Apartment building in Berlin supplies its own heat and power

Der Umbau des Lankwitzer Mehrfamilienhauses setzt neue Maßstäbe im Umgang mit Bestandsgebäuden.

An eight-storey building in Berlin built in the 1950s is being converted into an off-grid building that generates its own heating and electricity from solar energy. The apartment building in the Lankwitz district is being extensively refurbished by the degewo housing association, with work scheduled for completion in spring 2017. The total cost of the project is about €5 million. Project management and consulting company Drees & Sommer has been supporting the project since 2012. In addition to project management, the experts helped degewo develop a suitable indoor climate and energy concept.

At the heart of the project is a combination of modern technologies that is novel for established buildings. These include solar hybrid modules, heat and power storage, highly efficient ventilation, and a building envelope that meets passive house standards. PVT modules are used to maximize harvesting of solar energy. A thermal energy storage facility (eTank) covering area of 700 square meters will ensure that surplus energy is not lost, but stored underground. Heat pumps can then feed this thermal energy back into the building’s central heating system. The House of the Future will also be able to store electricity: A redox-flow battery will store the energy in a liquid electrolyte.

The project is a result of degewo’s goal of turning an established apartment building into an off-grid building for the future, allowing the expertise acquired to be transferred to its property portfolio. Drees & Sommer took responsibility for innovation management and developed an overall strategic concept for the House of the Future on the basis of which a property was selected for refurbishment. The consulting company is also responsible for contract management and for ensuring that schedule, quality and cost targets are met. The remodeling began in January 2016 and is expected to take 15 months.