Tokyo, Japan | December 3, 2025 – In a breakthrough moment for Japan’s maritime decarbonization efforts, Idemitsu Kosan Co., Ltd., one of the nation’s largest and oldest energy companies, has begun commercial supply of bio-blended marine fuel to oceangoing ships—becoming the first domestic oil major to provide such fuel for deep-sea vessels.
The initiative, launched in strategic collaboration with Kanematsu Corporation, marks a decisive shift in Japan’s bunkering landscape, establishing the country’s first fully certified supply chain for low-carbon marine fuels capable of serving international shipping lines.
Idemitsu has already begun supplying major clients, most notably Kawasaki Kisen Kaisha, Ltd. (“K” Line), and plans to deliver 5,000 tonnes of bio-blended marine fuel by March 2026, covering both domestic and international vessel segments. That supply volume is equivalent to fueling a 300,000-DWT class vessel for approximately 50 days, underscoring the scale and strategic importance of the rollout.
A New Era of Low-Carbon Bunkering for Japan
The supplied fuel blends conventional heavy fuel oil with FAME (Fatty Acid Methyl Ester)—a biodiesel produced by reacting used cooking oil with methanol. The result is a certified low-carbon fuel that offers an estimated 20% reduction in CO₂ emissions compared to standard marine oil without requiring ship engine modifications.
This advancement responds directly to the International Maritime Organization’s (IMO) tightening decarbonization mandates, including the 2030 greenhouse gas (GHG) reduction target and long-term net-zero ambitions.
By pioneering bio-blended bunkering for oceangoing vessels, Idemitsu becomes not only a fuel supplier but a crucial enabler of Japan’s compliance with global shipping decarbonization standards.
A Fully Integrated, Certified Supply Chain
The collaboration between Idemitsu and Kanematsu establishes a streamlined, end-to-end bunkering framework that leverages existing domestic infrastructure while meeting the rigorous sustainability requirements demanded by global shipping companies.
Defined Supply Chain Roles
| Partner | Key Role in Supply Chain |
| Idemitsu Kosan | Heavy oil supply and final supply/marine shipment of the blended fuel. |
| Kanematsu Corporation | FAME (Fatty Acids Methyl Ester) procurement. |
| Kanematsu Tank Terminal Co., Ltd. | Storage, precise blending, and quality confirmation of the FAME and heavy oil at its Kokura Depot (Kitakyushu City, Fukuoka Prefecture). |
After blending and certification checks, the fuel is loaded onto barges for ship-to-ship bunkering, providing oceangoing vessels with a drop-in low-carbon alternative compatible with existing fleet propulsion systems.
ISCC Certification: The Backbone of Credible Decarbonization
A central component of the initiative is the acquisition of ISCC (International Sustainability & Carbon Certification) by both Idemitsu and Kanematsu. This certification:
- Ensures traceable, sustainable raw materials across the entire supply chain
- Confirms the biodiesel complies with international GHG emission-reduction standards
- Provides shipping companies with the Proof of Sustainability (PoS) required for global environmental reporting
With major shipping lines now prioritizing certified fuels to meet their Scope 3 emissions requirements, the ISCC-certified supply chain significantly strengthens Japan’s competitiveness in the global bunker market.
Operational Validation: Cold-Climate Trials in Hokkaido
The commercial rollout follows a series of rigorous operational trials conducted on domestic vessels in Hokkaido from 2023 to 2024, a region whose harsh winters provided an ideal testbed.
Despite FAME’s known tendency to solidify in low temperatures, Idemitsu confirmed:
- No engine modifications were required
- Stable operation was maintained throughout
- No changes were necessary to vessel operating conditions
- Fuel performance remained comparable to conventional marine fuels
These findings addressed major technical concerns previously associated with FAME blends and cleared the path for full-scale commercial deployment.
Building Japan’s Next-Generation Marine Fuel Infrastructure
While the current supply utilizes Kanematsu Yuso’s existing marine terminals, Idemitsu has announced plans to eventually transition to using its own marine loading facilities, a move that would:
- Support higher supply volumes
- Reduce logistical constraints
- Establish a dedicated, scalable domestic low-carbon bunkering network
This positions Idemitsu as a long-term anchor for Japan’s maritime decarbonization framework.
Looking Beyond Biofuel: Idemitsu’s Ambition for E-Methanol Leadership
In parallel with bio-blend deployment, Idemitsu is accelerating research and infrastructure development for e-Methanol, a near-zero-carbon marine fuel produced by synthesizing CO₂ and green hydrogen generated from renewable energy sources.
E-Methanol is widely regarded as one of the most promising next-generation marine fuels, with many of the world’s leading shipping companies already ordering methanol-powered vessels.
Idemitsu’s strategy positions it to:
- Provide immediate emissions reductions through FAME bio-blends
- Develop long-term zero-carbon solutions via e-Methanol
- Build a domestic, sustainable fuel ecosystem aligned with global maritime trends
This two-track approach aims to secure Japan’s relevance in the rapidly evolving international bunker market while supporting shipowners in meeting increasingly stringent environmental regulations.
A National Milestone for Maritime Decarbonization
Japan’s shipping sector—home to some of the world’s largest carriers—faces mounting pressure to decarbonize. Idemitsu’s bio-blended bunkering program marks a pivotal turning point:
- The first domestic oil major to supply bio-blended fuel for oceangoing ships
- The first ISCC-certified, end-to-end biofuel bunkering chain in Japan
- The first step toward a future-proof sustainable marine fuel industry
As global shipping accelerates toward net-zero, Idemitsu’s initiative stands as a defining moment in Japan’s energy transition—one that blends heritage, innovation, and environmental responsibility to reshape the future of maritime fuel.
Idemitsu Kosan Co., Ltd.
Founded in 1940, Idemitsu Kosan is a leading Japanese energy company headquartered in Tokyo. We develop, manufacture, and market a wide range of energy and material solutions in partnership with a network of trusted partners and customers. Our business spans fuel oil, basic chemicals, high-performance materials, electric power, and renewable energy. Through continuous innovation and collaboration, we aim to create sustainable solutions that support industry and society toward a carbon-neutral future.
Source Idemitsu Kosan