BLOG

Mitsui O.S.K. Lines' (MOL) "Wind Hunter Project", which is striving to develop the ultimate zero-emission ship, has entered a new phase. The experimental ship "WINZ MARU" has moved its demonstration fields from Omura Bay in Nagasaki Prefecture to Tokyo Bay and has begun technological research to unload hydrogen carrier (MCH) produced during navigation for onshore use. While project members predict that "the true growing pains towards the commercialization of the Wind Hunter are yet to come," they are beginning to get a solid response to the realization of the world's first type of ship which no one has ever imagined before.

The Ultimate Zero-Emission Ship that Produces and Stores Hydrogen While Sailing

1. MOL’s Wind Hunter is a ship that navigates by capturing the offshore wind with sails. However, unlike any other ship MOL has ever built, it generates electricity by turning underwater turbines with the wind, electrolyzes seawater to produce hydrogen, stores the hydrogen carrier as MCH, and transports it to locations where energy is needed. This means it is a "hybrid plant combining offshore wind power generation and hydrogen production facilities". When there is no wind, it navigates using the stored hydrogen as energy. In other words, it is a ship that achieves the ultimate zero-emission with no greenhouse gas emissions at all.

2.  

3. MOL has already commercialized the "Wind Challenger", which uses a retractable rigid sail installed at the fore of the ship to harness wind power and assist the engine's propulsion. The Wind Hunter, as an "evolved version" of the Wind Challenger, navigates with multiple rigid sails erected on the deck.

4.  

5. Traditionally, the shipping industry has been tasked with transporting cargo/people between port A and port B. Hence, ships were structurally designed for such purpose. However, as seen in the purpose of the Wind Hunter, it is not only for transportation but also production, storage, and transportation of hydrogen energy, which is prompting the evolution of the shipping industry's business model.

Experimental Ship "WINZ MARU" Successfully Completes Concept Verification

To prepare for its practical application, the experimental ship "WINZ MARU" was first put into action. WINZ MARU is a small vessel- a pleasure yacht measuring 12m (approx. 39.4 ft) long. Various equipment was retrofitted, and the experiments began in 2021 at the testing fields in Omura Bay, Nagasaki, Japan.

First, the experiments focused on verifying the following in the "hydrogen production mode":
1. Whether the turbines (also functioning as propellers) could generate electricity by harnessing offshore wind
2. Whether water could be electrolyzed to produce hydrogen using the generated electricity
3. Whether the produced hydrogen could be stored

As for the "hydrogen consumption mode", the experiments aimed to verify:
1. Whether the stored hydrogen could be extracted for use as the ship's energy source
2. Whether electricity could be generated via fuel cells
3. Whether the yacht could be propelled using an electric propeller

The results showed that wind power generation could achieve 1.0-kilowatt, hydrogen production via electrolysis could produce about 1.0 liter per minute, and in consumption mode, the hydrogen-powered fuel cells could generate approximately 1.0 kilowatt, enabling the yacht's propulsion with an electric propeller.

Mr. Kentaro Shima, project leader and General Manager of the Technology Research Center at MOL, commented, "The experiments in Omura Bay successfully verified the concept of hydrogen production, storage, transportation, and utilization. We also identified measures to improve energy efficiency by reviewing the plant and ship systems, thereby clearing the so-called starting stage."

(It cruises using wind energy, while at the same time generating electricity by underwater turbines. By electrolyzing pure water made from seawater, it produces hydrogen. By causing a chemical reaction of hydrogen and toluene, it creates Methylcyclohexane: MCH, which is one of the hydrogen carriers, and stores that in MCH tanks onboard. The dehydrogenated hydrogen from this MCH is converted and used to propel the ship.)

            Mr. Kentaro Shima, General Manager of the Technology Research Center, Mitsui O.S.K. Lines (at the time of the interview in May 2024)

Experiment Moves from Omura Bay to Tokyo Bay with a Focus on "Creating the Hydrogen Supply Chain"

The experiments using WINZ MARU moved to the next stage in October 2023.

The Wind Hunter Project was selected for the Tokyo Metropolitan Government's "Tokyo Bay eSG Project: Cutting-edge Renewable Energy Priority Project", and the testing fields moved from Omura Bay to the Central Breakwater area in Tokyo. The Tokyo Bay eSG Project aims to explore the "realization of a sustainable city where nature and convenience blend", using the Tokyo Waterfront City area (Daiba, Aomi, Ariake) which overlooks Tokyo Bay, and the adjacent Central Breakwater area. In addition to Wind Hunter, other priority projects include the development of flying cars and the establishment of autonomous driving technology using 5G.

The main theme in Tokyo Bay is to experiment with various technologies to unload and supply the hydrogen energy produced and stored by Wind Hunter to onshore facilities. This means building a complete hydrogen supply chain from production to utilization and confirming the possibility of collaboration with related businesses. In May 2024, it was publicly showcased for the first time at "SusHi Tech Tokyo 2024*", hosted by the Tokyo Metropolitan Government, drawing significant attention from both stakeholders and the general public.

