The transformation towards a low carbon energy system requires municipalities to improve their local building stock. Urban building energy modelling (UBEM) is an emerging tool to support municipalities in shaping the necessary strategies by estimating energy demand with high spatial and temporal resolution. This study proposes a Functional Mockup Interface (FMI)-based UBEM that enables interactive capacities to simulate diverse environmental conditions without reinitialisation. The FMI-based approach allows to couple the building energy simulation EnergyPlus with external models. These capacities were tested on a real-world example in the German city of Wuppertal with urban microclimate data. The results are estimates of sub-hourly energy demand based on the adjacent environmental conditions of each building. In order to ameliorate the applicability, the FMI-based UBEM is further enriched by incorporating an automatic procedure to derive 3D building models, displaying high geometrical fidelity, from city-wide point clouds through the screened Poisson surface reconstruction algorithm. The study area contains 5736 residential buildings. A diverse residential building stock was modelled on the basis of the EU project TABULA. To demonstrate the functionality of the proposed UBEM, a demand response scenario was constructed with microclimate data and heat pumps instead of other heating and hot water systems. The capacity of UBE-FMI to dynamically change parameters (e.g. thermostat setpoint) in the building models can benefit the evaluation of demand response strategies and its potential to shed peak loads. In comparison with reference studies, UBE-FMI produced reasonable estimates of energy demand. The 3D building models and simulation results using “live” weather are visualized by a web-interface, which is implemented with the geospatial 3D framework NASA WorldWind.
