Energy management in public institutional and educational buildings: The case of the school of engineering and architecture in Bologna

•The study analyses the energy demand in a historical public school.•The building belongs to the construction history of modern architecture in Italy.•The analysis focuses on winter seasonal performance by using the Energy Signature Method.•Selected retrofitting options are discussed and analysed.•Energy saving can be achieved by limited and non-invasive interventions.

Energy Efficiency (EE) has become a common target for all buildings: the European Directive 2010/31 specifies that every new building must consume very little fossil energy (Nearly Zero Energy Building) by 2020; this deadline for public buildings is fixed by the end of 2018.However, modify the existing heritage is not easy. This is particularly true for historical public buildings belonging to the cultural heritage, because many energy solutions in the field of renovation are not compatible with historic constructions, which need to preserve authenticity and integrity.The paper discusses this critical issue by using a particular building in Italy: analysis, diagnosis and energy audits have been developed for the case study of the School of Engineering in Bologna, a representative building in the history of modern construction. Results of the microclimate monitoring campaign in different classrooms show how the lack of thermal control, together with poorly insulated envelopes’ components, determine high energy consumption. Selected modifications with a minimum impact have been considered for the energy retrofit. Results show a potential energy saving up to 32%, demonstrating how energy saving in historical buildings may be achieved by means of limited and non-invasive interventions on physical and material processes.