A methodology for evaluating the potential energy savings of retrofitting residential building stocks

In the European Union (EU), the residential sector is responsible for approximately 40% of the total energy consumption. The existing building stock of member states is inefficient and can and must be retrofitted. This paper describes an innovative approach for the analysis of the potential energy savings of retrofitting existing building stocks. In particular, this study considers the actual technological and economic constraints of the implementation of feasible energy efficiency measures. The analysis was applied to five municipalities in the province of Milan that have signed the Covenant of Mayors, committing to meet and exceed the 20% CO2 reduction objective of the EU by 2020. Because the scale of the analysis is municipal, the resolution of the requested data is high. In order to achieve realistic and achievable energy savings, we realise an energy cadastre and conduct a large in-field survey for each municipality. By detecting the characteristics of the building stock, we are able to know which energy retrofit interventions are feasible from a technical, legal and economic point of view. The result is a tool that does not overestimate the potential energy savings, helping the public administration make energy saving policies.