A performance-based method for energy efficiency improvement of buildings

Building energy standards provide control over excessive use of energy in buildings, promoting energy efficiency and mitigating detrimental environment impacts brought by high energy consumption. The central objective of this paper is to develop correlations that will predict building heat gains and cooling energy consumption for commercial buildings in tropical climates. The energy performance index OTTV was first revised to obtain a new performance index, ETTV for commercial buildings. We developed new correlations to investigate the impact ventilation rates and building aspect ratios had on building cooling energy consumption. Comparing estimated and simulated results, we demonstrated good agreement, even for buildings having different aspect ratios. A study was further conducted to investigate the impact of weather conditions on the developed methodology for estimating the energy consumption of buildings. We employed a design-day weather file to provide simplicity, flexibility and greater ease of use. The design day concept is pivotal in providing key inputs to the cooling energy-estimating methodology yielding good agreement with DOE-2.1E simulated results. We believe that the results presented in this study will benefit building authorities in their pursuit of developing and refining stringent building energy standards in order to realize better energy efficient buildings.

Research highlights
► New building energy-estimating equation that accounts for varying outdoor air rate.
► New correlation compares building energy consumption operating with either VAV or CAV systems.
► New energy-estimating equation estimates well the cooling energy consumption in buildings of varying aspect ratio and orientation.
► Concept of a design-day weather file predicts well the cooling energy consumption.