High-resolution, spatial thermal energy demand analysis and workflow for a city district

Knowledge about the demand of renewable thermal energy is essential for the integrated planning of sustainable cities. Planners and decision-makers need high-quality and comprehensive data for rapid and decisive action. However, little to no corresponding information is available for the status quo or possible development scenarios. Thus, new methods for urban building energy modelling and simulation with high resolution and accuracy are needed. In this paper, we present the research we conducted on the thermal energy demand of a city district in Graz, Austria. We developed a novel bottom-up, white box, multi-tool workflow for performing large-scale and high-resolution modelling, simulation and analysis of urban buildings in different development scenarios. We calculated the demand for heating, cooling and hot water in full-year dynamic building simulations and assessed the results quantitatively and spatially. Our results in the Scenario 2050 show that despite massive densification of the building stock by 88%, the calculated heat energy demand rises only by 4%; while the cooling demand soars by 432%. All results are available as hourly mean values and annual totals and in easy-to-understand spatial map representations, thus supporting stakeholders to meet the net-zero CO2-equivalent emission targets of Graz.