The overall aim of sEEnergies is to quantify and operationalise the potentials for energy efficiency (EE) in buildings, transport and industry, combining this bottom-up knowledge with temporal and spatial analyses to develop an innovative, holistic and research-based EE-modelling approach going beyond current state-of-the-art science based knowledge and methodologies. Because the changes in one energy sector can contribute to impacts in another sector, it is only possible to have a comprehensive assessment and quantification of the EEFP policies impacts if we look at the energy systems from a holistic point of view and take into consideration the synergies between sectors. Therefore bottom-up sectorial approach and grid assessment, together with energy system modelling and spatial analytics is combined in the novel EE modelling approach. To achieve its aim, sEEnergies comprises a combination of in-depth knowledge on the consumption side and in-depth analyses of the energy systems that enables a detailed scientifically based pool of knowledge needed to make EE potentials concrete and operational, and as a resource on its own. Embedded in the applied project methodology is the identification of synergies across the supply chain and towards additional impacts not directly linked to the energy system. This nonenergy impacts can be very important benefits that are often invisible but which sEEnergies aims to operationalise to a larger extent on a sectoral, system and member state level. For each sector we will take as starting point the state-of-the-art including best practices, policies in place and energy and nonenergy impacts of EE, for the EU and for the 28 Member States. In order to maximise the outreach of sEEnergies’ results and the understanding of their importance, an online and user friendly GIS platform will be developed where EE impacts can be geographically visualised.