E.T.COMPACT is aimed at reaching technology readiness level four for three in-space technologies on the domain of solar energy harvesting and green propulsion. The first technology, a thin film 2-terminal tandem CIGS/Perovskite module with efficiency larger than 15% and a power-per-weight ratio larger than 50W/kg, is called to reduce the cost of in-space solar panels. The second technology is a miniaturized (target volume 3U) green-propulsion mobility module device based on an electrodynamic tether. Designed to have tether reel-in/reel-out capability and equipped with a field emission cathode, the mobility module can use the harvested in-space solar energy to produce propulsion (both thrust and drag) without using propellant nor expellant. For the mobility module, and the satellite platform to host it, research on ultralight structures based on 3D printed compliant polymeric techniques is conducted. Besides mass reduction, the goal is to integrate compliance mechanisms for both tether deployment and thin-film solar panel unfolding. The third technology, which combines the experience and knowledge of the consortium on photovoltaic and tether technologies, is a novel bare-photovoltaic tether that uses the metallic tape tether for both electron collection and as the back contact of tandem CIGS/Perovskite modules. It integrates in a single device solar energy harvesting and propellant-less propulsion. Project impact is enhanced by activities on market analysis, unit mass production, and early commercialization, solidly supported by simulation work to assess the use of these technologies in the field of post mission disposal, active debris removal, in-orbit servicing and space tugs.