Taking the Cruise Towards Sustainability: A Multidimensional Assesment Approach for the Introduction of New Cruise Ship Cabin Technologies

Abstract

The shipping industry is currently responsible for about 3% of the total greenhouse gas emissions, making the steady growth of that industry a challenge concerning the fight against climate change. Nonetheless, the International Maritime Organization agreed on the target of cutting CO2-emissions by not less than 50% by 2050. With cruise ships having one of the largest ‘per average ship’ fuel consumption, they have been especially subject to sustainability discussions. Research and development have so far focussed mainly on the improvement of propulsion system of ships. Though, since on today’s cruise ships there are up to 3,500 passenger cabins, their material composition, supply structures as well as their usage contribute significantly to the environmental impacts of the ships (~25% of the used energy make up the hotel load, therefore, the lodging of guests and staff). The EcoCab project (funded by the German Federal Ministry of Economic Affairs and Climate Action) hence aimed at the development of sustainable cruise ship cabins addressing not only the environmental impacts but also social and economic aspects in a holistic approach. Together with the German MEYER WERFT, a big player of the cruise ship building industry, a sustainability assessment framework for the design of cruise ship cabins was set up. This framework not only addresses different technical design options but also considers the stakeholder interests (i.e. passenger and shipping company needs) with view on environmental, economic and social matters. A focus was put particularly on the early technical development stage in which usually high uncertainties regarding potential impacts still persist. For each sustainability dimension comprehensive studies were performed covering the life cycle assessment (LCA) and life cycle costing (LCC) along the cabin design process as well as the social acceptance using interviews with passengers and experts from the industry. In order to support the decision-makers in the technological design process, the results for eleven different technology and design configurations were combined within a multi-criteria decision analysis (MCDA). The results to be presented include the transferable assessment framework for the maritime sector as well as outcomes of the LCA, that show the potential reductions of the total environmental load of different options (e.g. a reduction of ~38% for the introduction of the new heating, ventilation and air conditioning system (HVAC) and ~8% for photovoltaic-modules and smart windows). Within the MCDA, indicators from all dimensions were combined, showing that the introduction of new HVAC and energy supply technologies, a methanol-based propulsion system and cradle-to-cradle materials performed best overall compared to the state-of-the-art cabins. Even though legal and technical matters could be regarded negligibly, future studies should further assess their impact on the transfer of sustainable options into practice.