Impact of building types and CHP plants on air quality (2019-2021) in central-eastern European monocentric agglomeration

The quality of city air is influenced by many factors, including the density of buildings, the roughness of the terrain, the presence of street canyons, the heat sources in buildings, the types of industry, the topography, and meteorological conditions. Official air quality monitoring systems measure a very limited number of points, making local analysis im-possible without the use of mathematical modeling programs. Here, we present an analysis of local air quality in an urban agglomeration. Data were collected over three years (2019, 2020, 2021), using commercial sensors located throughout the area of investigation. Dense downtown buildings equipped with individual heat sources were not found to have any impact on local air quality. The local municipal combined heat and power (CHP) plants contributed <1 parts per thousand of the measured concentration of particulate matter. Land height and the density of single-family housing were found to significantly affect air quality. We also took into account the influence of weather conditions, wind speed, and wind direction on the concentrations of particulate matter. High concentrations of particulate matter occurred only during heating periods when wind speeds were moderate. Wind direction did not have a direct impact on air quality, despite the expected benefits of ventilation through air corridors.