Bioclimatic simulation, environmental based urban design and architectural redevelopment in the Mediterranean Area: a didactic approach for the training of future professionals

The study presents a synthesis of the didactic experience called "Bioclimatic simulation, environmental based urban design and architectural redevelopment in the Mediterranean Area", in which, among others, the case study of the Tor Fiscale district in Rome was addressed; the latter deals with the theme of the self-reliant city, of the heat island effect mitigation, and of the energy and environmental efficiency of buildings from passive energy efficiency and smart grid point of view. The learning process tested on students is based on the study and simulation of climate, urban and local microclimate factors, of the utmost importance for the training of future professionals with a strong environmental sensitivity, in addition to the traditional analysis of a typical urban fabric characterized by strong historical, archaeological and environmental features. The microclimate area simulation is used as a decision making support tool aimed at deepening the critical-knowledge on the area and the proper formulation of objectives and strategies through a process characterized by a flexible and adaptive approach with the aid of retroactive feedback. The study sets out the specific biophysical and bioclimatic features to consider when developing objectives and strategies of intervention in a portion of urban tissue. The case study of Tor Fiscale is analysed in its peculiar characteristics of an area substantially closer to the centre of Rome, characterized by a strong presence of archaeological and natural values, together with a context of strong environmental degradation and unauthorized building construction. The paper concludes with assessments developed within the framework of the didactic process, along with a report on the teaching experience for further didactic improvements and three design results directly related to the analysis and the didactic process. Framework definition and question remarks In Europe the energy consumption of the building sector accounts for about 40% of the overall demand for energy; buildings consume 40% of the incoming material into the economy and generate approximately 40-50% of the greenhouse gases produced (Ardente et al. 2011). Cities host now more than 50% of the world population (UN 2012) and although they take up less than 3% of the earth’s surface, they consume 75% of the total energy produced and produce 80% of all greenhouse gas emissions (Brown 2001) (European Commission 2010). The European Directive 2010/31 has already set ambitious targets for reducing energy consumption for the building industry and a central role for the achievement of these objectives will increasingly be carried out also by the evolution and development of the city not as a sum of individual buildings but as a system of interrelated energy flows as much as possible self-reliant, that is tending to prefer the local production of services, goods and energy according to the well-being of the community (Shuman 2000). A further articulation of this principle applied to energy requires the consideration of geography and natural resources both as a mean to meet the energy demands of the city (Grewal and Grewal 2013) and as a mean to transfer the principle of the energy efficiency of buildings to the energy efficiency of the urban fabric through its passive behaviour, as the latter is capable of significantly reducing energy consumption of the buildings within it at the source (Yang et al. 2012). The urban climate is strongly influenced by natural and anthropogenic factors dependent on the density and the heat storage capacity of the built fabric, the presence of mineralized or green surfaces and pollutant emissions. The heat balance of a city is very different from that of a suburban area and the phenomenon is called the “heat island” effect. The urban heat island is the best example of increased energy consumption of a city due to anthropogenic-induced changes in microclimate and local climate (Gartland 2008, Grimm et al. 2008). The triggering factors related to the effect of urban canyon, the decrease in convective exchanges data from the wind and pollution, are summarized in the table below (D’Olimpio 2008, RUROS 2004). Studies show that mitigation of the heat island can produce savings in energy consumption for summer cooling between 20 and 30% (de la Flor and Domı́nguez 2004, Akbari, Pomerantz, and Taha 2001).