Evaluation of ANSI/ASHRAE/USGBC/IES Standard 189.1-2009

The National Renewable Energy Laboratory (NREL) evaluated ANSI/ASHRAE/USGBC/IES Standard 189.1-2009, 'The Standard for High-Performance Green Buildings Except Low-Rise Residential Buildings'. NREL performed this evaluation by examining the results of predictions for site energy use from a comprehensive set of EnergyPlus models. NREL has conducted an 'order-of-magnitude' analysis in this study to identify the likely overall impact of adopting Standard 189.1-2009 over ANSI/ASHRAE/IESNA Standard 90.1-2007.