Stuttgart University of Applied Sciences and the City of Stuttgart invited to information and dialog
Katja Rade, rector of the University of Applied Sciences, dispensed with welcoming the guests personally, because "time is pressing". This was true, she said, for the challenge of meeting climate change and equally true here and now for the start of a tight program under the motto "Impulses for overcoming current crises", which took around 100 guests through two hours of keynote presentations and subsequent, dialogue-oriented workshops on Thursday (26.1.2023). The focus of this first energy and climate forum was on challenges and solutions for buildings and neighborhoods. Presentations from science and practice underpinned with figures that it will not be easy to achieve the climate targets set at all political levels and by many cities themselves.
The pace of renovation is stagnating and the regionally available sustainable energy potential is not large enough to replace fossil energies. Heat supply in particular is a problem, currently exacerbated by Russia's war against Ukraine. The city of Stuttgart has only 12 years to implement its 2035 climate roadmap. This was adopted by the city parliament last year with the ambitious goal of becoming climate-neutral by then. Jan Kohlmeyer sees the building stock as a key factor here, as he emphasized in his keynote speech. Kohlmeyer is head of the climate protection department of the state capital and is bringing the implementation of Stuttgart's climate targets into the discourse - among other things, by closing ranks with the Stuttgart University of Applied Sciences, which focuses not only on teaching but also on practical solutions for climate change in its research.
There is no "big" solution
Prof. Dr. Bastian Schröter explained that heating networks, which until now have often been fed solely by fossil fuels such as oil and gas, need new sustainable heat sources. However, solar thermal energy, industrial waste heat, geothermal energy, heat pumps and biomass can only be building blocks; there is no "big" solution. In Stuttgart, only 18% of the building stock is connected to district heating. This means that the municipal utilities face an enormous task in expanding the network. Three billion euros have therefore been earmarked for the municipal utility in the 2035 climate roadmap.
Affordable housing versus climate protection: Bleak prospects
Grundstücks- und Wohnungsbaugesellschaft Schwäbisch Hall, represented by technical manager Wolf Gieseke, also faces major challenges. Reducing heating requirements and thus C02 emissions are the focus here. The company plans to invest 300 million euros in this by 2045. And yet, according to Gieseke, the outlook is bleak, because affordable housing and climate protection can hardly be reconciled. Households should spend no more than one-third of their net income on housing. A price limit of a maximum of 16 euros per square meter should ensure that this is possible. However, examples from current refurbishment projects in accordance with KfW40NH (efficiency house level 40with sustainability class) show: "It is not possible to pay less than 19.21 euros minimum rent per square meter. Most families do not come thereby with the income."
Gieseke sees solutions in a reduction of bureaucracy and in the reduction of quality requirements for the ready-made "slab 2.0". And tenants would also have to lower their demands, especially in terms of living space per capita. The question of who should create affordable housing remains. According to Gieseke, this can only be the municipalities or housing companies, because capital investors will always focus on returns.
Just imagine, it's the energy turnaround and everyone is involved in the renovation: Experiences from a participation process in a WEG
Prof. Dr. Stephanie Huber and Prof. Dr. Thomas Bäumer presented a research project on refurbishment projects in condominium owners' associations. This time, however, not from a technical point of view. Instead, the acceptance researchers focus on participatory processes, which are at least as important as innovative technologies for the implementation of climate change projects.
It is curious that the renovation rate in homeowners' associations, at only 0.6%, lags significantly behind the average of one percent in the building stock. Yet there are around ten million WEG condominiums in Germany, or 22% of the total housing stock. Around half of these were built between 1949 and 1978 and are therefore in need of renovation. But the owners can only decide on the building collectively, usually by majority vote, and that makes things so difficult.
Huber and Bäumer developed a model for an ideal process of opinion-forming and decision-making in a WEG. It enables a well-informed group of owners to reach a balanced decision through communication at eye level and was implemented in real life together with a Ludwigsburg WEG.
Fundamental questions were: How do people make decisions? And what motivates them? The spectrum of what motivates people to decide in favor of facade insulation or a PV system on the roof, for example, or to reject such a project, is wide. It ranges from altruistic motivation to make a positive contribution to climate change, to the economic consideration of reducing energy costs, to rejection for lack of money or a general attitude of resistance along the lines of "I don't want to deal with that at all. From the point of view of the researchers, the latter is absolutely understandable, because that is how people are wired. They do not like change.
In the end, the scientifically accompanied participation process in Ludwigsburg led to only the smallest solution of the elaborately worked out redevelopment options that were communicated in a wide variety of ways. But from the feedback of the participants about their satisfaction with the process, the Forscher:innen team sees itself on the right track. The subsequent workshop concluded that caretakers are needed to accompany WEG renovation projects in this way. This also needs political support.
Thinking in terms of neighborhoods, planning local resources individually, reducing living space, redensifying, relaxing building regulations in order to counteract rising construction prices were further ideas. Jan Kohlmeyer's strategy for Stuttgart - phasing out gas and expanding heating networks - is to be supplemented by even more citizen participation. A "Citizens' Council on Climate" has already been decided; it is to start work in March. And, as the workshop concluded, success stories should also be told and best-practice awards presented as an incentive for new innovative and economically interesting projects.
Many visitors deepened their impressions from the program section and the workshops in lively discussions at the subsequent buffet. And a second installment of the Energy and Climate Forum is "absolutely conceivable" for HFT Rector Katja Rade.
Text: Ursula Pietzsch
Photos: Michaela Leipersberger-Linder
