Test and Validation of Building Energy Simulation Tools

Abstract

Building Energy Simulation Tools (BESTs) are essential for the evaluation of building design schemes for new building, and for ascertaining the impact of new technologies on energy performance of building. However, the discrepancy between predictions by different BESTs can be significant (Judkoff, et al, (1980)). Several communities including the International Energy Agency (IEA), have conducted tests and validations involving many BESTs; and many processes have been invented, which cover analytical approaches, comparative and empirical tests and validations. However, till now, no study has been reported for the tropical climatic conditions. Software users in this region rely only on the test and validation results of other regions. This thesis aims to bridge this gap through a comprehensive test and validation study, including comparative study, empirical validations and sensitivity analysis. Three popular software packages, namely TAS 9.0.9, IES 5.9.0.1 and EnergyPlus 2.2.0 were chosen for this study. It is found that 1) the state of art BESTs have potential accuracy issues, like solar radiation and long-wave radiation algorithms in TAS; 2) compensation between different heat transfer mechanisms will reduce the total discrepancy in predicted annual cooling load; 3) when comparing prediction with real measurement, infiltration and internal thermal mass will affect a lot; however by a careful estimation of these two factors, prediction can match measurement well; 4) the chosen BESTs are most sensitive to outdoor air temperature, construction properties than other meteorologic, dimensional, and other energy simulation-related parameters.