Urban Energy Simulation Based on a New Data Model Paradigm: the Citygml Application Domain Extension Energy. a Case Study in the Epfl Campus of Lausanne

The rapid urbanisation and the increase of world population underline the need of a new approach in the urban design, based on the energy efficiency and the sustainability of the built environment. When focusing on City Energy Modelling, unlike Building Energy Modelling, each urban simulation engine generally has its own tailor-made data-model: municipalities and other urban information data administrators use their own data base structure to collect and manage urban information data, without the possibility to store and share urban models. To address this issue, since May 2014, an international consortium of urban energy simulation developers and users is establishing an Urban Energy Information standard, as Application Domain Extension (ADE) of the CityGML urban information model. This paper presents a methodology to establish a gateway between one of the urban simulation tools CitySim and the CityGML Energy ADE data format. The future EPFL campus in Lausanne is presented as case study, demonstrating the storage possibility of the CityGML Energy ADE of geometrical properties and annual heating and cooling demands for each building. The connection between CitySim and CityGML Energy ADE represents an innovative approach for the urban energy analysis: city model can be simulated, stored and exchanged between both format creating a common database of knowledge, in which researchers and municipalities could share their results.