Decarbonisation of Heat Supply of in Single-Family-Dominated Settlements in Vienna

Abstract

Urban decarbonisation strategies increasingly face challenges in low-density residential settlements dominated by single- and two-family houses. These areas are rarely connected to district heating systems and are typically supplied by decentralised fossil gas boilers. This paper analyses the technical, economic and organisational feasibility of renewable heat supply solutions for such settlement structures, using Vienna as a case study. The focus lies on energy spatial analysis as a planning instrument, the economic implications derived from technical system choices, and the feasibility of collective solutions under different ownership and governance conditions. Particular attention is paid to low-temperature heat networks and anergy systems as area-wide infrastructure solutions comparable to district heating, rather than building-by-building approaches. The results show that collective solutions are technically robust and economically viable under specific conditions, notably single ownership structures or public coverage of preparation and transaction costs. The findings provide guidance for scaling renewable heat infrastructure in low-density urban areas.