Fostering the energy transition in a neighbourhood perspective: towards Positive Energy Districts’ application for a university case study

The European SET Plan Action 3.2 promotes the deployment and replication of 100 Positive Energy Neighbourhoods by 2025, disclosing the urgent need for adopting an integrated approach able to implement consistent actions aimed at sustainability. The aim of the paper is to investigate, in this framework, a mediterranean non-residential urban district: it analyses whether it could reach Positive Energy District (PED) targets by promoting energy efficiency actions, enhancing its environmental performances. This considering the environmental impact for a system of renovation actions and the goal of providing a benchmarking criterion for PED performances evaluation. Energy models were performed and simulated in non-steady state conditions for assessing their current energy performances; the validation process was followed by the assessment of selected retrofit scenarios and the implementation of Life Cycle Assessment studies. This to evaluate the feasibility of achieving PED level for a redesigned scenario. Results include the validation of the modelled district and an assessment of its renovation potentialities: they reveal that post-renovation configurations for on-site energy generation could provide up to 80 % of district’s annual energy demand. Notwithstanding, the reduction in annual energy demand for the renovated configuration (assessed in the 40 %), is not sufficient to reach PED standards. The LCA approach highlighted that holistic solutions for PED design are required, even stressing that climate neutrality definition does not always imply energy neutrality (or positive energy) and vice versa: the renovated district allowed for a reduction of 63 % life cycle energy compared to only 34 % reduction of global warming potential.