Frederikshavn, Denmark | December 9, 2025 – Global engine designer Everllence (formerly MAN Energy Solutions) has achieved a significant milestone in maritime decarbonization, confirming the successful running of its 21/31 dual-fuel four-stroke engine on ethanol across all load points at its test facility in Denmark.
The successful trial not only strengthens the technical viability of ethanol but also positions Everllence’s small-bore engine platform as a highly fuel-flexible solution, directly addressing the market uncertainty surrounding long-term fuel pathways.
Technical Breakthrough: Higher Ethanol Share Than Methanol
The core of this achievement lies in the 21/31DF-M (Dual-Fuel Methanol) platform, which was already a commercial success as the world’s first small-bore, four-stroke methanol-burning GenSet, launched in 2024.
Rasmus Frimann Nielsen, Senior Manager and Head of Four-Stroke Small-Bore Engineering, highlighted a key operational metric: “During testing, we even managed to expand the ethanol fuel-share compared with methanol.” This indicates strong combustion stability and efficiency improvements for the alcohol platform, paving the way for maximum carbon reduction.
- Fuel Flexibility Confirmed: The test proves the 21/31 architecture can handle both methanol and ethanol, two of the most discussed low-carbon alcohol-based fuels.
- Rapid Development Cycle: The ease with which the methanol platform was adapted for ethanol validates Everllence’s design approach, which factored in the “steadily growing interest in ethanol from the market.”
Market Implications: Ethanol Joins the Multi-Fuel Strategy
The marine industry is undergoing a period of intense flux, with shipowners hesitant to commit billions to single-fuel vessels amid evolving regulations such as FuelEU Maritime, and infrastructure gaps. Everllence’s validation of the 21/31 engine for ethanol provides a vital new option for auxiliary power and diesel-electric propulsion systems.
Lars Zimmermann, Director of Sales & Promotion, Marine GenSets, acknowledged the market’s dilemma: “We keep a close eye on the market and see some uncertainty among our customers regarding which fuel strategy they should pursue.“
- De-risking Investment: By offering ethanol capability on the same proven platform, Everllence enables shipowners to adopt a multi-fuel, future-proof approach, mitigating the risk of regulatory or supply chain “lock-in” to a single fuel.
- Scalable Green Fuel: Bioethanol, produced from biomass like sugarcane or corn, offers a well-established, scalable supply chain from the land transport sector. While its lower energy density requires larger storage volumes, its clean-burning properties and potential for deep decarbonization make it an attractive pathway, especially for the short-sea and ferry sectors.
The Bunkering Call-to-Action: Legislation and Demand
While the technology is now validated, the story highlights that the bunkering sector and regulators must catch up to support ethanol’s widespread adoption.
Lars Zimmermann stressed the next crucial steps: “Now we need legislation in place that considers the case of ethanol as a viable fuel source, as well as developing a requisite market demand.“
This is a direct signal to the International Maritime Organization (IMO) and regional bodies like the EU that engine technology is moving faster than regulatory frameworks. Clear standards are needed to govern the handling, storage (due to its hygroscopic/corrosive properties), and bunkering procedures for low-flashpoint ethanol before the bunker supply chain can invest in dedicated infrastructure.
Conclusion
Everllence’s latest test thrusts ethanol firmly into the conversation alongside methanol and ammonia as a technologically proven low-carbon fuel. For the bunker market, this represents a major future opportunity: a proven engine platform that can potentially open up new fuel streams (ethanol) in ports where methanol infrastructure may be slow to develop.
The industry’s focus must now shift to standardizing its use and incentivizing the bioethanol supply chain to secure a stable and cost-competitive green molecule for shipping.
About Everllence
Everllence (formerly MAN Energy Solutions) is a global leader in decarbonization and propulsion systems for shipping, energy, and industry. Headquartered in Germany, the company’s portfolio spans advanced engine technology, climate-neutral fuel retrofits, carbon capture, hydrogen systems, and industrial heat pumps. Through its subsidiary Quest One, Everllence also supports green hydrogen production at scale. With 15,000 employees across more than 140 sites worldwide, Everllence’s service arm, Everllence PrimeServ, provides global after-sales support.
Source Everllence