The Building Energy Act has squandered trust in climate policy. The Climate Protection Program leaves open how the targeted emissions reduction in the building sector is to be achieved. The Building Modernization Act can regain trust – but only if the federal government does not treat heating exclusively as a private matter. As much as the sudden introduction of the former 65% rule overwhelmed people, the focus must now be on socially-sensitive action – and not merely on delegating responsibility to private actors.
Eco-friendly living and heating must not be a project for the elite. Climate protection is a collective responsibility. Its greatest asset is social acceptance.
A paradigm shift is needed: We should enable climate protection rather than impose it. This can be achieved, for example, through neighborhood-based approaches, affordable energy, acceptance of different pathways, smart funding corridors and clever combinations of various instruments. There is simply no single solution that works equally well for all people and all situations. And of course, there will be difficult scenarios: for example, buildings that are hard to retrofit, or areas where only blended green gases can bring progress in climate protection. What matters is the overall result.
Neighborhood-based approaches are more promising than solutions for individual buildings. In older buildings, for example, technical constraints or simply the costs can make renovating individual buildings difficult. Renovation projects for entire neighborhoods are more cost-effective and environmentally efficient:
Serial renovation increases the renovation rate
The generation, use and storage of renewable energy work better at neighborhood level
Combined heat and power plants, large solar thermal storage systems, large geothermal systems, wastewater heat and large heat pumps are only worthwhile at neighborhood level
Neighborhoods have social power, foster participatory effects, and are the seeds of urban transformation
Our goals are forward-looking, while building codes are stuck in the past. With 3,800 regulations, the building code is unable to keep pace with change. Obstacles must be removed in this regard. Neighborhood initiatives, for example, must not be thwarted by data protection concerns. Shared energy supply within the same residential street must be permitted. Foundations approved under building codes are not necessary for heat pump installation. In Poland, for example, thick plastic mats suffice. In Japan, officially tested foundations make sense due to the risk of earthquakes and the common use of timber construction; in Germany, they are not needed.
Climate protection requires not fewer, but more approaches and technologies. Only this openness creates many possibilities. Two examples:
When existing neighborhoods are supplied with district heating, the return temperatures in the pipes are often high – this creates new opportunities for supplying nearby new buildings via heat pumps
If new buildings generate a surplus of PV electricity, this can be used to produce hydrogen for a nearby industrial park
If we are open to considering different energy sources and technologies, different scales (individual buildings and neighborhoods) and system boundaries (new construction and existing stock) together, there is enormous potential to find climate-friendly solutions.
Moderate renovation is more cost-effective and climate-efficient. Our efficiency standards are too stringent. Yet, studies show that a middle ground can be more cost-effective and CO₂-efficient, for example when costs, energy consumption and the CO₂ footprint are assessed over the entire life cycle of a building and its construction materials. Beyond a certain insulation thickness, additional centimeters cost more but yield hardly any further energy or CO₂ savings. A building resource certificate could raise awareness of this.
Socially acceptable renovation is more sustainable, and can be made possible through smarter subsidy policies. Renovation roadmaps allow people to implement measures at their own pace. If a roof is renovated for energy efficiency and a story is added, living space is created and land is saved. CO₂-focused subsidies would be more efficient in this regard than previous subsidy guidelines – and consistent with emissions trading and climate funding. Loans should also be available to people of retirement age. They make up one third of homeowners.
Climate-friendly technologies need support. This includes low purchase and installation costs, low energy prices – whether for heat pumps, district heating or biofuels – and more skilled tradespeople. But, as long as a heat pump (including system integration) is sometimes three times more expensive than a gas boiler, and electricity is three times more expensive than gas, a breakthrough is difficult in spite of subsidies. Heating may be a private matter. But it is up to the government to ensure that the free choice of heating systems, as well as building and renovation standards, actually drives the heating transition forward.
Lamia Messari-Becker is a professor of energy-efficient building technology at the Karlsruhe Institute of Technology.
Opinion pieces reflect the views of their authors and do not necessarily represent those of the editorial team.