Urban densification and energy performance of existing buildings: a case study

Abstract

Urban densification and preservation of soil are a much discussed topics on which there is still little detailed research. In Switzerland these concepts are also acknowledged by visions and regulations at the federal level together with the importance of increasing energy supply by renewable energy sources and reducing the energy demand in-primis of existing building. The scientific community is however well aware of the need to enlarge the scale of analysis and to move to urban planning and design scales, which would better allow to take into account buildings shape, orientation and density and to detect possible cumulative effects limiting both the access to sunlight or solar gains and the possibility of equipping buildings with solar renewable systems. Moreover the impact of solar energy availability on existing buildings (in particular historical buildings) during urban transformation is still not well understood and is a matter of research. High-urban densification plans expect a complex environment, where self-shading and the overshadows of adjacent buildings can dominate solar energy potential and daylight availability, but also the imposition towards greater energetic production of PV for new buildings would compromise the visual perception of existing settlement under transformation. But how do these urban revolutionary changes towards densification appear and impact? What are the implications for existing buildings during the process? What does solar energy mean for new/existing urban areas with protected heritage buildings? The aim of this research is to delve into these questions by analyzing a real case study in the city of Lugano Paradiso (Ticino). The City Centre district is currently undergoing a profound change towards densification of the urban environment with a new urban master plan and new zoning regulations.