Building Performance Simulation for Architects, Comparing Three Leading Simulation Tools

The primary objective of this research was to assess, compare, and contrast the capabilities of the most commonly used BEM tools by architects: Designbuilder, eQuest, and IES-VE, concerning their effectiveness in modeling a complex academic building and simulating its energy use. The research defined a set of evaluation criteria based on previous studies from the literature review as follows: 1) Usability, 2) Data Interoperability, 3) Support Options, 4) Information Management, and 5) Computing Capabilities. The objective of the criteria was to assess the suitability of these tools to be used by architects during preliminary design phases, and identifying any additional development that may be needed for these tools to achieve the required penetration in this critical sector. The results of the research showed strength in eQuest in importing thermal and construction data from the gbXML file, which both Designbuilder and IES-VE were not able to successfully do. On the other hand, IES-VE and Designbuilder were more successful in importing the geometry data, which encountered many issues by eQuest. IES-VE and Designbuilder provided a variety of support options while eQuest had insufficient support resources. On the other hand, eQuest was the fastest simulation running tool, and due to the successful thermal and construction data interoperability, least data input was required by architects; however, the GUI on eQuest was not as friendly as IES-VE and Designbuilder. Although IES-VE and Designbuilder required higher efforts especially on thermal, and construction data input, their comprehensive template library compensated part of the effort needed for data reentry. Finally, load and energy simulations were carried with only one variable "template default values of VAV HVAC system" resulted in 10%, and 28% higher equipment and lighting energy used respectively on Designbuilder when compared to IES-VE and eQuest. On the other hand, the heating to cooling ratio was higher on eQuest (2:3) compared to that of IES-VE and Designbuilder (1:3). To conclude, the results showed that eQuest could offer more potential for construction and thermal data interoperability with significantly faster simulation time, while IES-VE and Designbuilder can provide more potential with their built-in comprehensive templates data library as well as architect-friendly GUI and presentation of output results.