Energy consumption for thermal purposes represents the most impacting energy issue in the European building sector. In addition to space heating, space cooling is constantly growing, due also to climate change, which provokes extreme hot events in summer even in moderate climates. To approach this challenge, it is essential to invest in lowering the overall energy demand, to increase the energy conversion efficiencies and to replace fossil fuels with renewable energy sources. The research here presented deals with the European decarbonization goals and focuses on shallow geothermal technology in district thermal systems (DTS), i.e. Geo-5GDHC. The research investigates whether Geo-5GDHC can be cost-effective in different scenarios based on climatic contexts, insulation levels and the possible integration of photovoltaic and thermal technology (PVT). Through the elaboration of proper KPIs and the implementation and use of a tool specifically developed to couple a Geo-5GDHC energy assessment model with an economic analysis (PILEDHC), the research highlights results and guidelines for providing solutions for new and innovative DTS, considering both energy and economic aspects in different contexts. •District thermal systems are framed in climate change and decarbonization issues.•A new model for simulating Geo-5GDHC network was developed and tested.•Scenarios based on different buildings energy performances and climates were set.•A set of techno-economic KPIs was defined and calculated for the different scenarios.•Results were discussed underlining the role of Geo-5GDHC and further developments.