Thermodynamic and Thermo-Economic Analysis of a Solar-Integrated Double-Turbine Kalina Cycle for Varying Solar Flux Conditions

Abstract

Kalina cycle is established as a reliable low-grade energy cycle working on solar, geothermal, and other waste heat recovery sources. This work aims to develop a novel methodology for optimizing a Kalina cycle according to the solar irradiation. A comprehensive analysis of performance is conducted by varying the parameters of the Kalina system, modeled with high- and low-pressure turbines. The present work implements and analyzes the performance of a multi turbine Kalina cycle with cylindrical parabolic collectors for energy input at different time, on a particular day, for a location. The proposed cycle is modeled to simulate the working. The dependency of parameters—separator pressure, concentration of ammonia in boiler, intermediate separator temperature and vapor fraction at condenser side turbine exit—on the system performance is investigated. Optimization is conducted using genetic algorithm with net power as objective function for different solar irradiations. The optimized power values are 282.62, 246.75, 222.31, and 180.0 kW for solar influxes 507.7, 461.8, 413.9, and 321.0 W/m2 respectively. The results show that the proposed model can be adopted for better performance. A thermo-economic analysis of an optimized output is conducted to conclude on capital investment and operation cost for sustainable power production. The analysis yields highest cost rate of exergy destruction of 58936.41$/year for the boiler. The investment cost of the turbines together is 89% of the total capital investment, and hence, thermo-economic factor is highest for these components.