With climate change, demographic change, and digitalization, cities are facing numerous challenges. In 2003, Germany underwent an extreme heatwave lasting weeks and causing many deaths. Ever since, devastating floods caused by days of unusually heavy rain and other for the past unusual climate catastrophes became more commonplace due to global warming and it is continuing to increase. Eight percent of German greenhouse gas emissions are released by the construction sector. With the construction of a typical new building, half of the greenhouse gas emissions and energy expenditure that are caused over a life cycle of 50 years are due to the manufacture of the building materials and the construction of the building itself (Source). Therefore, it is the construction sector that carries one of the highest potential environmental savings.
Cities are increasingly implementing climate adaptation interventions – such as green spaces, planted rooftops, light-colored buildings to reflect and not absorb heat, the resurfacing of concrete and tarmac grounds – into their planning and constructing. One of the key measures to mitigating the effects of climate change on the urban environment is water management. Urban wetlands and other permeable surfaces are used to absorb and store water during heavy rainfall to slow down the entry of water into rivers and prevent heavy flooding. Instead of rapid runoff, which causes urban dirt entering surface waters and kills fish when entering lakes and rivers, a more effective use of water via rainwater harvesting (greywater recycling) can be of great use in cities. One way to do so is the Chinese design of a sponge city. Using water-permeable surfaces, such as porous concrete, rooftops planted with mosses or grasses, ponds, ditches and other urban wetlands, like parks and green spaces, a sponge city allows water absorption into the ground where part evaporates and the remainder retains, both to cool the area without the use of fossil energy during hot days. The water does not rush through the sewage system or into rivers and lakes, but slowly seeps into the groundwater where it becomes an excellent source for greywater recycling.
Germany’s capital Berlin is making use of this self-contained system to enable climate regulation and to make the city more resilient and livable in the face of climate change. At the former Berlin Tegel City Airport, a new urban area will be built with approximately 5,000 apartments and several schools, daycare centers, sports facilities and shopping opportunities: the Schumacher-Quartier.
The district, which completion is planned for the mid-2030s, is to become a socially acceptable, diverse, sustainably designed urban living area that is well embedded in the existing neighborhoods. It is intended to both complement the social and public infrastructure and set standards in the area of climate-neutral energy supply. The neighboring Urban Tech Republic, a research and industrial park for urban technologies, with space for up to 1,000 companies with 20,000 employees, will generate renewable energy locally and use it efficiently to protect the climate and water and reduce operating costs.
The alignment and size of the building sites and structures will be designed in such a way that natural air currents and solar radiation create an optimal natural climate with as little technical support as possible. The five square kilometer smart city is planned to be car-free; mobility hubs enable the switch from motorized individual transport to public transport, bike and car sharing as well as e-mobility. The handling of water and raw materials, as well as the use of only non-toxic building materials, are of particular importance: Many retention and infiltration areas are planned both in public spaces and on the buildings. In addition to the visual enhancement, green facades, rooftops and spaces lead to a reduction in air pollution, noise, and local heat effects; they also offer animals refuge and strengthen biodiversity. Furthermore, the implementation of more nature into the city reduces energy consumption, makes a positive contribution to the overall ecological system and increases the quality of life for the residents. Besides sourcing energy from water, a combination of heat and power plants, solar systems and geothermal energy help to create further energy.
With the Schumacher-Quartier, the world’s largest timber construction district will be realized. Wood as a sustainable, regenerative building material enables long-term carbon dioxide storage and reduces the consumption of environmentally harmful materials such as concrete. Functioning as a laboratory for a CO2-neutral city district and new forms of construction, the aim is to be certified according to the criteria of the German Sustainable Building Council.
With the efficient use of energy, sustainable construction, environmentally friendly mobility, clean water recycling, and the use of new materials, the project is considered Berlin’s largest smart city and one of the largest urban development projects in Europe – a real city of the future.
by Marie Klimczak