Techno Selection Approach of Working Fluid for Enhancing the OTEC System Performance

Conversion of Ocean Thermal Energy (OTEC) is an electrical generation process that uses minor temperature variations among hot shore water and cool deep sea water. The main goal of the study is to determine the most suitable operating fluid to provide a high performance of the OTEC process. Three groups of organic fluids: wet, dry, and IOS entropic fluids, as working fluids, are investigated in this study in converting the low-grade energy of the OTEC system. A mathematical model is constructed for this purpose using the temperature gradient for the Mediterranean Sea in Egypt as a case study. The results indicate that the refrigerant R134a has a significant effect on the OTEC system efficiency with an efficiency of 2% at a constant pressure and 2.73% at a constant temperature, and on the price and the environmental issues, which all make it the optimum cooling fluid for the OTEC cycle.