Evaluating the applicability of Typical Meteorological Year under different building designs and climate conditions

Abstract

Typical year weather files are synthetic files generated from historical weather data used in building energy simulation to evaluate energy performance of buildings. The current work is to illustrate the impact of building types and designs on the deviations between the energy demand predicted using typical year weather files and the average energy demand predicted using 30-year long-term actual year weather data. This study explores design parameters, which have great impact on energy demands, including window-to-wall ratio, window solar heat gain coefficient, floor construction, and solar reflectance of exterior walls and roof. These design parameters are applied to two different building types — small and large office buildings, and two different climatic locations — Montreal and Vancouver, Canada. The results indicate that certain designs exhibit wider deviations between energy demands predicted with a typical year and the long-term average. The maximum deviation is found to be around 4.5%, which suggests that typical year weather file is still a reliable means to predict the long-term average cooling and heating energy performance. However, the study also found that typical year weather files underestimate the peak load in the long run for up to 85% of the time.