Energy Conversion and Management, Vol.108, 190-201, 2016
Advanced exergy analysis of the Kalina cycle applied for low temperature enhanced geothermal system
In recent years, the possibility of using low temperature heat sources has been followed as a hot topic in different research and academic centers. In this regard, the Kalina cycle has been paid a lot of attention because of its promising features. Using the engineering equation solver (EES) software, conventional exergy analysis is carried out in this study for the Kalina cycle driven by a low temperature enhanced geothermal source. After validating the developed model for conventional exergy analysis, the advanced exergy analysis, i.e., splitting exergy destruction rate into endogenous, exogenous, avoidable and unavoidable parts, is performed to provide detailed information about improvement potential of the system components. The results of advanced exergy analysis show that the cycle has high potential for efficiency improvement. It is also revealed that the advanced exergy analysis gives the improvement priority first for the condenser, then for the turbine and the evaporator. From the conventional exergy analysis however, the exergy destruction calculated for the evaporator is higher than that for the turbine. (C) 2015 Elsevier Ltd. All rights reserved.