Projections of design implications on energy performance of future cities: A case study from Vienna

This paper presents the results of a research project involving a new urban development project in thecity of Vienna. Given the expected long life-cycle of this project, the developers requested scientifically-based information concerning the projected extent of the microclimatic changes in the development areaand their potential ramifications for open urban spaces and the planned buildings´ energy and thermalperformance. To address this inquiry, the first stage of the research involved capturing both the currentstate and future projections of the climatic conditions of the area. As a next step building performancesimulation models were used to evaluate alternative building designs (specifically various surface andlayout design options and degrees of vegetation) in view of their mitigation effectiveness vis-à-vis cli-mate change projections. The simulated implications of the assumed climate change trend suggest thatthe future heating loads will be lower, whereas cooling loads will significantly increase. The results helpproviding qualified estimations of the extent to which certain surface and building design features influ-ence future cooling and heating loads. Furthermore results show the importance of taking microclimaticconditions of the relevant area into account.