Análise do desempenho termoenergético do prédio administrativo da Universidade Federal do Pampa, campus Alegrete

Abstract

The present work has the objective of analyzing the thermoenergetic performance of the administrative building of the Federal University of Pampa, located in Alegrete city – Rio Grande do Sul State, by proposing improvements in the building envelope and air conditioning system, with views to reduce the building energy consumption and maintain the thermal comfort of the occupants within the acceptable levels. The software used for the simulations was Energyplus version 8.7 and they were based on 14 design days conditions to size the air conditioning system and on city weather data to calculate the building energy consumption. The building under analysis was arranged into 66 thermal zones, in which 39 zones have air conditioned equipments installed (packaged terminal air to air heat pump), popular splits. Firstly, the simulations were performed to obtain the cooling and heating capacities for each thermal zone by applying the Ideal Loads Air System mode, whose results were compared with air conditioning capacities currently installed. The simulations showed that 38 zones are oversized 42% and 41% on average above the nominal cooling and heating capacities respectively. By analyzing the campus library, which has an external surface area of nearly 50% in window glasses, the simulation of the replacement of the current single window glazing by the insulated window glazing, resulted in a reduction of 13% and 18% on average of cooling and heating capacities respectively. The VRF (Variable Refrigerant Flow) air conditioning system simulation showed an annual electricity energy consumption reduction of approximately 18,6% in relation to all building energy consumption, and 55,2% reduction compared to the current air conditioning system. The campus library PMV results are +0.92 and +0.82 with the single and insulated window glazing respectively. This last one result was strongly influenced by the mean radiant temperature reduction, but it is still above the PMV interval recommendation (-0.5/+0.5) for the thermal comfort.