Overview: Vienna is certainly one of Europe’s most impressive cities. From its cafes to the palaces, passing by its museums, the city captures the eyes, ears, and hearts of those visiting it. A less apparent aspect of Vienna’s grandeur is its district heating network, a massive system serving half a million customers. In almost 60 years of history, the DH network has experienced many changes and expansions, but nothing similar to the challenge it faces now: decarbonising and becoming efficient for a net-zero future.  

Current DH system: Vienna district heating system supplies heat to more than 460.000 residences and 6.800 tertiary customers, through more than 1.300km of pipelines. It has a maximum capacity of 3.1 GW and supplies 6,000 GWh of heat per year. The DH system amounts to around 30% of the total heat demand in Vienna.

In 2023, the system had a renewable energy share of 19%, where solar, geothermal and ambient heat have been introduced as new renewable energy sources (since 2019), and natural gas generation was reduced from 71% (2013) to 59% (2023).

What work will ENABLE DHC do?: The project will further advance the decarbonisation of the grid by investigating the implementation of geothermal energy, large-scale heat pumps, and other waste-heat sources. The phase out of fossil fuels will be complemented by works to test the system’s robustness against energy price variations, changes in demand, and evolving regulatory frameworks. Wien Energie, the city’s utility operator, expects to invest more than 400 million euros to decarbonise Vienna’s heating.

Partners involved: AIT