Plug&Play: Self-Sufficient Technological Devices for Outdoor Spaces to Mitigate the UHI Effect

Abstract

Over the period since the foundation of the University “La Sapienza” of Rome to date, the progressive expansion of the urbanized areas to its surroundings has led to a strong acceleration of the soil sealing process, implemented with artificial materials such as asphalt or concrete used for the construction of buildings and settlement roads. The climate surveys show that around the city of studies in the last 50 years, the climate has become warmer due to the less vegetal transpiration and evaporation and the wider waterproof surfaces. In fact, despite the parts with vegetal covering and their evapotranspiration, the heat produced by the air conditioning in synergy with the city traffic and with the absorption of solar energy by dark surfaces in asphalt and concrete contributes to the local climate changes of La Sapienza, causing in summer the effect of “urban heat island” (UHI). The research project took as its starting point the current condition of the building heritage of the university campus by defining a framework of outdoor interventions aimed at transforming it into a resilient university city, able to protect its inhabitants—students and professors in charge of the work—the soil, and internal infrastructure from the risks of the UHI. The research provides a series of meta-design scenarios for the identification and development of strategies and outdoor solutions to be implemented with traditional materials such as vegetation and water and innovative ones such as cool materials for the regeneration of outdoor spaces while respecting cultural, educational, and historical values of the university campus. In addition to the definition of a meta-design framework, the research proposes a micro-architecture, self-sufficient from the energy point of view, able to contribute to the mitigation of the UHI phenomenon, thanks to the creation of a functional space serving the university community whose internal microclimate acts on Universal Thermal Comfort Index (UTCI) values.

The architectural device is characterized by a smart roof through which the production and storage of electricity required for the operation of the air handling system for heating and cooling of indoor spaces are ensured. The integrated technological Thermal Active, called Plug&Play, combines passive mitigation strategies such as shadowing and natural ventilation, with an electric heating/cooling system powered entirely by a renewable energy source such as solar radiation. The integrated design of the technological system allows to locate the mechanical components in the outer layer of the roof or floor, ensuring ease of installation, repair, and monitoring.

In addition, the Plug&Play system aims to expand the traditional concept of the floor and roof, from a simple barrier of protection against atmospheric agents to an active device able to produce energy and control indoor comfort. The micro-architecture proposed, thanks to the prefabrication and integration of the components, can be applied in different urban scenarios to ensure simple functionality (e.g., info point, small shops) and to mitigate the overheat produced by the UHI.