Thermodynamic and Exergoeconomic Analysis of Combination of Single-Flash Geothermal Power Cycle with Kalina and ORC with different Organic Fluids

In this paper، single-flash geothermal power cycle with Kalina and ORC combined cycles are examined from energy، exergy and exergoeconomic viewpoints. Isobutane، isopentane، n-butane، n-pentane and R123 are used as working fluids in ORC. Exergoeconomic analysis is performed using the SPECO method. The results show that geothermal power cycle-ORC with R123 and n-pentane have the highest value of first law efficiency among considered combined cycles whereas geothermal power cycle-Kalina has the lowest unit cost of power produced by turbines. According to optimization of the combined cycles، the minimum unit cost of power produced for the geothermal power cycle-Kalina is 8. 63% lower than the unit cost of power produced in the maximum first law efficiency. Also the geothermal power cycle-Kalina with different ammonia concentration combined cycle has the lowest cost rate associated with exergy destruction. Finally parametric study is done and the effects of various parameters on exergoeconomic parameters of combined cycles are investigated.