Dokuz Eylül Üniversitesi Denizcilik Fakültesi Dergisi, pp.109-133, 2021 (Peer-Reviewed Journal)
This paper introduces the basics of exergy-based sustainability assessment and the framework that should be shaped within the first stage. The sustainability assessment framework leads to sustainability indicators that are used to assist policymakers and decision-making processes. The literature review shows that the energy systems are suited to sustainability assessment with exergy based assessment tools and indicators from an environmental point of view. In this study, an exergy based sustainability assessment is carried out by using the exergy analyses results of an ORC (organic Rankine cycle) integrated waste heat recovery system on a 1,221 TEU container ship. The exergy analysis results are used to derive comparable and quantified exergetic sustainability indicators that indicate the sustainability level and further improvement potentials with the utilization of the proposed waste heat recovery system design. The assessment results show that the minimum waste exergy ratio is obtained with the value of 0.106 when R1234ze(Z) is used and the evaporating pressure is 3 MPa. R1234ze(Z) and R245fa working fluids show good environmental performance for the proposed system design. The maximum exergetic sustainability index value is obtained with the value of 8.435 when R1234ze(Z) is used and the evaporating pressure is 3 MPa.