The project kicked off on October 1: Berlin's Senator for Economics, Energy, and Public Enterprises Franziska Giffey, Spandau District Mayor Frank Bewig, Thomas Stephanblome, CEO GETEC Plattform, and Thomas Braun, General Manager of Siemensstadt Square, jointly gave the green light for one of the capital's most ambitious energy projects.
Together with GETEC and Berliner Wasserbetriebe, Siemens is transforming this invisible resource into a sustainable solution for the future. The goal: to supply the Siemens site with completely CO₂-neutral heating and cooling – with the help of one of Europe's largest wastewater heat exchangers.
A milestone is being created under Nonnendammallee
Directly beneath the historic Nonnendammallee in Berlin-Siemensstadt runs one of the city's most important lifelines - a pressure sewer pipe that transports enormous quantities of wastewater every day. Up to 1,000 liters per second flow here toward the Ruhleben wastewater treatment plant, which is only a few kilometers away.
This is precisely where Siemens comes in: the wastewater is diverted and fed through a specially developed heat exchanger. Four loops, each 1.40 meters in diameter and around 800 meters long, utilize the thermal energy of the wastewater - an innovative contribution to sustainable heat supply directly on site.
In the new energy center, the heat generated is brought up to 55 °C using highly efficient heat pumps and fed into the local heating network. The plant delivers up to 10 megawatts of thermal power - enough to heat around 1,000 modern single-family homes. In summer, the plant also provides cooling. Its output is comparable to the district heating supply for entire towns such as Teltow or Neuruppin.
A neighborhood with many facets
With Siemensstadt Square, Siemens is gradually opening up its 76-hectare industrial site over the next few years to create a future-oriented location in Berlin. In the future, this new urban quarter will not only be a place of production, but also a place to live, work, learn, and conduct research.
The innovative energy concept demonstrates how urban energy supply can be made not only efficient but also climate-friendly. Up to 85% of heating and cooling requirements are covered by wastewater, with the remaining 15% provided by air heat pumps – all powered by 100% green electricity.
A blueprint for urban neighborhoods
"Siemens AG has set itself the goal of becoming carbon neutral by 2030. Buildings play a key role in this, as they are responsible for almost 40 percent of CO₂ emissions worldwide. With Siemensstadt Square, we want to show how climate-friendly energy supply can be achieved in existing and new buildings. The use of wastewater heat is a key lever in this regard: it is cost-effective, locally available, and can be tapped precisely where energy demand is highest. Our supply concept sets a milestone for the large-scale use of this resource – and creates a blueprint for other urban districts," says Thomas Braun, General Manager of Siemensstadt Square.
The construction of Europe's largest wastewater heat exchanger is a prime example of the heat transition in Berlin. The innovative energy concept in Siemensstadt Square shows how entire neighborhoods can be supplied with CO₂-neutral energy. Our goal is a climate-neutral Berlin by 2045. An important lever for this is the cooperation between private companies and the public sector, as we see here. Siemensstadt Square is a Berlin location of the future, combining climate protection, security of supply, and economic strength, and has an impact far beyond Berlin." says Franziska Giffey, Mayor and Senator for Economics, Energy, and Public Enterprises.
Climate protection that makes a difference
Siemensstadt Square is a flagship project - not only for Berlin, but for the energy transition throughout Germany. The site alone saves around 1,700 tons of CO₂ annually - equivalent to the binding capacity of approximately 130 hectares of forest.
The future begins beneath our feet - and Siemensstadt Square makes it visible.