The maritime industry is entering a period of unprecedented transformation as shipowners seek practical pathways to reduce greenhouse gas emissions while maintaining safe, reliable, and commercially viable operations. Retrofitting existing vessels with alternative fuel systems and energy-saving technologies has emerged as a key enabler of fleet decarbonisation, supporting compliance with evolving international and regional environmental requirements.
These Guidance Notes provide a comprehensive framework for the retrofit of ships with alternative fuels, including LNG, LPG, methanol, ethanol, ammonia and hydrogen, together with energy-saving technologies such as Wind Assisted Propulsion Systems (WAPS) and Air Lubrication Systems (ALS). The document brings together technical, safety, classification and statutory considerations into a structured approach that supports the successful delivery of retrofit projects.
The guidance addresses the full retrofit lifecycle, including feasibility assessment, stakeholder engagement, shipyard selection, project management, risk assessment, design approval, construction, commissioning, sea trials, certification and in-service operation. Particular emphasis is placed on the application of risk-based principles, alternative design approval processes and Lloyd’s Register's Risk Based Certification (RBC) methodology to ensure that novel technologies achieve an equivalent level of safety while meeting applicable regulatory expectations.
Developed from Lloyd's Register's experience across alternative fuel and decarbonisation projects, these Guidance Notes support shipowners, operators, designers, shipyards, equipment manufacturers, and Administrations in navigating the technical and regulatory challenges associated with modern retrofit programs. By promoting a consistent and practical approach, the guidance helps enable the safe adoption of low- and zero-carbon technologies across the global fleet.