspects.
The joint study highlights the importance of optimizing voyages to improve a vessel’s rating under the International Maritime Organization’s CII regulation, which rates the carbon intensity of each vessel on a scale from A to E.
Our analysis shows that substantial emissions reductions can be achieved with tools that are available today. There is no reason to wait given the scale of the climate crisis. The study confirms that voyage optimization will be a powerful tool for the industry, not only to ensure compliance with CII requirements, but also to support shipping’s decarbonization journey.
Naoki Mizutani, Managing Director at NAPA Japan, said.
Takayuki Hase, General Manager of Ship Department at Marubeni, said: “As we navigate a new regulatory environment, data-driven insights are key to accurately assess our starting point, and fully understand the practical impacts. Based on cooperation and collaboration with industrial leading companies, we aim to contribute greener, more sustainable shipping though all practical methods.”
CII implementation poses challenges to shipping companies not just to ensure compliance but to plan and manage GHG emissions from their fleet, which directly impacts their competitiveness. Visualizing ships’ emissions should be a key initial step to envisage the way for optimized GHG management systems.
…Yoshimichi Sasaki, General Manager of Digital Transformation Center at ClassNK, said
