The project global goal is to develop an efficient, robust, and accurate model to simulate e-ECS under the Dymola/Modelica framework based on libraries provided by the Topic Manager. The central focus is placed on the major challenges underlined in the Clean Sky 2 MALET project which include the efficient simulation of the Vapor Compression System (VCS), the VCS heat exchangers, and the electrical components. The project modelling approach is twofold as both physical and surrogate models must be developed and integrated into the Dymola/Modelica framework. The TwinECS specific objectives are summarized as follows: • Development of thermo-fluid models: VCS heat exchangers and their successful integration in assembled VCS models. • Development of electrical models for: motor, power inverter, ATRU, IGBT and MOSFET. • Development of surrogate models of the aforementioned thermo-fluid and electrical components based on data analytics technics. • Simulation of a complete thermo-fluid-electrical VCS model using both the standard and the surrogate models.