Largest TSO in Europe, RTE [http://www.rte-france.com/en] has developed the tool from end-to-end for its own purposes. RTE is still Antares’ primary user and keeps on improving and enhancing its capabilities. Antares has first been meant to provide the software basis on which to build the French Generation Adequacy Report. The publication of this report [http://www.rte-france.com/sites/default/files/2014_generation_adequacy_report.pdf] on a regular basis (every two years) is a legal responsibility of RTE. The tool is also proving very efficient in quite different contexts, such as the establishment of the European Ten-Year-Network-Development-Plan (TYNDP) report [https://www.entsoe.eu/major-projects/ten-year-network-development-plan/tyndp-2014/Pages/default.aspx]. Other examples of use on a wide basis are given by European projects like Twenties [http://www.twenties-project.eu/node/1] or E-Highways [http://www.e-highway2050.eu/e-highway2050/], whose highly demanding requirements regarding calculation performances were adequately met by RTE’s software.