Cooling effect of evaporative misters in outdoor restaurant areas: case study of Novi Sad, Serbia

Continuing urbanization, together with climate change manifestations, including the increasing frequency and intensity of heat waves, prompts the adoption of various cooling interventions in urban outdoor spaces. Evaporative misting systems have gained popularity as a cost-effective heat mitigation measure, particularly in hospitality venues. However, their effectiveness in moderate climates remains understudied. This study evaluated the effectiveness of these systems in restaurant outdoor seating areas in Novi Sad, Serbia, during hot summer days in 2022 and 2023. Simultaneous micrometeorological measurements were conducted at multiple locations in restaurant outdoor seating areas (sun-exposed, shaded, misted, and non-misted sites), with mean radiant temperature (MRT), Physiological Equivalent Temperature (PET), and Universal Thermal Climate Index (UTCI) being calculated. Additionally, to capture subjective perceptions of microclimatic conditions, questionnaire surveys were conducted with restaurant guests. Results revealed significant location-specific variability in cooling effectiveness. The most favorable thermal conditions occurred in shade; however, in sun-exposed locations, misting systems showed inconsistent performance, sometimes even worsening thermal conditions. Despite these inconsistencies, questionnaire results showed that guests consistently perceived improved thermal comfort under misting systems. Further research should include measurements across different times of day and seasons in moderate climates and across different misting types and intervals to better understand misting systems' cooling benefits.