Buildings’ Energy Consumption, Energy Savings Potential and the Availability of Renewable Energy Sources in Urban Spaces

This work has been developed within the research project Cities on Power, co-financed by the Central Europe program. The project was focused on the promotion of renewable energy sources (RES) in urban contexts, involving citizens in finding the best solutions to reduce their energy bills. Starting from this objective, the study was extended to the analysis of energy savings solutions for residential buildings. Municipalities normally adopt a building code and eventually an energy regulation to pilot buildings’ renovations or the construction of new residential buildings. A crucial aspect regards the ability of the Local Authority to promote and encourage private investments for the reduction of the energy use, before the installation of RES. This work, through the analysis of the buildings stock and the evaluation of the energy saving potentials, aims to update and adapt local buildings code, promoting the most appropriated solutions, for each Municipality or, at an higher scale, for a region. This work has been carried out for the Metropolitan City of Torino, for about fifty Municipalities representing approximately a million and a half inhabitants. The analysis was realized for two hundred and forty thousand buildings, using a Geographical Information System, GIS, to manage the database and to implement the calculations. The specific thermal energy use of each residential building has been estimated as a function of the surface to volume ratio and the construction period, knowing the total energy consumption of each Municipality for the residential sector, through the application of specific models. In the urban context, the evaluation of renewable energy sources was focused on solar technologies, as the most diffused in the built environment. To evaluate the solar potential for each rooftop, a Digital Surface Model (DSM) of the metropolitan area and a sky model have been realized. The analysis of the most effective interventions for the renovation of buildings has been carried out with the processing of statistical data (to photograph the socio-economic characteristics of the communities), and the interpolation with qualitative and quantitative information specific for each building. This work highlights the necessity of a good planning process to pilot the attainment of the 2020 European strategy objectives. A GIS software can manage multiple data coming from different sources and it can help to fix realistic municipal targets, to boost renewable energy sources in combination with buildings’ energy efficiency interventions.