Cooling Fluids and Ambient Temperature: Sensitivity Performance of a Container Ship Organic Rankine Cycle Unit

The objective of this paper is to design organic Rankine cycle units that are cooled by air or seawater and show the changes in net power output and power requirement as the ambient air temperatures change both geographically and seasonally. The organic Rankine cycle unit uses the available waste heat from the scavenge air system for a 4,100 TEU container ship. This work uses a two-step single objective optimisation capable of selecting 14 design characteristics of the organic Rankine cycle unit and with the aim of minimising the vessel’s CO2 emissions. The work contributes to the study of off-design operation and different cooling fluids for marine waste heat recovery systems. The results show that the organic Rankine cycle unit is more adaptable to ambient air temperatures when using seawater as a cooling fluid while air is an attractive option for extremely low ambient temperatures