Flexibility issues related to the development of network infrastructures for the massive integration of variable renewable energies into the electrical system by 2100.

Summary The massive integration of variable renewable energies (VRE) is causing significant changes in the electrical system. Previously developed in a vertical and centralized manner, the system was robust and reliable. However, VRE production is intermittent and unpredictable. Thus, the system needs to be more flexible with new options such as demand side management, storage or shaving of VRF production. However, the potential of EnRV is unevenly distributed in Europe and with high penetration rates of EnRV, electricity exchanges between regions will increase causing congestion in the grid. Thus, flexibility options may not be able to reduce this congestion. To analyze these effects, the work conducted in this thesis uses the long term prospective model POLES (Prospective Outlook on Long-term Energy Systems) coupled with the new power sector module EUTGRID (EUropean - Transmission Grid Investment and Dispatch). This module includes a detailed representation of the European transmission grid with a more realistic flow calculation. In addition, reinforcements are determined according to the congestion costs of each line. This new coupling allows for a dynamic evolution of the transmission network. The role of the transmission network is then analyzed and compared with other flexibility options. The investments in the grid increase strongly with high penetration rates of EnRVs while the flexibility options cannot fully replace the grid. Finally, an exploratory work is conducted with the introduction of generic distribution networks (urban, semi-urban and rural) in EUTGRID. The results show that the reinforcements are slightly shifted with an increase in the use of back-up technologies (i.e. gas power plants) which increases the total emissions.