Exploration of design space and optimisation of RoPax vessels and containerships in view of EEDI and safe operation in adverse sea conditions

The need for compliance with the stringent requirements of the Energy Efficiency Design Index (EEDI) in Phase II and III in the next few years and the everlasting objective to decrease fuel costs is expected to put new challenges to the designers of future ships and lead to design solutions with significantly reduced propulsion power, compared to ships currently in service. This gave rise to partly justified concerns by the maritime industry regarding the sufficiency of the propulsion power and steering devices to maintain manoeuvrability of future ships in adverse conditions, hence, justified worries about the safety of the vessels. In this respect, the present paper explores a significant part of the huge design space of RoPax vessels and containerships aiming at critically assessing the rationale of relevant EEDI regulations. This is accomplished by the development of a parametric multi-objective optimisation procedure, which enables the identification of designs with adequate power, while considering the EEDI framework as constraint and ensuring safe operation in adverse weather conditions. Resulting designs exhibit a reasonable, rationally supported balance between economy, efficiency and safety of the ship and the environment. The essence of the presented work was conducted in the frame of the EU funded project SHOPERA (2013-2016).