How Accurate is Energy Modeling in the Market

Abstract

NBI has recently completed a study of whole building energy use of over 120 completed LEED buildings nationwide. This paper presents an analysis of a subset of this research, focusing on the use of energy modeling as a predictor of building performance for this building sample. As part of this analysis, NBI reviewed modeling results for approximately 90 buildings that used the ASHRAE 90.1 Standard as a modeling baseline, and predicted building energy savings compared to this standard 1 . An analysis of the baseline, predicted, and actual energy use for these buildings yields a fascinating set of data with significant implications on the use of this standard as a predictive tool and code baseline. The results of the analysis also impact ongoing national discussions about how the design industry can respond to the Architecture2030 challenge and other carbon reduction goals. The data set has been analyzed in the context of building size, type, and climate, and the results suggest the need for modifications to energy code and regional load projection policy considerations, building life cycle cost analysis, and the practice of energy modeling. Areas of significant additional research topics are also indicated. The goal of this session is to present the results of this study, and to solicit an informed discussion of the far-reaching implications of the data.