Impacts of urban location and climate change upon energy demand of office buildings in Vienna, Austria

Urban heat island effects are already known for decades to result in increased urban outdoor temperatures as compared to the surrounding countryside. At the same time, recent years have witnessed growing concern about climate change's impact upon office buildings' performance in regard to indoor thermal comfort and the energy consumption needed to safeguard this comfort. Thus, it has to be expected that buildings in urban areas are especially effected by increased outdoor temperatures and the effects these may cause for indoor thermal comfort. A vicious circle of raising outdoor temperatures and consequently increasing CO2 emissions associated with raising energy demands for cooling during summer heat waves is anticipated in this respect. This paper builds upon regionally downscaled weather data from future climate scenarios and applies these to dynamic thermal simulation of four sample office buildings in Vienna, Austria, at urban locations ranging from central business district to green outskirts of the city. Values of both heating and cooling demands under current and future conditions are calculated: while heating demands slightly diminish, cooling requirements generally rise significantly. Distinct differences in energy performance of buildings from different periods of construction can be observed. The impact of location within the city is considerable. (C) 2014 Elsevier Ltd. All rights reserved.