*An initiative hosted by the Tokyo Metropolitan Government to promote "Sustainable High City Tech Tokyo = SusHi Tech Tokyo", which aims to create "sustainable new value". It seeks to generate innovations from Tokyo to address global urban challenges and present future urban models.

The WINZ MARU and its interior, unveiled at SusHi Tech Tokyo 2024

Adopting MCH, a hydrogen carrier, for Hydrogen Storage and Transportation: Considerations for Onshore Facilities

When Mr. Shima talks about the "utilization of MCH for Wind Hunter", he refers to advantages compared to other hydrogen carriers.

There are several hydrogen carriers, for example, "liquefied hydrogen" and “Ammonia(NH3)”, which are some of the more popular ones. However, it requires significant energy to process under on-board conditions, and storage also　requires specific structure and insulation, etc.
In contrast, Wind Hunter aims to use the "methylcyclohexane (MCH) method", which involves combining hydrogen with toluene for storage and transport. When hydrogen is combined with toluene, it becomes MCH. Hydrogen can be extracted   from MCH and toluene is also collected. This process is also known as the "Organic Hydride Method".

MCH offers several advantages over other hydrogen carriers:
1. It remains liquid at room temperature and pressure
2. It has a higher hydrogen weight density than hydrogen storage alloys
3. It can be used for existing gasoline infrastructure as-is
4. It requires less energy to convert gaseous hydrogen to MCH
MCH is also used as an industrial raw material in products like paints, adhesives, and correction fluid solvents. 

In the initial experimental stage of WINZ MARU in Omura Bay, the hydrogen produced was originally stored in hydrogen storage alloys and MCH trials were also done. When there is no wind at sea and the ship needs to use hydrogen, MCH stored in dedicated tanks is processed by a dehydrogenation device to extract hydrogen. The hydrogen fuel cells then generate power to turn the propellers, enabling navigation.

Verification Vessel by 2027 and Commercial Vessel by 2030

The Wind Hunter as a project is still in its experimental phase, but there is already a roadmap leading to "Stage 2 (Verification Vessel)" and "Stage 3 (Commercial Vessel)".

In Stage 2, targeted for completion by the end of FY2027, a "medium-sized hydrogen production vessel will be constructed to verify the economic feasibility and safety of a large commercial vessel." Specifically, this involves building a ship about 60~70m (approx. 196.9~229.7 ft) long and includes:
1. Developing plant technology for efficiency
2. Key component efficiency evaluations such as numerous sails interference, water electrolysis, etc
3. Safety assessment as a ship

Following this in Stage 3, targeted for around 2030, the construction of commercial vessels will begin. These commercial vessels will be over 200m (approx. 656.2 ft) long. "There are still many technological challenges, such as developing technology to produce pure water from seawater for hydrogen production and developing underwater turbines for power generation that operate optimally at the anticipated ship speed," says Mr. Shima.

The conceptual plan envisions the commercial vessels as unmanned ships in the future. They will autonomously head towards areas with favorable wind conditions, navigate and produce hydrogen there, and then automatically proceed to designated locations. Upon arrival at port, drones will carry the mooring lines to shore, MCH will be unloaded, toluene will be replenished, and the ship will move to the next optimal wind area to resume hydrogen production.

One of the necessary technologies for this is the "ability to hunt the wind". This involves a "Long-Range and Real-Time Wind Condition Measurement Device Doppler LiDAR  ", which can visualize wind conditions in real-time by emitting laser light into the atmosphere and receiving scattered light from aerosols (dust and particles) in the air. The device can detect wind direction and speed within a 15km (approx. 9.3 miles) radius, and based on this data, the ship can “hunt” the optimal wind. Verification of observation accuracy and practical challenges are currently ongoing with a ship on the Tokyo-Fukuoka trading route.

Comments from Mr. Shima
"Creating a Ship Like No Other in the World
-the Joy of Turning Imagination into Creation-"

Mr. Kentaro Shima, General Manager of the Technology Research Center, Headquarters of Technological & Digital Transformation, Mitsui O.S.K. Lines

"Since joining MOL, I have been involved not only in shipbuilding but also managing the vessels, dismantling and selling decommissioned ships. What these tasks have in common is that they all involve 'existing technology'.

However, the Wind Hunter Project is a challenge to create a 'zero-emission ship'. Can you imagine the excitement I feel working on this project together with not just our colleagues, but also various companies and research institutes?

Since the project started in 2020, we have conducted numerous experiments and verifications, step by step, without a textbook to guide us. Despite various efforts, when our small yacht finally sailed smoothly and produced hydrogen, we experienced firsthand how powerful and inspiring the transition 'from imagination to creation' can be.

In the context of mountain climbing, the development of Wind Hunter technology is still around the second or third station. The true growing pains are yet to come. However, we project members are already well acquainted with the joy of creation and know we will only be moving forward.”

(This article is based on interviews conducted in May 2024.)