Is Efficient Efficient? Or: How to Define Efficient District Heating in a Renewable World?

District heating plays an important role in decarbonizing the heating sector in Europe. Current research often focuses on the decarbonization of heat generation in district heating systems, while the role of network-related technical measures and their effects on overall system efficiency has received less attention. This study therefore provides a detailed assessment of technical options for increasing the efficiency of district heating networks, their economic feasibility, and the barriers to their implementation. Based on this analysis, the study derives and examines efficiency criteria for district heating with regard to their future viability and their integration into regulatory law and funding frameworks.