Comprehensive evaluation of marine waste heat recovery technologies based on Hierarchy-Grey correlation analysis

In this study, comprehensive evaluation of the technologies on waste heat recovery technologies for maritime applications has been carried out. We have focused our research on exhaust gas turbine system (EGT), thermodynamic organic rankine cycle (RC), Kalina cycle (KC) and thermoelectric generators (TG), which are the most appropriate and most up - to - date techniques for recovering power from marine engines. Each technology has its own advantages and disadvantages, so the comprehensive evaluation of these technologies is essential to accurately determine which technology will be applied to which target. This belongs to the multi-criteria decision (MCDM) process. The combined assessment methodology, consisting of gray correlation and analysis hierarchy processes, has been applied to evaluate four waste heat recovery techniques in terms of technical, economic, social and environmental aspects. According to the comparison results, the exhaust gas turbine system has been evaluated as the most promising technology among the various WHR technologies that can be applied to marine engines. Sensitivity analysis suggests that if investment cost of TG falls to about the same level as the one of EGT, TG could be the best method among these technologies. Reduction of investment cost of TG technology could be realized by development of low cost thermoelectric material. We have analyzed the correlation between each cost through DOE analysis and investigate the effect of individual costs on the total cost.This work helps in identifying the most suitable heat recovery technologies for marine engine.