Global energy demands are increasing, and various forecast have indicated a continuing growth trend in the future. The increased demand often leads to a more stringent impact on the environment and, consequently, on humankind. To obtain a more efficient energy supply and utility network, analysis should consider improvement in i) efficiency of utility transport, ii) energy efficiency within various energy sectors (intensification), and iii) integration of different sectors. The potential of this last improvement has been only vaguely analysed, considering the business-as-usual approaches. To reveal the potential in the integration of different energy sectors, it is necessary to define the energy needed rather than considering traditional utility levels. Instead of using the top-down approach of first selecting the type and level of utility and only consequently covering the needs from available utilities, using a bottom-up approach can be beneficial. In the latter, the type and level of energy are derived for energy demands in a certain sector for the most common activities, and based on derived energy type and level requirement, the energy supply and utility network can subsequently be constructed. The aim of this study was to decrease overall primary energy source utilisation, while still covering the increasing energy demands. In this study, the types and levels of energy demands were first derived within each sector for the most common activities. The resulting solution based on cross-sector energy integration indicated heat demand reduction of 43 % and 41 % reduction of EU fossil-based GHG emissions in 2016.