This revised guidance provides shipbuilders and shipowners technical, regulatory and safety frameworks for integrating fuel cell power systems into new and existing vessels. 

Lloyd’s Register (LR) has released updated guidance for the installation of fuel cells on ships, offering shipowners and shipbuilders a comprehensive framework to support the safe deployment of alternative power systems.  

The July 2025 edition of Guidance Notes on the Installation of Fuel Cells on Ships incorporates recent regulatory updates and technical developments related to fuel cell technology in the maritime sector. 

Fuel cells powered by hydrogen or ammonia are viewed as options for achieving zero or near net-zero tank-to-wake emissions. LR’s updated guidance corresponds to the 2024 Rule changes for fuel cell installations and presents revised safety concepts for onboard integration. 

The guidance introduces two safety concepts for fuel cell spaces: emergency shutdown-protected fuel cell spaces and gas-safe fuel cell spaces. The gas-safe fuel cell space concept enables installation of fuel cell power systems within conventional machinery spaces and simplifies retrofitting, while ensuring compliance with fire protection, explosion prevention, and hazardous zone requirements. 

The document also addresses lifecycle considerations such as degradation, maintenance, and end-of-life performance, as well as operational topics such as power conditioning, thermal management, and inert gas purging. Specific recommendations are provided for installation locations, access, and environmental resilience. The updated guidance highlights the importance of risk assessments tailored to each installation, considering hazards including fire, explosion, toxicity, and electric shock. 

Thomas Bayer, Lead Specialist Fuel Cell Technology, Lloyd’s Register, said: “This new guidance is intended to provide detailed information for supporting the safe integration and reliable operation of fuel cell technologies on board ships.  

“By meticulously detailing the framework for safe integration and operation of fuel cell technologies, we are not just providing guidance for understanding and implementing of LR rules; we are fostering innovation and building confidence in the next generation of propulsion systems.”