The increase in urbanization leads to an intensification of the heat island effect, due to several factors:reduction in green areas; high solar absorptance of construction materials; waterproof surfaces; low skyview factors and natural ventilation effectiveness. Urban heat island characteristics have vast impacts andimplications on energy efficiency, environment, and at last on human comfort and health. The develop-ment of urban fabric involves the modification of the thermal fluid-dynamic field of the whole area aroundthe new buildings. This factor leads to worse the energy performances of all the structures affected bythe phenomenon. The study investigates on the impact of a new building complex as result of a redevel-opment process on the thermal and energy performances of the actual surrounding urbanized area sitedin Rome. The purpose is to provide results to better understand the urban heat island effects on climateinside cities and population health. The assessment was carried out through a monitoring campaign andnumerical analyses. The temperature field and the Universal Thermal Climate Index (UTCI) were calcu-lated for the current scenario of the area, for the redeveloped configuration and for a proposed scenariocharacterized by the adoption of mitigation strategies against urban heat island countermeasures, suchas vegetation improvement and cool materials able to limit the surface temperature rise under solarradiation.The new redeveloped configuration of the area induces an increase in average air temperature upto 3.5◦C in the central part of the day and a worsening of the maximum UTCI index up to 2.7◦C. Thisis caused by the increase of the number of obstacle to the natural ventilation, the replacement of soiland spontaneous vegetation with low albedo materials. The application of cool materials and vegetationdetermines a temperature decrease up to 2◦C, while the maximum UTCI reduction is moderate, about1◦C.© 2016 Elsevier B.V. All rights reserved.1. IntroductionIn 2009 the world energy outlook highlighted that most of EUpopulation lives in cities [1]. The trend in new building designsare focused on the return of an investment without any eval-uation of the possible worsening of the localized thermo-fluiddynamic conditions in energy and comfort terms. As a matter offact, the buildings are obstacles to the natural ventilation inducingan increasing of hot air masses and polluting agents inside urbancanyons.Therefore, research on energy consumption and human healthin urban areas are needed in order to reduce warming phenom-ena caused by the increase of urban density and the decrease of∗Corresponding author.E-mail
Battista, G., Carnielo, E., DE LIETO VOLLARO, R. (2016). Thermal impact of a redeveloped area on localized urbanmicroclimate: A case study in Rome. ENERGY AND BUILDINGS, Volume 133, 446-454 [10.1016/j.enbuild.2016.10.004].
Thermal impact of a redeveloped area on localized urbanmicroclimate: A case study in Rome
BATTISTA, GABRIELE;CARNIELO, EMILIANO;DE LIETO VOLLARO, ROBERTO
2016-01-01
Abstract
The increase in urbanization leads to an intensification of the heat island effect, due to several factors:reduction in green areas; high solar absorptance of construction materials; waterproof surfaces; low skyview factors and natural ventilation effectiveness. Urban heat island characteristics have vast impacts andimplications on energy efficiency, environment, and at last on human comfort and health. The develop-ment of urban fabric involves the modification of the thermal fluid-dynamic field of the whole area aroundthe new buildings. This factor leads to worse the energy performances of all the structures affected bythe phenomenon. The study investigates on the impact of a new building complex as result of a redevel-opment process on the thermal and energy performances of the actual surrounding urbanized area sitedin Rome. The purpose is to provide results to better understand the urban heat island effects on climateinside cities and population health. The assessment was carried out through a monitoring campaign andnumerical analyses. The temperature field and the Universal Thermal Climate Index (UTCI) were calcu-lated for the current scenario of the area, for the redeveloped configuration and for a proposed scenariocharacterized by the adoption of mitigation strategies against urban heat island countermeasures, suchas vegetation improvement and cool materials able to limit the surface temperature rise under solarradiation.The new redeveloped configuration of the area induces an increase in average air temperature upto 3.5◦C in the central part of the day and a worsening of the maximum UTCI index up to 2.7◦C. Thisis caused by the increase of the number of obstacle to the natural ventilation, the replacement of soiland spontaneous vegetation with low albedo materials. The application of cool materials and vegetationdetermines a temperature decrease up to 2◦C, while the maximum UTCI reduction is moderate, about1◦C.© 2016 Elsevier B.V. All rights reserved.1. IntroductionIn 2009 the world energy outlook highlighted that most of EUpopulation lives in cities [1]. The trend in new building designsare focused on the return of an investment without any eval-uation of the possible worsening of the localized thermo-fluiddynamic conditions in energy and comfort terms. As a matter offact, the buildings are obstacles to the natural ventilation inducingan increasing of hot air masses and polluting agents inside urbancanyons.Therefore, research on energy consumption and human healthin urban areas are needed in order to reduce warming phenom-ena caused by the increase of urban density and the decrease of∗Corresponding author.E-mailI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
