Energy and Exergy Analysis of Modified Kalina Cycle for Cogeneration of Cooling, Heating and Power

Energy plays a significant role in the development of human societies, and scientists consider usage of energy resources as a factor in the development of countries. In general, energy sources can be divided into three groups: fossil, renewable and nuclear. Estimates show that due to the high consumption of fossil fuels in the last ۲۰۰ years, these resources can be the answer to energy for the next ۴۰-۶۰ years at most. Also, the use of fossil fuels causes the emission of a significant amount of polluting gases, including carbon dioxide, into the atmosphere, thus, using clean and renewable energy sources as a solution will lead to less emissions. In this article a cogeneration cycle for heat, power and cooling will be proposed and thermodynamically analyzed. The proposed cycle uses biomass as a renewable source of energy, the gasification cycle and the cogeneration cycles will be analyzed using energy and exergy analysis, then environmental impact of the cycle will be assessed using exergo-enviornmental methods. According to the obtained results, it can be seen that the efficiencies are optimized in a certain pressure ratio, which is ۳۲.۳۳% for the first law and ۲۶.۸۷% for the second law. The reason for this is that the work of the turbine increases up to a certain pressure ratio, but after the optimum pressure ratio, the increase in the input work of the compressor is more than the output work of the turbine. As the gas turbine inlet temperature increases, both the efficiency of the first law and the efficiency of the second law increase. For increasing the temperature of the system to ۴۰۰ degrees, the efficiency of the first law increases to ۹.۹% and the efficiency of the second law increases to ۶.۹%.

Keywords:

Renewable Energy , Biomass , Cogeneration , Gasification