Performance analyses of basic cogeneration basic cogeneration plants in agriculture and food production

Abstract

Energy in agriculture and in food production have vital importance that affect directly the cost and the quality of the products. Micro cogeneration plants are widely used in the World to produce heat and electricity at the same time in a same plant. The aim of this study, to analyze the performance of the production of power and heat for the food production process and the agricultural needs. For that reason, a basic cogeneration plant is taken to analyze the performance by using 1st and 2nd laws of thermodynamics and exergy analysis method. The electric-heat exergy rates, the energy and exergy efficiencies, the combustion chamber and the gas turbine outlet temperatures, the total electric and heat energies and exergies, and the specific works were calculated for various ambient temperatures and for various excess air rates of the basic cogeneration plants fueled with methane. The effects of the various ambient temperatures and the various excess air rates on the performance of the basic cogeneration plants were obtained, discussed and analyzed. For the best performance and for the best working conditions of the basic cogeneration plants in agriculture and food production process and food industry recommendations were done. It was found that, lower ambient temperatures give higher electric efficiency, but lower heat efficiency. However, an optimum excess air rates for the best performance was found at the value 2.3 of the excess air rates of the basic cogeneration plants fueled with methane.