Optimizing Urban Layout for Solar Mitigation and Microclimate Regulation in Hot-Arid Coastal Resorts: A Parametric Simulation Study

Abstract

The rapid expansion of tourism infrastructure in hot-arid coastal regions exacerbates energy demands and environmental stress, yet evidence-based urban design guidelines for low-density resorts remain underdeveloped. This study investigates the influence of urban layout design (ULD) on façade solar exposure and microclimate regulation, using Egypt's Red Sea coast as a case study. Its purpose is to identify morphological strategies that reduce solar heat gain, lower cooling energy demand, and enhance outdoor thermal comfort while facilitating renewable energy integration. A systematic parametric approach was employed, using TownScope-3 to generate and simulate 252 urban layout scenarios. Key urban form parameters—including open-space ratios, building orientation, canyon aspect ratios, and building distribution—were varied to evaluate their effects on façade-level solar radiation. Statistical analyses established robust correlations between morphology and solar mitigation outcomes. Findings demonstrate that urban morphology is a decisive determinant of environmental performance. East-West linear layouts reduced annual façade solar irradiation by up to 29%, while compact, vegetated U-shaped clusters achieved reductions of up to 48%. Based on established correlations reported in the literature, these solar reductions correspond to estimated cooling energy savings of 23–32% and significant improvements in outdoor thermal comfort. Furthermore, by lowering ambient thermal loads, these passive strategies enhance the operational efficiency and feasibility of photovoltaic (PV) systems, positioning urban layout as a dual passive-active sustainability lever.