# A Methodology to Improve Energy Efficiency and Sustainability in Urban Environments
## 3 Microclimatic Analysis  
After the surveying phase of the current conditions of urban surfaces and climate conditions, some large-scale microclimatic analyses were conducted to examine how different existing materials may affect surface and air temperatures, as well as perceived human thermal comfort [20; 21]. For this purpose, a numerical model was built using ENVI-met software [22], which allows for the simulation of various microclimatic scenarios. The software was chosen because it is based specifically on the calculation of both thermodynamic processes occurring at the ground surface, roofs, and walls of buildings, and fluid dynamic characteristics, including airflow and turbulence, allowing the simulation of the wind flow around structures and the determination of complex micro-scale thermal interactions within urban environments [23; 24; 25; 26]. The microclimatic conditions were analyzed for July 24 th, representing a typical hot condition in Padova. Figure 4: Case study identification of the paved surfaces. The procedure of the model creation, analyzed with ENVI-met, started from an.osm file of the target area. This specific file, directly exported from OpenStreetMap [27], permits the creation of a 3D model based on spatial data, using mainly Grasshopper integrated with the Urbano tool. This initial file expedited the creation of a detailed model, where the building heights were adjusted, and the green and paved surfaces were subdivided according to the different typologies. Through the components of Dragonfly tool, it was then possible to assign appropriate materials from the ENVI-met library to all surfaces and volumes, which could be modified as needed. Dragonfly, in fact, permits the connection between the two different work environments, Grasshopper and ENVI-met. At this stage, the model was connected to an.epw file [28], which represents a kind of database in which all the climatic information, measured by satellite sensing stations, is recorded for each station in the world. This file also includes georeferencing data for the model. This is a file that can be downloaded online from several collections by selecting the necessary reference station, and in the case described, the collection provided directly by Ladybug was used. After connecting the 3D model with the climate information belonging to the actual location of the area, the exportation of a readable model for the simulation environment resulted in two files. The first one contains the purely geometric and physical information of the model, in.INX format, and a second file contains all the climatic and environmental information selected for the analysis (Figure 5). These two files were of fundamental importance for the subsequent simulations conducted using the ENVI-met software. In the first image (Figure 5a), the model is read in the Space section, and in the picture beside it (Figure 5b), the data are read in the ENVI-guide section of the software. Using the ENVI-core section represents the following step. This, in fact, permits the integration of the two previous parts described, analyzing each voxel of the model together with the integrated information. The key findings from the simulations are summarized as follows. Two simulation scenarios were performed: the first corresponded to the actual situation in the area (AS), whereas the second involved the replacement of pavements to mitigate their thermal response to the local climatic conditions (CPS). The first scenario highlighted the impact of pavements on generating the urban heat island effect, allowing the visualization of peaks in surface and air temperatures reached especially during the hottest hours of summer days. This permitted the identification of the areas where pavement replacement interventions would be most beneficial. After these analyses were related to the actual state of the area, the replacement of these pavements with cool materials was considered.