Comparative efficiency assessment of a multi-flash integrated system based on three efficiency definitions

This paper deals with energy and exergy analyses of a multi-flash integrated system and studies three efficiency definitions for system assessment. In this regard, a comparative performance evaluation is conducted to investigate the effects of using these energy and exergy efficiencies on the assessment of a triple-flash integrated system with an electrolyzer. Parametric studies are conducted to investigate the effect of rise in the ambient temperature and geothermal source temperature on these energy and exergy efficiencies. The results show that the efficiency definition plays a critical role as the efficiency value differs from one definition to another. Increasing the ambient temperature decreases both energy and exergy efficiencies based on the first definition, but increases them based on the second and third definitions. An increase in the geothermal source temperature reduces both energy and exergy efficiencies based on the first definition, but increases them based on the second and third definitions of efficiencies. The energy and exergy efficiencies of the overall system based on the third definition are found to be increasing from 0.6 to 2.2% and 6.5 to 47.29%, respectively. Copyright , Oxford University Press.