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Mitsui O.S.K. Lines (MOL) is advancing the participation in the operation of a demonstration plant and the development of related technologies for Ocean Thermal Energy Conversion (OTEC). OTEC has the potential to become a foundation for the economic independence of island nations, not only for power generation but also through the utilization of deep seawater used in power generation to create local industries and living infrastructures. In this blog, we will introduce an overview of the project and our passion for the project, which includes an interview with the person in charge of OTEC project, in Part 1 and Part 2.

Why Mitsui O.S.K. Lines is Investing in OTEC

1. MOL announced its participation in the operation of the OTEC demonstration plant in Kumejima in April 2022. Partners in this endeavor include Saga University and the heat exchanger manufacturer Xenesys, Inc. (Xenesys). In the same year, OTEC in Kumejima was selected for Japan's Ministry of the Environment's "FY2022 Regional Co-Creation, Cross-Sector Carbon Neutral Technology Development and Demonstration Project", advancing technological verification for scaling up the equipment.

2. 
   Why is MOL, a shipping company, involved in OTEC? Yasuhito Hosomi, coordinator of the New Business Creation Team in the Well-being Life Business Division, who is in charge of commercializing ocean renewable energy projects such as OTEC and wave power generation, explains, "It's because we believe that it aligns with the concept of BLUE ACTION MOL that our company upholds, and that it can create a new vision of the world. Additionally, the shipping industry's performance is susceptible to market conditions, so we believe it's necessary to launch other foundational businesses for the company to contribute stably to society."

Yasuhito Hosomi, New Business Creation Team, Well-being Life Business Division (person in charge at the time of this interview)

According to Mr. Hosomi, when members of the New Business Creation Team learned about the Kumejima Model, they felt it was almost a "destined encounter". OTEC, as a stable power generation business, and its potential as a social infrastructure with the utilization of deep seawater for water and food production, was extremely attractive.

"We were deeply moved by the passionate commitment of the people at Saga University and Xenesys, who have worked hard to establish the technology. We are thoroughly captivated by OTEC. With OTEC and deep seawater as starting points, we aim to develop region-based infrastructure projects that contribute to people's well-being", says Mr. Hosomi.

The roles of Saga University, Xenesys, and MOL are clear. Saga University provides technical advice and works on technological development for OTEC efficiency and sea water desalination using OTEC. Xenesys is responsible for developing heat exchangers for larger power generation facilities and enhancing plant engineering. MOL, as mentioned earlier, is working on technological support and the construction of business models for the commercialization and scaling of OTEC.

Currently, Kumejima hosts a 100kW OTEC demonstration plant, and the goal is to achieve commercialization of OTEC on a 1MW scale around 2027, a world first.

Addressing challenges, such as revising deep seawater intake pipes, is crucial. The current plant in Kumejima uses two pipes with a diameter of 28cm (11") in the deep sea part, extending over 2km (1.2 miles), including the reef part, and pumps 13,000 tons of seawater per day. However, to further expand the surrounding industries, it is necessary to increase the water intake. "The large-scale intake pipe would account for the majority of the equipment cost, so we need to find ways to reduce the overall costs, including the water intake method", says Mr. Hosomi.

Deep seawater at a temperature of 8~9°C (46.4~48.2°F) flows through the white intake pipe, and surface seawater at a temperature of 26°C (78.8°F) flows through the black intake pipe

In aiming to scale up the power plant, technological innovation of heat exchangers is also needed. As introduced earlier, Kumejima's OTEC was selected for the Ministry of the Environment's project, and over three years, large heat exchangers are being manufactured and their performance verified, aiming for the commercialization of large-scale OTEC facilities.

"With a 1MW-class OTEC, 180,000 tons of deep seawater would be pumped daily, but it's expected that at least 100,000 tons of demand can be created in Kumejima. Kumejima Town is developing its own energy vision, and by 2035, they plan to cover 70% of the island's baseload power (power sources that can generate electricity stably day and night) with OTEC, and we want to meet that aspiration", concludes Mr. Hosomi.

