G4S 2.0 is a new project funded by the Italian Space Agency which aims to perform measurements in the field of Fundamental Physics with the two satellites DORESA (E18) and MILENA (E14) of the Galileo-FOC constellation. Indeed, the orbits of these satellites are characterized by a relatively high eccentricity of about 0.16. After a general introduction to the main objectives of G4S 2.0, the preliminary activities developed at IAPS-INAF in Rome for the measurement of the gravitational redshift, based on the time bias analysis of accurate onboard atomic clocks, will be presented. This measurement will be a test for the validity of the local position invariance, one of the ingredients of Einstein’s principle of equivalence
