The 2026 Lloyd’s Register report on the retrofit of marine engines highlights the technical milestones achieved in 2025, including the first successful conversion of a two-stroke engine to methanol and trials of methanol-methanol blends. These innovations come despite regulatory uncertainty surrounding the International Maritime Organization’s (IMO) Net Zero Framework, which is delaying the adoption of zero or very low emission fuels and hindering shipowners’ investments.
Every year, the British classification company Lloyd’s Register reviews the global market for retrofitting merchant ship propulsion systems. The 2025 report shows a steady increase in these major interventions, as well as significant technical milestones. For example, the first successful conversion of a two-stroke engine to methanol on the Cosco Shipping Libra container ship demonstrated the feasibility on large engines and serves as a model for other vessels. Methanol is also emerging as a complementary fuel, with trials of methanol-methanol blends conducted by Maersk and validations by equipment suppliers on both two-stroke and four-stroke engines.
These technical innovations are happening while the vote on the Zero Net Framework (NZF) of the IMO has been postponed, delaying the adoption of incentives for zero or very low emission fuels (ZNZ). This uncertainty is impeding shipowners’ investments. However, Lloyd’s Register points out that this postponed demand could be concentrated in the coming years. With more conventional vessels being built today, a significant number will need to be converted to achieve carbon neutrality goals by 2050, putting strong pressure on future capacities and costs.
Conversion activities and preparatory retrofits have progressed despite shipowners’ caution. Projects such as the retrofit to methanol on the Cosco Shipping Libra vessel by Everllence, formerly Man Energy Solutions, have been validated, confirming performance under real conditions. Stena Line has continued converting its Superfast VII and VIII ferries to methanol and e-methanol, preparing for future adoption of green fuels. Meanwhile, so-called “bridge” retrofits have continued to develop, optimizing engines, propulsion, and control systems to reduce fuel consumption and emissions.
Liquefied Natural Gas (LNG) remains an interesting transitional fuel thanks to its existing infrastructure and the availability of dual-fuel engines, with improvements targeting methane slip reduction. Methanol complements LNG, with a higher energy density requiring adjustments in injection and supply. Current regulations, including the IGF code and IMO provisional guidelines, already regulate its use, facilitating progressive adoption.
According to LR experts, the retrofit market continues to structure itself, with increasing technical credibility and a wider range of offerings. Adoption of the NZF could accelerate conversions and reduce costs through economies of scale. In its absence, regional and national initiatives are expected to sustain demand in a fragmented manner. In the long term, the majority of conventional ships built today will need to be converted or replaced to meet emission reduction requirements. Lloyd’s Register emphasizes that the most effective solution is to design ships from the start that are compatible with ZNZ fuels, reducing the need for complex conversions and facilitating the achievement of carbon neutrality goals by 2050.
(Short Context: The Lloyd’s Register report highlights the advancements in retrofitting marine engines achieved in 2025 despite regulatory uncertainties.) (Fact Check: Methanol is being considered as a complementary fuel for marine vessels, along with LNG, to reduce emissions and meet future environmental goals.)
