District heating (DH) remains an important part of the energy infrastructure in Central Europe, particularly in urban areas. The region has a relatively well-developed DH sector and therefore a strong basis for a transition towards low-carbon heating. However, the starting conditions differ considerably between countries and systems. With the exception of Austria, many Central European DH systems still obtain approximately 50–95% of their heat from fossil fuels, particularly natural gas and coal. Many networks were also designed for high-temperature operation and are based on ageing technologies and infrastructure.

At the same time, the sector is entering a major transformation phase. EU legislation progressively tightens the criteria for "efficient district heating and cooling", requiring increasing contributions from renewable energy and waste heat on the pathway towards fully decarbonized DH by 2050. Technologies such as large-scale heat pumps, geothermal energy, solar thermal, biomass, industrial and data-centre waste heat, thermal storage and smart low-temperature networks are therefore becoming increasingly important. HEAT 35 is supporting DH systems in central Europe to start the transformation processes and achieve these objectives.