Cross-Platform Application for High Resolution Thermal Comfort Mapping from Energy Models

Many building design professionals assume that, as long as there is an heating/cooling system that is sized to meet a thermostat temperature at the center of the room, occupants throughout the space will be comfortable but this assumption is far from reality. Within a given space that is exposed to an exterior facade, temperatures can vary widely, increasing the risk of occupant discomfort. This is an issue in its own right but perhaps the larger missed opportunity is that many of the strategies that would mitigate such conditions such as shading, better-insulated windows, and lower glazing ratios, would also save heating and cooling energy. While contemporary standards include models to help account for variation thermal in conditions across a space, many of these models are new and there is still a large gap between a strategy implemented on a building and the inputs to these models. This SBIR proposal seeks to close this gap by developing a cross-platform, open source application for indoor thermal comfort mapping at both a high spatial and temporal resolution. The application will accept energy models in various file formats and will leverage the BTO-funded tools EnergyPlus/OpenStudio and Radiance engines towards this end. It will allow for ease of input from several graphical interfaces, including CAD software and third-party energy modeling software, and it will enable the adoption of new spatial thermal comfort metrics into standards. Phase I will involve the development of platform-agnostic core software libraries to support comfort mapping capabilities. This includes libraries for preparing energy models as well as as libraries for computing spatial thermal conditions from energy model results. Ultimately, the libraries will be packaged with the calculation engines into an application that can be called via command line by individuals or third party applications. Lastly, the libraries will be used to add thermal comfort mapping capabilities to plugins for widely-used CAD interfaces. The development done in Phase I will allow users to visually communicate the difference in spatial thermal comfort between different facade and heating/cooling system strategies. At the same time, it will grant a means of assessing the comfort benefits of strategies in completely passive buildings, which currently face hurdles to utilizing energy model technology given that there is no energy use to compare between options. During Phase II, the cross-platform compatibility of the application will enable the setup of cloud computing services, allowing users to run much larger thermal comfort studies and receive results within reasonable time frames.