Notes paper: enabling building application development with simulated digital twins.

Despite the promise of "digital twins", prototyping building applications remains difficult due to the diverse structure and composition of building control systems and lack of standard descriptions and representative test buildings. Recent advances in building simulation software allow development of control sequences in a realistic and reproducible manner, but lack industry-standard interfaces and thus impede porting developed controls to real buildings. In this paper, we discuss the design and implementation of a simulated digital twin which uses open-source technologies to present simulated buildings as if they were "brick and mortar." We demonstrate how integrating building simulations software, control network virtualization and semantic metadata into a digital twin facilitates application prototyping and enables future novel applications.