In a major step for maritime decarbonization, engine manufacturer Nanni and naval engineering firm ScandiNAOS have successfully developed and tested a high-speed, dual-fuel marine generator set utilizing a 70% methanol and 30% diesel blend. Engineered under the EU-backed LIFE MYSTIC project, the converted 6-liter John Deere platform maintained full power output while slashing carbon monoxide and hydrocarbon emissions by up to 99%, and NOx by 65% under classification oversight by RINA. This technical breakthrough provides a seamless, liquid-fuel alternative with built-in diesel redundancy, paving the way for the adoption of sustainable green methanol bunkering within the premium yachting and commercial marine sectors.
France | May 20, 2026 – In a milestone development for the alternative marine fuel sector, French engine manufacturer Nanni Industries, in partnership with Swedish naval engineering specialist ScandiNAOS AB, has unveiled its first high-speed dual-fuel marine engine operating on a blend of green methanol and diesel.
The breakthrough, developed under the umbrella of the European Union-backed LIFE MYSTIC project, successfully completed stringent laboratory testing under classification oversight. It marks a critical pivot for high-speed auxiliary power and gensets, proving that methanol’s application is rapidly moving beyond large, low-speed commercial commercial vessels into the premium yachting and smaller commercial marine sectors.
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The Technology: Re-Engineering the High-Speed Platform
The project centers on the conversion of a 6-liter John Deere-based engine platform, primarily configured for marine generator set (genset) applications. While the industry has seen widespread adoption of dual-fuel technology in medium- and low-speed segments, high-speed applications present unique challenges in fuel-mixing dynamics, transient response times, and thermal management.
To overcome these, Gothenburg-based ScandiNAOS developed a highly specialized, retrofit-capable dual-fuel injection kit. The conversion kit comprises both hardware and software modifications designed to seamlessly integrate into Nanni’s high-speed engine architecture:
- Methanol-Specific Engine Control Units (ECUs): Calibrated to manage the distinct ignition delays and energy densities of alcohol-based fuels.
- Redesigned Air Intake Manifold: Fitted with dedicated methanol injectors optimized for precise fuel-air charge mixing.
- Double-Walled Methanol Fuel Rail: Engineered to satisfy strict international maritime safety protocols, providing secondary containment to mitigate leak risks.
Fuel Economics and Built-In Redundancy
On an energy basis, the engine operates on an optimal blend of approximately 30% conventional diesel and 70% green methanol. The diesel acts as the pilot fuel to ignite the mixture under compression.
Crucially for vessel operators worried about alternative fuel availability, the system features automatic fuel fallback redundancy. If the methanol supply is depleted, the ECU initiates a seamless, mid-operation transition back to 100% diesel fuel without interrupting power generation or sacrificing electrical load continuity.
Empirical Validation: IACS Standards and RINA Testing
The converted high-speed genset underwent an exhaustive validation campaign at an independent testing facility. The trials were executed under the supervision of a surveyor from RINA (Registro Italiano Navale), adhering strictly to the International Association of Classification Societies (IACS) standards for progressive loading on marine generator sets.
The performance metrics and environmental yields verified during the testing phase confirmed the high potential of high-speed methanol combustion:
Performance & Load Flexibility
The engine successfully maintained its full rated power output in both pure diesel and dual-fuel modes. Depending on the specific load points, the proportion of energy derived from methanol fluctuated between 50% and 75%, demonstrating excellent transient performance during rapid load stepping.
Emissions Profile
The introduction of methanol yielded a dramatic reduction in harmful exhaust emissions across the majority of standard engine load profiles:
| Pollutant Indicator | Emission Reduction Level |
| Carbon Monoxide (CO) | Down by 95% to 99% |
| Unburned Hydrocarbons (HC) | Down by 95% to 99% |
| Nitrogen Oxides (NOx) | Down by 65% |
| Particulate Matter (PM) | Significantly lower baseline, clear combustion |
The Strategic Context: The LIFE MYSTIC Project
This technological breakthrough is a core pillar of the LIFE MYSTIC (Methanol for Yachting Sustainable Energy Transition Applied to Internal Combustion Engines) project. Launched in June 2024 with a total investment exceeding €4.8 million (60% co-funded by the European Union’s LIFE Programme), the project is spearheaded by the luxury shipyard Sanlorenzo.
The strategic alliance brings together a powerhouse of marine innovators:
- Sanlorenzo: Driving the vessel integration and converting traditional hull spaces to accommodate specialized methanol storage.
- Nanni Industries & Ranieri Tonissi: Developing and supplying the dual-fuel auxiliary gensets.
- MAN Engines: Developing the primary dual-fuel bi-fuel main propulsion engines.
The final objective of the 54-month initiative is the deployment of a groundbreaking bi-fuel superyacht (scheduled for 2027), featuring two high-speed MAN propulsion engines and two Nanni-ScandiNAOS gensets. The vessel is projected to slash localized greenhouse gas emissions by 150 tonnes of $\text{CO}_2\text{eq}$ per year and primary fossil fuel consumption by 700 MWh annually.
The Yachting Sector as a Green Catalyst
While the recreational and yachting sectors account for a modest 0.22% of global maritime greenhouse gas emissions, their high visibility and capital-intensive nature make them ideal testbeds for early-stage green fuel infrastructure.
Methanol holds a distinct operational advantage over alternative energy carriers like cryogenic liquefied hydrogen or ammonia: it remains liquid at ambient temperatures and pressures, allowing it to utilize existing bunkering footprints with relatively minor modification.
However, the commercial scaling of this Nanni-ScandiNAOS innovation faces a familiar chicken-and-egg bottleneck: bunker availability and regulatory gaps. In key yachting hubs, such as Italy, methanol is not yet fully codified within standard national bunkering frameworks for small-scale and recreational craft. Strategic initiatives like LIFE MYSTIC are actively engaging with port authorities, class societies, and marina associations (Assomarinas) to draft the safety, storage, and handling protocols necessary to secure a reliable green methanol supply chain.
By proving that high-speed internal combustion engines can safely, cleanly, and reliably burn a 70% methanol mix, Nanni and ScandiNAOS have delivered a commercial-ready technology that aligns with the International Maritime Organization’s (IMO) stringent decarbonization trajectories, positioning high-speed dual-fuel gensets as a highly viable path forward for sustainable marine power generation.
About the Partners
About Nanni
Founded in 1952, Nanni is a premier international manufacturer of marine engines and complete generator sets. The company delivers advanced propulsion and power solutions tailored across the maritime spectrum, from luxury recreational yachting to heavy-duty commercial vessels. Renowned for engineering reliability, high-power performance, and comfort-focused design, Nanni operates two state-of-the-art production facilities in France and Italy. Capitalizing on continuous investments in R&D and sustainable innovation, the company is deeply committed to driving the maritime sector’s transition toward low-emission and highly efficient propulsion systems.
About ScandiNAOS AB
Established in 2005 and headquartered in Gothenburg, Sweden, ScandiNAOS AB is a specialized naval architecture and marine engineering firm dedicated to pioneering sustainable vessel designs and advanced maritime transport systems. The company distinguishes itself through a holistic engineering approach, seamlessly integrating hull design, innovative propulsion systems, onboard energy management, and logistics optimization across the entire maritime value chain. As a recognized pioneer in decarbonization, ScandiNAOS has focused heavily on alternative fuel integration—particularly methanol—solidifying its position as one of the industry’s most experienced players in clean propulsion technology and emissions reduction.
Source: Nanni