Challenges in heating demand modelling based on the Kleczków district in Wrocław, Poland

Positive Energy Districts (PEDs) are a cornerstone of the European Union’s climate neutrality agenda, aiming to create urban areas that are energy-efficient, energy-flexible, and capable of producing an annual surplus of renewable energy. This study assesses the potential for establishing a PED in the Kleczków district of Wrocław, Poland, as part of the DigiTwins4PEDs project. A high-resolution 3D LoD2 (Level of Detail) CityGML building model of Kleczków district was generated and the SimStadt energy simulation platform was employed to simulate annual and monthly heating demand. Model performance was evaluated using the simulation-to-measurement ratio for annual heating demand, complemented by the Normalized Mean Bias Error (NMBE) and the Mean Absolute Percentage Error (MAPE). The aggregated district-level simulation-to-measurement ratio was 84.1 %, with an NMBE of − 15.9 %, while the annual building-level MAPE for residential buildings reached 42.4 %. Key challenges included incomplete building attribute data, typology mismatches between German and modern Polish standards, sparse and aggregated consumption data, and limitations in modelling complex non-residential buildings. The study demonstrates that integrating detailed 3D city models with urban energy simulations is a viable approach for PED feasibility analysis and can guide targeted retrofitting, renewable integration, and energy flexibility strategies in diverse European urban contexts. However, robust calibration requires access to localised building-physics parameters and occupancy-usage profiles, without which PED-oriented energy modelling outputs may significantly deviate from real-world performance.