Numerical analysis of radiative cooling behavior: Advancing the study of materials’ potential for urban overheating mitigation

The rapid increase in population, energy-saving demands, the need for indoor–outdoor thermal comfort, combined with rising global temperatures, highlight the urgency for efficient cooling strategies in the built environment. This study investigates aluminum- (“A”)and Vikuiti- (“V”)based materials for passive radiative cooling (RC), designed with tailored thermo-optical properties compared to a pure aluminum sample (“ref”). After the experimental characterization of the samples, a Finite Element Method (FEM) model is developed and validated to simulate the RC performance under typical mid-latitude summer and winter conditions. This approach enables accurate prediction of seasonal behavior, reducing experimental effort and resource consumption. Results confirm the model’s capability to reproduce the RC phenomenon, particularly the radiative exchange within key spectral wavebands. Among the tested materials, the “V” sample achieves a sub-ambient cooling of −9.7 °C under summer conditions with minimal convective influence, emphasizing the critical role of spectral selectivity in material design for real-world applications. Furthermore, a parametric analysis investigates RC potential under hypothetical spectral configurations and varying atmospheric transmittance, extending the model’s applicability and offering insights for optimizing passive cooling solutions.