Estudo de um indicador de eficiência energética integrado para análise do desempenho de condicionadores de ar de baixa capacidade

Abstract

The following study approaches the influence of climatic conditions, usage profile in different environments and the use of the inverter technology on Split Hi Wall models, applied in residences and small size businesses in Brazil, by using an integrated energy efficiency indicator. Considering that this is the most used model in those types of environment, there is great potential for reduction of energy consumption if professionals who work in the field and consumers have guidance in choosing equipment that is proven to be more efficient. The study presents the methodology developed for: selecting cities that will portray different bioclimatic zones in Brazil; defining the construction and usage features of a living room and an office; determining the coefficient that represents the performance curves of an operating Split Hi Wall device, with capacity of 2640 W and Coefficient of Energy Efficiency (CEE) of 3.30 W/W. By using the computer software EnergyPlus, the performance of the device with fixed and variable speeds was simulated 24 times in living rooms and offices in the cities of Curitiba/PR, São Paulo/SP, Brasília/DF, Campo Grande/MS, Cuiabá/MT and Fortaleza/CE, during one year of operation. Utilizing an integrated indicator, the Integrated Energy Efficiency Ratio (IEEC), and analyzing the results of one year’s operation, the studied model achieved 4.95 W/W, 50% above the nominal CEE (3.30 W/W), given that the devices with the inverter technology reached values that are 29% above the fixed speed ones. Regardless the technology, the analyzed models show the highest rates of IEEC in outside temperatures that range between 20°C and 25°C, being 4.01 W/W on the fixed speed models and 5.18 W/W on the inverter ones. The Part Load Ration (PLR) that ranges between 0.4 and 0.6 shows the highest amount of maximum rates, being able to reach a 5.19 W/W rate with the inverter. The acquired information served as a foundation for the creation of a proposal to calculate an integrated energy efficiency coefficient, which uses information from climate archives and EEC results according to the load factor and outside temperature, without the need of simulation softwares, being able to provide the necessary subsidies for the correct selection of the most efficient air conditioners.