Urban energy–microclimate digital twin: Census-tract validation using mobile traverses and utility billing benchmarking

¹ School of Geographical Sciences and Urban Planning, Arizona State University, Tempe, AZ, USA
² School of Architecture, Mississippi State University, Mississippi State, MS, USA
³ Data Science Academic Institute, Mississippi State University, Mississippi State, MS, USA
⁴ KAUST Climate and Livability Initiative, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia

^* Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Abstract

Urban Building Energy Modeling tools increasingly couple building loads with urban microclimate, yet empirical validation in hot-arid cities remains limited. We evaluate the CityDigitalTwin (CDT) platform in a neighborhood near Arizona State University's Polytechnic Campus (Mesa, AZ) during a hot July 2025 period. CDT couples a GPU-accelerated fast-fluid-dynamics microclimate solver with an archetype-based urban building energy model, driven by boundary conditions from the nearest upwind airport weather station. Mobile vehicle traverses provide 2-m air-temperature observations for model evaluation on 19 July; neighborhood-mean absolute differences across four districts range from 0.09 to 1.30 °C (mean 0.63 °C). Electricity use for 15 single-story residential buildings is simulated using DOE/ESS-DIVE archetypes and a Min-Max Archetype Sweep over eight uncertain parameters; 87% of measured daily loads fall within the model interquartile envelope and all values lie within the simulated min-max bounds. Results indicate that CDT can reproduce both outdoor thermal patterns and cooling-dominated electricity use with accuracy suitable for neighborhood-scale planning and heat-mitigation studies.