Europe’s biggest heat pump system put into operation in Vienna

In Vienna’s Simmering district, three large heat pumps have been commissioned. They will provide heating for 56,000 households in the Austrian capital, using thermal energy from purified wastewater. The capacity is set to be doubled by 2027.

Heat pumps have become a crucial technology for the future of heating. Vienna aims to become climate-neutral by 2040, and a key step toward achieving the goal is to decarbonize heating. Approximately 40% of carbon dioxide emissions in Austria’s capital and largest city stem from the sector.

The first phase of the construction of a large heat pump system in Vienna has been completed, with three out of the planned six units now operational.

The heat pump system marks a significant milestone on the path to climate neutrality

Vienna’s energy company Wien Energie claims it is the largest green heat pump system in Europe. The project utilizes thermal energy from wastewater in the adjacent Ebswien purification plant. The electricity for the operation of the new facility is obtained from the nearby Freudenau hydroelectric plant on the Danube, so renewable sources account for 100% of the energy needs.

“This heat pump system is a crucial milestone on the path to climate neutrality. The City of Vienna is harnessing all the renewable heat sources available to us. With the first three heat pumps, we can provide district heating to 56,000 households. Our heat pump system is a pioneering project in Europe,” Vienna’s Mayor Michael Ludwig stated.

Upon completion, the capacity of the heat pumps in Simmering will reach 110 megawatts

According to Wien Energie, approximately EUR 70 million was invested in the first phase. The remaining three large heat pumps are scheduled to be added by 2027. They will double the heat pump capacity in Simmering to 110 MW. The system would then be able to supply 112,000 households with climate-neutral heat.

Additionally, a heating network pump with a capacity of 7,500 cubic meters per hour has been built at the Simmering power plant, the utility added.

Vienna’s heating network is one of the largest in Europe, serving 440,000 households and 7,800 larger customers. Wien Energie already has two smaller heat pumps that work on waste heat. The city government has an ambition for the share of households supplied with climate-neutral district heating to hit 56% by 2040.