A good third of CO2 emissions can be traced back to the building sector. In order to meet the climate targets they have set themselves, politicians have been tightening energy standards for construction for years - but instead of setting a good example, federal buildings of all things are lagging behind when it comes to energy efficiency.
It is a truly mammoth task: by 2045, all buildings in Germany should be climate-neutral. Yes all. Even for private households, this is an almost impossible task. It will be even more difficult to modernize the almost two million heated non-residential buildings nationwide - almost 60 percent of them were built before 1978. After all, office, administration and official buildings make up the second largest proportion of these properties, around 186,000 of which are in public hands. But although their energy efficiency is the responsibility of the federal, state and local governments, the authorities find it difficult to meet the requirements they have set themselves.
Example schools: According to the KfW development bank, around 45.6 billion euros had to be invested last year to renovate the buildings, which are often relatively poorly insulated from an energy point of view. In fact, rural districts, cities and municipalities spent just 9.8 billion euros on this - not even a quarter of the required investment sum. A number of town halls, police or court buildings also do poorly in terms of climate balance. Of the 533 public buildings whose primary energy requirements were determined by the German Environmental Aid (DUH) together with the "Ask the State" initiative in 2020, only 16 met the federal government's climate requirements.
The federal ministries were also queried. Of 15 ministries - including the chancellery - only eight were able to provide concrete information on the technical energy requirements of the building. Three of these were below the limit of 70 kilowatt hours (kWh) per square meter (m²) per year, the target for the energy efficiency of buildings. According to the DUH, all others have an urgent need for renovation with up to 140 kWh/m² per year. The Federal Chancellery is well above the limit of 140 kWh/m² per year - a real "climate killer", as the organization laments. One reason for the poor balance sheet is that the building is equipped with oil heating.
"We've been at a standstill for years," complains Paula Brandmeyer, Deputy Head of Energy and Climate Protection at DUH, in an interview with ntv.de. Something like that is incomprehensible "if you tighten the energy standards for industry and private households at the same time". Brandmeyer considers the promise of Federal Building Minister Klara Geywitz that the climate policy goals of the federal government must "also apply to their own buildings and construction projects" to be a pioneer.
The DUH is particularly critical of the fact that many ministries, but also public administration buildings, indicate their energy consumption with a consumption card. This is based on data that are largely determined by usage behavior - such as heating. "A building can be in poor energy condition and consumption is still low when everyone is working from home," explains Brandmeyer. For years, the DUH has therefore been calling for the mandatory introduction of the requirement certificate, in which the energy requirements of buildings are calculated on the basis of the structural condition. This is the only way to identify where there is a need for action.
The construction union IG BAU has long accused the authorities of delaying the renovation of their own climate-damaging buildings. She is therefore calling for a "climate check" of all 186,000 public buildings, on the basis of which the federal states and local authorities should then draw up a renovation roadmap. The DUH wants the renovation sequence to also be based on the amount of energy required. The "climate killers" should be at the top of the to-do list.
There are already a few bright spots. The Federal Ministry of Justice boasts a photovoltaic system installed in the inner courtyards, which "when there is sufficient sunshine, can supply around 100 office jobs with electricity" and solar collectors on the roof, which replace 16,000 kWh of district heating per year. Nevertheless, questions remain for Brandmeyer elsewhere. For example, why the newest buildings of the Federal Ministry of the Interior and the Ministry of Research have significantly different consumption data from the same year of construction. "Why do people still build so differently against their better judgment?" she asks. "Why aren't there uniform rules for federal buildings?"
The requirements of monument protection are just one answer. Even if uninsulated exterior walls and inefficient building shells have great savings potential, there is a risk of trouble with monument conservationists when it comes to exterior insulation of historic facades or climate-friendly energy supply - for example via visible solar systems. Nevertheless, monument protection and energy efficiency are not mutually exclusive. With a primary energy requirement of just 14.6 kilowatt hours (kWh) per square meter (m²) per year, according to the survey by DUH and "Frag den Staat", the Elbphilharmonie in Hamburg is the most climate-friendly public building in Germany.
