Implementation of natural refrigerants on cruise ships. A review of rules and regulations from two Classification Societies

Abstract

This report delves into the challenge of implementing heat pumps, refrigeration systems and chillers (vapour compression systems) that use natural refrigerants, in the maritime sector. The first part gives a context, introducing the international organisations aim to reduce greenhouse gas emissions from the shipping industry, and defining the topic of refrigerant selection. The documents on safety requirements for vapour compression systems onboard, issued by the classification societies Lloyds Registers and DNV, are then summarised. The focus is on the implications for systems using natural refrigerants. It is found that a "case-to-case" evaluation of almost all these systems must be applied. In the last section the communication with the classification societies is summarised. The goal is to contribute to clearer and more standardised requirements on the use of natural refrigerants, to facilitate their safe implementation, environmental-friendly and long-term compliant maritime refrigerants.