Office Buildings
City Hall Freiburg
City of Freiburg in Breisgau
ingenhoven architects, Düsseldorf
24.000 m²
1.500 m²
May 2013 – middle of 2017
When the city hall in Stühlinger, a district of Freiburg, was completed in November 2017, it became the world’s first public net-plus-energy building. It has a gross floor area of 24,000 square meters and provides space for more than 800 employees.
The special thing about the new building is that it can produce more energy than it needs itself. The public administration building covers its own energy needs and can also feed surplus energy into the municipal power grid. The electricity and energy for heating and cooling are generated from renewable sources such as photovoltaics, solar thermal energy, and geothermal energy.
The result is that the primary energy requirement of the new Stühlinger city hall is only 55 kilowatt hours per square meter per year, which corresponds to 40 percent of the primary energy requirement of a comparable office building. Thanks to these and other special features, the Stühlinger city hall plays a pioneering role in energy and sustainability. Drees & Sommer’s engineering experts were responsible for the corresponding energy concept, technical building services, building physics, and façade technology.
In 2018, the building received the German Sustainability Award!
The Stühlinger city hall is one of our Wall of Fame projects. These are projects that we are particularly proud of. They have not only helped our respective clients, but also us as a company.
Why the Stühlinger city hall deserves a place on our Wall of Fame:
- Pioneering role: When the building was completed in 2017, it became the world’s first public net-plus-energy building
- Primary energy requirement: The primary energy requirement is only 55 kilowatt hours per square meter per year, which corresponds to 40 percent of that of a comparable office building
- German Sustainability Award: In 2018, the Stühlinger city hall received the German Sustainability Award
“We are very proud that our work has made a significant contribution to the success of the project and therefore also to the sustainability award. Holistic and innovative energy and sustainability concepts can only be achieved if everyone works closely together.”
Prof. Michael Bauer, Partner at Drees & Sommer
Added Value
Thanks to holistic planning and advice, the client received a building that is ecological and saves money
Individual services
- General planning
- Building services engineering
- Energy design
- Building physics
- Energy management
- Facade technology
- Project supervision KG 400




