Drivers of district heating's dominance in Sweden's urban areas: A historical perspective

District heating systems are common in the Northern Hemisphere, but their extent and position in heating markets vary. In Sweden, district heating currently supplies more than half of the demand for heating in Swedish buildings, significantly more in urban areas, with most of the district heating systems built between 1970 and 1990, motivated by the possibility of combining heat production with efficient generation of power. This analysis explains why so many district heating systems were built through an analysis of historical policy documents, statistical data, and interviews. The conclusion is that interrelated drivers can explain this expansion. In particular, the energy crises of the 1970s led to concerns about oil dependency. The parallel reduction in oil use and imported fuels also improved air quality. A national referendum in 1980 also began the phase-out of nuclear power, with combined heat and power playing a pivotal role in its replacement. Favourable governmental loans and grants, combined with more coercive regulations and a general sense that building district heating systems was a “sign of the times”, encouraged even smaller and mid-sized cities to build district heating systems. Thus, the foundation was laid to support the strong current position of district heating in Sweden. • District heating development in Sweden 1970–1990. • Explaining Swedish district heating dominance. • History of Swedish heat market transition. • Combined heat and power to replace Swedish nuclear power, a forgotten solution. • Investigating Swedish energy policy measures on national and local level 1970–1990.