MUSCADE project will focus on three items involved into city sustainable development : energy, city structure, and climate change. These items are closely linked to each others, at both global and local scales : energy is a major source of green gazes anthropogenic emissions, that cause global climate warming ; and this global warming is reinforced at local scale by urban heat island creation, due to city morphology and expansion.

Given world Kyoto protocol, EU’s climate change package, and French “Grenelle de l’environnement”, urban planners are faced to concretes questions :
- what will be the microclimate in a growing city ?
- What will be the energy demand to ensure resident thermal comfort ?
- What will be CO2 emissions ?
- How to define renewable energies decentralized production patterns?
- How to adapt the urban structure to climate change ?

This project aims to study Paris urban area, and consider the XXIst century time scale, taking into account urban structure modification inertia and climate change timescale. A numerical modelling framework will be used to study key urban processes and their interactions, at building scale, block scale, and city scale. Models will be driven by coupled scenarios including climate change, socio-economic, land-use, building materials as well as local and renewable energies potential.

NEDUM model, from CIRED, will simulate urban expansion for an ideal and simplified city. As the model is driven by socioeconomic mechanisms, still valid on the very long term, NEDUM is well suitable for 2100 projections – whereas other detailed models, like TRANUS, apply for short or medium term projections. Within MUSCADE project, a 2D version will be developed to include spatial density of activities and then more closely represent a real city. ESO will perform an analysis of Paris’s past expansion in order to validate the 2D model.

A zonal model will be used for parametric building energy simulation. Integrated into SALOME framework by CSTB, this model, including thermal gains, losses and exchanges, will allow to study various buildings configurations. At the block level, SIG MORPHOLOGIC modelling framework from LRA-GRECAU will simulate block’s morphology impact on energy parameters as well as interactions between local energy production and microclimate parameters.

TEB model from CNRM will then be improved with data from building and sector studies. TEB is the GAME urban climate and energy numerical model, and will be used as a framework to integrate all functions developed within this project; it will provide overall answers to urban energy and climate change issues addressed within the MUSCADE project. Major TEB improvements will apply to glazing, green roofs , roads direction, and coupling between microclimate and local energy production. From GIEC climate models, we will develop an innovative method to build urban heat island local structure, in interaction with TEB.

The developed framework will then perform simulations from today to 2100. For each scenario, including projections of Paris’ area expansion, we expect results on buildings global energy demand, potential local energy production, urban microclimate including impacts for resident discomfort, and CO2 emissions. Socioeconomic terms will also be simulated (housing access, transportation cost and duration, productive capital), in order to identify sustainable adaptation strategies for cities to climate change.

This study mainly considers energy related to buildings, representing 44% of total final energy demand, but will also take into account some others parameters, as energy and emissions due to transportation, to state the domain of validity of simulation results.

This project is intended to open new interdisciplinary research areas on sustainable cities and to increase urban planners awareness on energy issues within the city, given the climate change. By identifying leverages, the framework could also help future decisions concerning buildings, local energy production, and urban regulations.