A novel combined Kalina and ejector booster power/cooling cycle: Energy and Exergy analysis

This study presents a novel integrated thermodynamic cycle that combines the Kalina cycle with an ejector booster refrigeration cycle (EBRC) to simultaneously produce power and cooling from low-grade heat sources. The proposed configuration uniquely employs the mechanical power generated by the Kalina turbine to directly drive the compressor unit of the EBRC, thereby significantly reducing the reliance on external electrical grid input and enhancing the cycle's overall efficiency and self-sustainability. By recovering and redirecting waste thermal energy within a coupled architecture, the system offers a dual-generation solution particularly suited for industrial and renewable energy applications where energy quality and source availability are limited. A detailed thermodynamic model is developed and validated to perform energy and exergy analyses under various operating conditions. The impacts of critical parameters, including turbine inlet temperature and pressure, basic ammonia concentration in the working fluid, evaporator and condenser temperatures, are thoroughly investigated to determine their effects on performance metrics such as net power output, cooling capacity, coefficient of performance (COP), and exergy efficiency. Furthermore, a single-objective thermodynamic optimization executed via the Genetic Algorithm revealed that the integrated cycle achieves a peak COP of 0.3318 and a maximum exergy efficiency of 50.64% under the mathematically converged optimum operating conditions. The study demonstrates that this original configuration offers a promising and technically viable pathway for maximizing low-grade heat recovery in compact, high-efficiency power-cooling cogeneration applications.