NYK Cruises Co., Ltd., a member of the Nippon Yusen Group, has announced that its cruise ship Asuka III reduced annual CO₂ emissions by approximately 1,300 tonnes over the 12-month period from 1 July 2025 to 30 June 2026 through the use of LNG as a fuel in place of conventional heavy fuel oil (heavy oil A) of equivalent calorific value.

According to NYK Cruises, the 1,300-tonne CO₂ reduction figure is equivalent to the annual household emissions of approximately 530 average Japanese homes, based on data from Japan’s Ministry of the Environment, which places average annual CO₂ emissions per household at 2.47 tonnes of CO₂ per year.

The calculation was carried out using guidelines from the Intergovernmental Panel on Climate Change (IPCC) and Japan’s Ministry of the Environment. NYK Cruises explained that the methodology involved comparing the fuel volumes required to generate equivalent calorific output and their respective CO₂ emissions, noting a conversion factor of approximately 1 tonne to 1.3 kilolitres of heavy oil A.

NYK Cruises said the Asuka III incorporates technologies designed to reduce environmental impact, with LNG serving as one of the vessel’s fuels.

The company described the initiative as part of the broader NYK Group’s decarbonisation strategy, which is aimed at achieving net-zero emissions by 2050.