Rotor sails and voyage optimization yield up to 28 pct CO2 cuts, study finds

The combination of NAPA Voyage Optimization with the Norsepower Rotor Sail™ can deliver emissions reductions of 28%, on average, on the Atlantic route between New York and Amsterdam, a study has found.

The findings are part of a simulation project carried out in cooperation with Norsepower, a Finland-based provider of auxiliary wind propulsion systems, maritime software expert NAPA, and Japanese shipbuilder Sumitomo Heavy Industries Marine & Engineering Co., Ltd. (SHI-ME).

Phase one of the joint simulation project looked at the fuel-saving and emissions-reduction potential of combining Norsepower Rotor Sail™ and NAPA Voyage Optimization onboard SHI-ME’s wind propulsion ship. 

Phase one of the simulation project was took place from December 2002 to March 2023. The findings show that of the 28% average CO₂ emissions savings, the contribution of NAPA Voyage Optimization can be estimated at 12%. 

The joint simulation project leveraged insights from NAPA’s ship performance model and its voyage simulation tools, as well as Norsepower’s actual performance data. Using nowcast weather data from 2022 and specifications provided by Norsepower and SHI-ME, the digital twins developed by NAPA were able to simulate the performance of the tankers in selected sea areas.

Focusing on the annual voyages of six popular trading routes, the study evaluated the tankers’ estimated CO₂ reduction and potential fuel saving with NAPA Voyage Optimization and Norsepower Rotor Sails™, and compared these with using only NAPA Voyage Optimization.

Looking at results across all six routes, the study found an average CO₂ reduction of 19% when using NAPA Voyage Optimization alongside Norsepower Rotor Sails™, with NAPA Voyage Optimization contributing 10% of these emissions reductions. Using insights from the simulation, the study also explored how to predict vessel performance at the design stage, testing how the ship could handle varying sea and weather conditions.  

“This joint simulation project shows the significant potential for combining wind propulsion with voyage optimization for planet-positive impact. At a time when the industry is racing to comply with environmental regulations, digital solutions are enabling greater collaboration with stakeholders across the maritime value chain,” Pekka Pakkanen, Executive Vice President, NAPA Shipping Solutions, said.

“This joint simulation project was no different. Our findings are promising and can help bring much-needed clarity to help the industry meet its sustainability goals.”

 “SHI-ME’s vision is to deliver innovative and state-of-the-art vessels for shipping’s decarbonization. The Norsepower Rotor Sail™, NAPA’s knowledge of weather routing and SHI-ME’s expertise in tall-ship design are all vital pieces to materialize the vision of a greener industry. Looking at the findings from this study, we think the CO₂ emissions reduction figures exceed customers’ expectations,” Yuji Arai, Senior Engineer, Sumitomo Heavy Industries Marine & Engineering Co., Ltd. (SHI-ME), said.

Phase two of the research project (May 2023 onwards) is designed to build on phase one and enhance the performance of vessels with Norsepower Rotor Sails™. Using fleet data, the study will conduct advanced performance analysis to improve operational performance and explore new optimization strategies. The project is part of SHI-ME’s plan to develop a new proof of concept for wind-assisted ships, which will be equipped with Norsepower Rotor Sails™.

 “Norsepower’s mission is to lead shipping towards zero carbon emissions, so it has been an honor to work alongside top experts such as NAPA and SHI-ME. At a time of growing international regulatory and public pressure to save fuel and reduce the industry’s environmental impact, this performance data on the benefits of adopting clean technologies will give the industry the necessary confidence to invest in decarbonization,” Jukka Kuuskoski, CSO, Norsepower, added.

The project and its findings aim to help strengthen the business case for investing in wind-assist technology at a time when the industry is under increasing pressure to decarbonize.