Adaptive “Velari”

As it is known, the global phenomenon of rising temperatures causes uncomfortable and often harmful conditions for human beings living in moderate-climate zones, such as the Mediterranean area, especially in the hottest periods. Examinations of metropolitan cities can witness that high temperatures generate Urban Heat Island (UHI), due to population, buildings, vehicles and human activi-ties in general. With the increase of rising temperatures in the latest decades, people living in big cities have gotten used to tackling heat discomfort with electricity charged cooling systems. As a result, the energy consumption for air-conditioning causes UHIs’ effects to further grow. It is scientifically confirmed that the behavioral habit of relying on artificially generated cold whenever temperatures rise will even-tually make the climate crisis more problematic in the near future. Energy commu-nities are used to producing, storing and consuming energy on site; therefore, power sources must be in close proximity to users. Albeit neglected in the Modern Era, the most proximate and sustainable energy supply is directly available to us: sunlight. The origin of hot temperatures, discomfort and energy waste is, indeed, the most exploitable power generator men can access to. In Southern Europe or Middle East cities, the use of veils as urban-scale shading devices is part of the consolidated tradition; a well-known example can be found in the Spanish city of Sevilla, where textile curtains named “Sevillans” are stretched between buildings. At the present time, we’re witnessing that the climate mitigation action of shading systems can be pursued in combination with energy production, with the development of membrane integrated flexible photovoltaic cells (PV). Masdar City in the United Arab Emirates, designed by the Foster Studio, or the Solar trees of the German pavilion at EXPO 2015 in Milan and the Promenade of the EXPO 2021 in Dubai are some innova-tive yet relevant cases. The use of PV cells for sun-shielding purposes is optimal to respond to a double-sided problem with a single object. Manufacturing an adaptive velario using composite fibers (i-Mesh), could both allow us to design the shape and modulate the density of integrated PV cells as needed. Method: To identify the best position for the adaptive tensile canopies, it is necessary to superimpose different site-specific data: temperatures in the urban area, in particular close to buildings; surfaces that receive most of the daytime radiation; sunlight and ventilation. To develop the most suitable solutions to many environmental scenarios, three-dimensional simu-lations performed with virtual models must be used both at urban (Envimet) and at building scale (in-Sight). Expected results: An algorithm capable of determining the “Velari” best position and the proper shading/density factor. A model, applied to a case study in Rome, to serve an evaluation of the benefits of this technology in terms of decreasing surface temperatures of external horizontal and vertical surfaces of buildings and streets.