Analysis of the energy consumption of the Italian railway building stock

Since buildings are highly energivorous systems, the energy renovation of the current building stock is an important issue to be addressed toward a more sustainable society. For such a reason, today, both the political guidelines and administrative practices are oriented to stimulate the application of energy-saving measures in the building sector, mainly to the residential stock and to public infrastructures. Indeed, public administration should act as an example for private citizens. Specifically, according to the most recent national and international policy plans, two main actions such as reducing the final energy demand of buildings and exploitation of renewable energy sources need to be immediately undertaken. This challenging goal also leads to the need of renovating the building stock of railway stations which has undergone extraordinary development in the past century when no particular attention was paid to energy saving. Compared to other buildings, railway stations are particularly penalized in terms of energy consumption due to their intrinsic features (envelope, window-to-wall ratio, usage and occupancy pattern, etc.). However, the fragmentation in terms of construction typology, size and use of the building heritage owned by railway authority, with particular reference to the Italian one, entails the difficulty of establishing executive intervention plans. In this framework, this research aims to complement the current knowledge by a robust and reliable analysis of the energy consumption of the Italian railway stations. The analysis was conducted by identifying a number of groups of similar stations that were clustered according to real data. Moreover, by the adoption of the Building Information Modelling to Building Energy Modelling (BIM to BEM) approach, a comprehensive building stock analysis was carried out in order to evaluate the “energy footprint” of the identified station typologies. Afterward, a data-driven model was also developed in order to correlate the analysed building characteristics and the climatic conditions with the simulated energy consumption of stations. The Italian case was found a perfect location for this study since its wide range of weather and geographic characteristics, and the large building stock owned by the railway public company. The model provides results that are in good agreement with simulation data which demonstrates the validity of the adopted methodology and its applicability at international context. Furthermore, the model resulted to be a useful tool to support decision-makers in the energy renovation planning and to provide baselines for engineers.