The goal of DRAGLOW project is to assess the techno-economic viability of drag reducing agents (DRA) for geothermal multi-source district heating networks. The project investigates the technical and economic contribution of DRA’s to district heating networks and geothermal wells. The DRAGLOW project focuses on the development of technical knowledge and system design tools which should lead to practical usable solutions and instruments for cost-effective geothermal multi-source district heating systems in the built environment.