The consumption of energy is expected to increase by 2030 and 2050 (according to baseline projections incorporating current trends) due to two combined factors. On one hand, the population growth anticipated during this period will result in an increase in energy consumption and demand.. On the other hand, daily and seasonal peaks in electricity demand will intensify with the development and diversification of urban needs (especially in the transport and housing sectors). These combined effects cannot be cross analysed with the current general assessments of the environmental impacts of consumption in energy. These general assessments, which are completed every few years, are based on a calculation of the gross volume of energy produced that are not related to an anticipation of the variations in energy demand. This calls for a change in the analytical framework of urban systems in order to enable a cross analysis of urban structures on medium and long term and their impacts in peak demand. The project SUD (Dynamic Urban Systems) aims to lift these scientific and operational barriers, and will develop a highly integrated and system-dynamics modeling approach based on the various flows that affect the urban system (transportation, energy in building sector). The SUD model will enable the building of scenarios with a number of clearly defined assumptions and modeling parameters, including social and economical constraints. This will enable there to be an accurate assessment of the actual environmental impacts of technical solutions: in terms of sustainability of urban systems and their capacity to smooth peaks in demand to match supply (for example, dynamic management of energy demand with the development of smart grids, energy storage, etc.).