Vienna is building Europe's largest green heat pump system and aims to become climate neutral by 2040. The scheme, which uses heat from wastewater at the Ebswien purification plant and electricity from the Freudenau hydroelectric power plant, is a pioneering initiative in Europe. The first phase of the project, which will cost around €70 million, will provide district heating to 56,000 homes. The three remaining large heat pumps are expected to double the system capacity by 2027, providing climate-neutral heating to 112,000 homes. Vienna's heating network is one of the largest in Europe.