Assessing the Interaction Between Urban Heat Island Effects and Optimal Passive Design Strategies for Residential Buildings Across Moroccan Climatic Zones

This study investigates the impact of the Urban Heat Island (UHI) effect on building energy performance and the optimization of passive design strategies in six Moroccan climate zones: Agadir, Tangier, Fez, Ifrane, Marrakech, and Errachidia. A computer simulation approach combined with multi-objective optimization using the NSGA-II algorithm was employed to improve energy efficiency while maintaining thermal comfort for a single-family house. The optimum solutions include several passive design parameters, such as insulation materials and thickness, glazing types, window-to-wall ratio (WWR), ventilation rates, shading devices, building orientation, and heating and cooling set point temperatures. The analysis was studied under both standard climate data and UHI scenarios to evaluate the impact of increased urban temperatures on building performance. The results show that under standard climate conditions, the optimal design can achieve up to 76% energy savings throughout all the climate zones, while Marrakech can save 67% and Errachidia 64%; however, under UHI scenarios, these energy savings dropped by 8–30% depending on the climate zone. For example, Agadir drops from 76% to 49% under a 5°C UHI scenario, and Marrakech drops from 67% to 56% under a 3.5 °C UHI scenario, highlighting the significant impact of urban overheating on buildings. These findings emphasize that integrating the UHI effect is essential for accurately assessing passive design performance and for ensuring that selected design solutions truly minimize energy consumption under realistic urban conditions, while also underscoring the importance of integrating passive design strategies into residential buildings. These strategies promote sustainable building practices in Morocco by reducing energy consumption and improving occupant thermal comfort.