The project “STADTQUARTIER 2050” already addresses the task of supplying the building stock of the Federal Republic of Germany and thus our cities with almost climate-neutral energy by the year 2050, exemplarily for two quarters in two German cities. The existing ambitious urban energy concept will be implemented in different residential areas under the special aspect of socially acceptable rental price development. More than 960 residential units will be built in the two quarters with a total investment sum of approx. 190 million euros. In detail, this involves a conversion area with conversion, redevelopment and partial demolition and redevelopment of a former hospital area in Stuttgart and a peripheral area redevelopment with expansion of the building area in Überlingen. Since similar tasks in the area of the different residential quarters are pending in both cities, this systematic approach, supported also by the direct exchange in the planned city platform, enables a transfer and use of the results and experiences (i.e. a multiplication effect) from the demonstration quarters not only within the adressed city but also in the respective other city. This approach is supported by the technological and socio-scientific focal points of the work, which are oriented towards the upcoming tasks, as well as by the planned tools. Real tasks are worked on and solved in a transferable way for both cities and thus also for other cities.

Both demonstration quarters aim to design, plan and implement climate-neutral neighbourhood properties in terms of heat and electricity, including the flow of users. The equivalent CO2 emission is used as the assessment parameter for the annual balance sheet. Different boundary conditions have to be taken into account in the neighbourhoods, e.g. a building fabric worthy of preservation in individual buildings, a different owner structure with a high proportion of social housing, partly existing condominium owners’ associations (WEGs), etc.. The focus of the project is on the development of a new residential area for the elderly.

In addition, both cities face the challenge of creating housing for socially disadvantaged population groups as quickly as possible or reducing the bottleneck in affordable rental housing. At the same time, the goal of high-quality energy-efficient renovation must be met. This means that neighbourhoods are to be developed in which living space is to be created, with a climate-neutral building stock at neighbourhood level, an integrated, intergenerational, socially mixed, ecological and climate-neutral residential neighbourhood. And at the same time, it should be affordable living space. Both neighbourhoods are thus concerned with integral planning, cost optimisation, redensification and, ultimately, energy justice, i.e. the redevelopment of neighbourhoods that is neutral in terms of warm rents and socially acceptable, and thus with forward-looking approaches in the sense of climate-neutral supplies.