ASHRAE Standard 205P recently concluded its ?rst ad-visory public review. The standard, entitled “Stan- dard Representation of Performance Simulation Data for HVAC&R and Other Facility Equipment”, makes the ?rst attempt to standardize the way performance data is con- veyed between HVAC equipment manufacturers and en- ergy modelers. The standard de?nes speci?c data ele- ments that represent the complete performance of equip- ment for use in building performance simulation tools.In parallel with the public review, an initial implementa- tion of the standard was prototyped using Google’s Flat- Buffer data serialization format. FlatBuffers provides a very computationally and memory ef?cient format that is also compatible with the more common JSON format. FlatBuffers generates minimal software source code in several languages including C/C++, Python, Java, and JavaScript based on a single schema describing the data elements.A prototype implementation demonstrates the process of generating an ASHRAE Standard 205P liquid-cooled chiller data ?le from a manufacturer’s spreadsheet using Python, and subsequently reading that same ?le into a C++ program. This process demonstrates the versatility of the new standardized data format. Any participating manufacturer can use a similar process to provide equip- ment performance to a user that will represent a speci?cmodel in any participating simulation software tool.