A New BIM to BEM Framework: The Development and Verfication of an Open-Source gbXML to EnergyPlus Translator for Supporting Building Life Cycle Performance Analysis

gbXML is an open schema that supports data inter-operability between BIM applications and different building design software tools (gbXML, 2018). Its capability to bring in geometric and construction information can help reduce the time and uncertainty of the energy modeling process (Ham and GolparvarFard, 2015). However, during the design cycle, when both geometric and system data are updated continuously, the lack of methods to quickly insert system information in the BIM-exported gbXML has a significant impact on the modeling efficiency as well as the model integrity. This project aims to develop an open-source gbXML to EnergyPlus translator, the gbEplus, which provides flexibility for user-defined system modules plug-in. It adopts the OpenStudio reverse translator to ensure a quality geometry and construction data conversion. A plug-in interface is designed as the gateway for importing data from external resources to gbXML-EnergyPlus translation process in the run-time, and all the previously developed system modules can be stored in a userdefined library for reuse in the future. The gbEplus was developed and validated with models from Phase II gbXML geometry benchmark test documents. Two applications, for parametric design and model calibration, were developed to demonstrate the adaptability of this new BIM-BEM tool.