Mitsui O.S.K. Lines' Philosophy of Sustainability

MOL has begun its foray into the realm of OTEC by participating in the demonstration project in Kumejima. However, the company has not yet definitively decided on the specific direction it will take or the business model it will construct in the future. Apart from potentially taking on the role of a power provider, there's also the possibility of becoming a facilitator of social and industrial infrastructure utilizing OTEC.

"Deep seawater can be utilized not only for OTEC but also in various fields such as fisheries, agriculture, and air conditioning. With all these possibilities, the challenge for MOL is to determine what kind of business model to create. Currently, our focus is on collaborating with the OTEC team from Saga University, Xenesys, and others, sharing their enthusiasm, and working towards popularizing the OTEC Kumejima model", says Mr. Hosomi.

Meanwhile, concrete steps are already being taken towards the wider adoption of OTEC, reflecting the unique sustainability development aspirations of a shipping company. One potential site of interest is Mauritius, an island nation off the southwest coast of Africa.

The area of the island of Mauritius is 2040 km², approximately the same as Tokyo

The Mauritian government has set a roadmap to increase the proportion of renewable energy to 60% by 2030, and OTEC is one of the technologies that can contribute to achieving this goal.

MOL, with the support of NEDO (New Energy and Industrial Technology Development Organization), conducted a study from May 2022 for about a year on the conditions for installing OTEC facilities. From December 2023, with additional support from the Ministry of Economy, Trade and Industry, MOL has started a new project to validate the feasibility of potential OTEC sites based on these study results. Moving forward, MOL plans to continue exploring the possibilities of utilizing natural energy and industries using deep seawater, not only in Mauritius but also in various countries worldwide.

In working towards creating and contributing to a sustainable society, OTEC offers a completely new concept, not limited to just power generation. It also supports the independence of people through the creation of new industries in surrounding areas, providing an innovative perspective, especially to companies involved in maritime activities like shipping companies.

Japan has the Capacity for OTEC Energy Equivalent to that of 25 Nuclear Power Plants

The ocean holds immense energy potential. The International Energy Agency - Ocean Energy Systems (IEA-OES) indicates that the theoretical annual generation capacity of the world’s ocean thermal energy is 10,000TWh (1 terawatt = 1 trillion watts).

In Japan, researchers estimate that in offshore areas within 30km (18.6 miles) and water depths less than 100m (328ft), there is a potential utilization of 156 billion kWh through OTEC. This equates to the electricity generated by 25 nuclear power plants (source: "The Power Hidden in Ocean Energy, Behind Japan's Lag – A Talk with Professor Kinoshita of the University of Tokyo" from The Nikkei newspaper 2011/12/7).

Furthermore, there are plans for the effective use of ocean renewable energy with the concept of "Floating Ship-Type OTEC Power Plant". These are power plants set up on ships floating at sea that generate electricity using both surface and deep seawater. However, floating OTEC plants would focus more on power generation, sending electricity ashore via undersea cables, rather than expanding surrounding industries.

Regardless, Mr. Hosomi believes, "As OTEC enters its full-scale proliferation phase, the opportunities for MOL to contribute will surely increase. We can offer our ocean business O&M (operation and maintenance) technology, especially for floating systems, and leverage our global network for information gathering and business expansion. This future is not far off; in fact, it has already begun."

Image of floating OTEC

Mr. Hosomi, who has been with MOL for ten years, belongs to a generation for whom 'environmental issues' have been a societal theme since childhood. Now, this generation is taking on OTEC- "My career background is in container booking sales and accounting, but I've always been aware of ocean renewable energy. Tackling environmental issues seems like a generational destiny, and it’s an exciting challenge to be involved in a new venture like OTEC."

Supporting Mr. Hosomi and his team as the secretariat is Nao Goka, a third-year employee in the New Business Creation Team. "When I was job-hunting, I heard that MOL was a challenging company. I truly think it's a company that embraces challenges, allowing young people like myself to commit to such an important mission", she says.

Well-being Life Business Division, New Business Creation Team Nao Goka

This journey stems from the ethos of "considering the world and society from the perspective of the sea", something not everyone can do. Oceans cover over 70% of the Earth's surface. MOL is expanding its field from a maritime enterprise to a social infrastructure enterprise, starting from the sea, and the venture into OTEC is a perfect embodiment of this approach.

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