Energy loads, CO2 emissions and building stocks: Morphologies, typologies, energy systems and behaviour

Today's existing building stocks are major energy consumers and CO 2 emitters, depending on various factors including urban morphology, architectural archetypes, construction technologies, energy systems, and inhabitant behaviour. A large case study based on 96 000 buildings in Paris, France, is the subject of detailed analysis of the existing residential building stock by comparing some environmental metrics of Paris's urban fabric with thermal energy consumption in buildings. The environmental metrics, such as building shape factor and passive volume (for natural ventilation and daylighting), are functions of urban morphology. This comparison of urban forms and heating energy consumption reveals some impacts of urban morphology and building typology on the energy efficiency in the different zones of Paris. The energy efficiency and CO2 emissions related to heating mode and inhabitant behaviour are separated from those linked to urban form and construction technology. Thus, a balanced view of the complex impacts of morphologies, typologies, energy systems, and inhabitant behaviour on energy loads and CO2 emissions is presented, which allows for the optimization of urban form in terms of density, building configuration, and morphology. Similar large-scale simulations can analyse urban form and the mix of building stock as well as the interaction of increased equipment efficiency, alternative energy mix, and inhabitant behaviour.