Current trends of district heating and cooling in Europe - A review

District heating and cooling systems (DHCS) have been widely recognized as crucial energy systems for the ongoing and future decarbonization process, as well as for improving energy efficiency in the building sector across Europe. The purpose of this article is to provide a comprehensive overview of the current state of DHCS in European countries, with a specific focus on their technical characteristics, market structure, legal frameworks, and policies. Additionally, future trends in DHCS development are presented. The article aims to provide up-to date data on the DHCS in Europe which can serve as a valuable foundation for future development of the district heating and cooling sectors. Moreover, research presented in this paper will be used for the creation of new DHC indicators to further enhance the development of DHC systems.