Análise termoeconômica e de emissões de gases de efeito estufa do sistema de água gelada de um shopping center

Abstract

The growing awareness about the need to reduce the environmental impact of energy systems motivates searches for more efficient and eco-friendlier equipment. In this context, Thermoeconomics plays a vital role, as it makes it possible to investigate how energy and resources degrade and to minimize the energy consumption of thermal systems. This discipline has been combined with the Life Cycle Assessment (LCA) to provide crucial information on the environmental impacts in productive systems. In this way, this work applies a combination of the UFS and H&S methods and the LCA for the thermoeconomic and greenhouse gases emissions analyses of a chilled water system in a shopping mall. Initially, the object of study was described. Then, a thermodynamic analysis was performed to assess the system's behavior and validate the collected data. The thermoeconomic analysis started with the determination of internal flows, definition of inputs and products and description of the productive structure. Then, the exergetic and monetary costs were determined. It was also possible to obtain the environmental costs. For that, it was necessary to determine the emissions over the life cycle of the components, through an LCA. Consistency was verified in the thermoeconomic analysis since its results are in accordance with the Second Law of Thermodynamics. The heat exchangers showed efficient thermoeconomic behavior. And then, there was a total monetary cost of R$ 1.2595, and environmental cost of 0. 8186 kg CO2-eq, for each MJ of thermal energy taken from the water that is stored. It is important to emphasize that besides providing results from an engineering perspective, this work had the contribution of disseminating the application of alternative thermoeconomic approaches in refrigeration systems.