Decarbonisation and climate neutrality are nowadays key drivers of the global energy transition. In the European district heating sector, the main approaches to reach the policy targets set for 2050 are electrification by using heat pumps and electric boilers, and integration of low-temperature renewable energy and waste heat sources. The integration of low-grade and waste heat sources into district heat ing (DH) networks is crucial for advancing energy efficiency and decarbonization. This usually results in a considerable demand for heat storage, including seasonal ones. There are also issues related to space requirements and coverage of peak loads. In the SET_HEAT Project, replication and standardisation are pivotal to the strategy for achieving large-scale real change. For instance, the project's tasks included the development of a standardised approach and methodology, which resulted in the framework document, Handbook for planning and development of investment projects. The central concept of the SET_HEAT Project is to develop a set of replicable model investment projects. Various technology options have been explored for replicable projects across different regions, focusing on low-temperature district heating technologies such as solar collectors, heat pumps, and thermal storage systems. These technologies, including water and wastewater heat pumps (WSHP), air source heat pumps (ASHP), flat so lar collectors (FSC), and others, are analysed from different perspectives to determine their suitability for different DH systems. A multi-criteria parametric assessment was carried out within the group of preselected technologies. Then, the preselected projects were addressed with detailed prefeasibility studies to identify their complexity and provide district heating companies with guidelines for further development.The article presents methodologies for the selection of low-temperature district heating technologies as well as the use of various IT tools such as TRNSYS, EnergyPLAN for the selection of district heating system configurations in the decarbonization process. In addition, an integrated project assessment software tool was presented, which is one of the effects of the project.