The role of district heating in the future European energy system

District heating (DH) is often regarded as a sustainable supply of heat - improving energy efficiency and contributing to net zero emission targets. We analyse the expansion potential of DH in several EU Countries from the perspective of the whole energy system, which comprises interconnected heat power and transport sectors under different scenarios of heat demand development. Our results show a strong potential for DH expansion in most of the countries analysed with an overall share of DH increased from 8% to 40%. Among the countries analysed, Germany, Netherlands, UK, France, and Norway showed the most potential as presently, the DH in these Countries is almost non-existent. The role of potential exploitation of waste heat from electrolysers is also evaluated, and the results show a promising expansion with more than 50 TWh of excess heat introduced in the district heating grid with a 4% higher expansion of DH. We ultimately highlight the need for a comprehensive policy and market framework to promote expansion of energy efficient DH system and achieve an affordable decarbonization of the heating sector.