Regarding the heat supply of buildings, district heating systems play an important role and are well-established in many countries since they typically enable efficient resource utilization. However, most district heating networks in Europe and worldwide still operate with supply temperatures over 80 to 120°C (medium-high temperature), which is still typically produced by caloric power plants. Currently operating solar district heating (SDH) systems are typically installed with flat-plate collectors providing either heat at lower temperatures or lower efficiency in case of higher temperatures. SHC Task 68 is therefore investigating how to increase the efficiency of SDH systems further and support the dissemination of such systems.