Sumitomo, NAPA, Norsepower See Bright Future for Rotor Sails

Partnerships will be key to decarbonizing shipping, as each participant brings different strengths and knowledge sets to bear on the problem. A recent collaboration between NAPA, Norsepower and Sumitomo Heavy Industries shows the benefits of a partnership approach. In a recent study, the three companies revealed the potential fuel savings achievable with a combination of rotor sails and weather routing on a primary trade lane. On the right route, the top-line number is a remarkable 28 percent, enough to make a notable difference in the bunker fuel bill. To learn more, The Maritime Executive caught up with Naoki Mizutani, Managing Director, NAPA Japan; Jukka Kuuskoski, Chief Sales Officer, Norsepower; and Akihiko Masutani, Director of Business Development Division, Sumitomo Heavy Industries.

The findings of the NAPA-Norsepower-Sumitomo study are remarkable. Can you tell us about how your partnership formed and the idea for this study came about? 

Masutani: The idea for the project started over a meeting between Mr. Mizutani and myself, when we saw an opportunity to join forces to better understand how digital and clean technologies can work together. We knew that this project was a formidable opportunity to join forces. More specifically, our objective was to explore digital transformation (DX) and green energy transformation (GX) to see how we can deliver optimal navigation with wind propulsion systems from a shipbuilder’s point of view. With the support of the Japanese Government fund for DX/GX, we set out to start the project in December 2022.

Mizutani: With wind propulsion technologies becoming increasingly popular, our aim was to bring our diverse expertise together to answer a crucial question: what emissions reductions could be achieved by combining wind propulsion and voyage optimization? Now that the first phase of the project has provided valuable answers, in phase two we are turning our attention to an equally important matter: how we can make those results even better in the future.

Kuuskoski: Norsepower’s reason for existence is to push the shipping industry towards zero carbon, so when NAPA and Sumitomo – who share our vision for a sustainable energy future – reached out to us for collaboration, we were honored and delighted to join. The results of this study clearly illustrate the impact we can make by working together and combining existing technologies in maritime transport to save fuel and the planet.

Were you surprised at the scale of the positive results? 

Mizutani: We’ve known that independently, both voyage optimization and rotor sails can significantly reduce GHG emissions and fuel consumption. It also made sense that wind propulsion systems would achieve optimal results when combined with weather routing technology that enables the ship to make the most of wind conditions. So, it was a natural fit to combine the two technologies to reduce emissions even further. This project’s unique contribution was to put a validated figure on this potential: up to 28% emissions reductions on average.

To shed a bit more light on the project, the study focused on annual voyages of six popular trading routes for a SHI-ME tanker. Using nowcast weather data from 2022 and specifications provided by Norsepower and SHI-ME, digital twins developed by NAPA simulated the tanker’s performance in those selected sea areas. We evaluated the estimated CO2 reduction and potential fuel saving that could be achieved by combining NAPA Voyage Optimization and Norsepower rotor sails, and compared those with using only NAPA Voyage Optimization.

We 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. The project also showed the most potential savings on the Atlantic route between New York and Amsterdam, where the combination of four Norsepower rotor sails and NAPA’s Voyage Optimization could deliver average emissions reductions of 28%. NAPA Voyage Optimization’s contribution to this was estimated at 12%.

This study gives owners and operators a clearer picture of a ship’s future performance and operations, even before the system is installed on board. At a time of fast-paced technology and regulatory change, we hope that we can give owners more certainty about the exact benefits of their investments.

How have the results of the NAPA-Norsepower-Sumitomo study been received by shipowners? Are you hearing more expressions of interest based on the positive outcome? 

Mizutani: Many companies have expressed an interest to learn more about the potential return on investment (ROI) of adopting wind-assisted propulsion and voyage optimization for specific ships and routes in their fleets. Positive discussions are ongoing, and we are helping these shipowners and other stakeholders predict their ROI by using realistic voyage simulations, taking into account their ships’ specific characteristics and operational conditions.  

Kuuskoski: Shipowners that we have communicated with are optimistic about rotor sail technology and this is indicated by our fast-growing sales funnel with several exciting installation projects in the pipeline. This comes at the right time, especially as the industry is under growing pressure to accelerate its decarbonization with developments including the recent agreement at MEPC 80, CII and the EU ETS. In addition to this, studies like the one by UMAS on “How can international shipping align with 1.5°C?” show that most of the absolute emission reductions required by the industry this decade can be unlocked using solutions we already have, including voyage optimization and wind propulsion.

Can you tell us a bit about the next steps for the project?  

Mizutani: We started Phase Two of the project in May this year, with the aim to build on our findings from Phase One and enhance the sophistication of optimal design methodology and our voyage optimization models, factoring in vessels with Norsepower Rotor Sails. Specifically, we are aiming to develop a rotor sail algorithm and improve our voyage optimization models for better support during the ship design and operational phases. Combining expertise and data from all three parties, the aim is to better predict and improve vessel performance as early as the design stage.

Masutani: Using fleet data, the project will investigate ways to improve vessel design to make the most of their wind-assisted systems. For example, the project will conduct a more advanced analysis of lateral forces and movement of the hull and develop new optimization strategies for improving operational performance. Typically, ships are designed to deliver optimal performance in static wave conditions or in the absence of waves, but wind-assist vessel designs need to be adapted for the stronger wind conditions in which they will be operated. Therefore, SHI-ME’s ship design process will also include greater consideration of ship stability in heavy weather in addition to the traditional static wave calculations already used for many vessel designs.

What are your predictions for the future of wind-assisted propulsion in the coming years? 

Kuuskoski: We see a bright future with the promise of technological innovation in sustainable energy. Our new production hubs will have the capability to produce hundreds of Norsepower Rotor Sails per year and we have our eyes set on delivering fleet-wide installations. The time for the industry to save fuel and safeguard the planet is now, and decisions made today will go a long way in enabling shipping to achieve its longer-term decarbonization ambitions. Of course, we won’t be doing it alone and will call on the support of stakeholders across the maritime value chain, from ports to digital solutions providers, shipowners and charterers.

Masutani: Our exploration of DX/GX has only just begun. Once we have established technology based on wind-assisted propulsion, we will challenge ourselves to take the performance of those vessels to new heights through further collaboration.