Parametric analysis and optimization of a Kalina cycle driven by solar energy

A solar-driven Kalina cycle is examined to utilize solar energy effectively due to using ammonia–water's varied temperature vaporizing characteristic. In order to ensure a continuous and stable operation for the system, a thermal storage system is introduced to store the collected solar energy and provide stable power when solar radiation is insufficient. A mathematical model is developed to simulate the solar-driven Kalina cycle under steady-state conditions, and a modified system efficiency is defined to evaluate the system performance over a period of time. A parametric analysis is conducted to examine the effects of some key thermodynamic parameters on the system performance. The solar-driven Kalina cycle is also optimized with the modified system efficiency as an objective function by means of genetic algorithm under the given conditions. Results indicate that there exists an optimal turbine inlet pressure under given conditions to maximize the net power output and the modified system efficiency. The net power output and the modified system efficiency are less sensitive to a change in the turbine inlet temperature. An optimal basic solution ammonia fraction can be identified that yields maximum net power output and modified system efficiency. The optimized modified system efficiency is 8.54% under the given conditions.

► A thermal storage system is introduced to provide stable power output.
► A modified system efficiency is defined to evaluate the system performance.
► The effects of thermodynamic parameters on the performance are examined.
► Parametric optimization is conducted to find the optimum performance by GA.