The Bahnstadt neighborhood is a community that decided to cut its dependence on oil and dirty electricity, and demonstrate that a neighborhood can function almost without polluting.
Not with speeches, but with facts: buildings that don’t need heating, clean transportation, solar panels on roofs.
There, living differently is not a luxury, it is a shared custom.
From the heart of Germany to the American Midwest
By: Gabriel E Levy B.
Bahnstadt is a modern neighborhood built in the city of Heidelberg, in southwestern Germany, on the banks of the Neckar River and near the Black Forest.
Heidelberg is known for its university, the oldest in the country, and for being a historical and cultural center.
But in recent years, it has also become an international benchmark for urban sustainability. Bahnstadt was built on former abandoned railway land, and was designed from scratch with a clear goal: to minimize its environmental footprint.
By 2024, this district was home to about 6,500 people. All its buildings were built under the Passivhaus standard, an energy efficiency system that saves up to 80% on heating.
The difference is remarkable: while the average emissions per inhabitant in the city is around 2 tonnes of CO₂ per year, in Bahnstadt the figure is only 0.13.
According to data cited in the report published by TIME Magazine in April 2024, this reduction was achieved without sacrificing quality of life, thanks to integrated, efficient and pedestrian-centred urban planning.
Meanwhile, in Ann Arbor, a medium-sized city in the state of Michigan, United States, Bryant’s neighborhood began its own silent revolution.
Many of its homes, built decades ago, lacked thermal insulation and consumed excess energy.
Some families had to allocate up to a third of their income just to keep the heating on in winter.
Starting in 2021, with the support of community organizations and public funds, a process of profound transformation began: structural improvements, solar panels, geothermal pumps. In less than three years, more than 90% of households managed to drastically reduce their energy bills.
Both experiences, one in Europe, the other in North America, show that it is possible to decarbonise urban life from the most intimate scale: the neighbourhood.
Changing from the small: the power of the neighborhood
Bahnstadt was designed as an urban ecosystem.
It’s not just that the houses are efficient, but that the whole neighborhood is.
The balconies have plants that reduce the heat in summer, the roofs capture solar energy, the streets invite you to walk or ride a bicycle.
Everything is designed so that moving without a car, consuming less energy and producing less waste is not a burden, but an easy choice.
Petra Berschin says it without grandiloquence: «Here sustainable living is not a fad, it is simply what we do.»
In Bryant, the road was more arduous. Most of the neighbors did not have access to the Internet, and technical information on energy efficiency was not available to everyone.
Derrick Miller, director of the Community Action Network, led a door-to-door approach. They listened to each family, explained how new technologies worked, and accompanied the process.
The Mewton family was one of the first to join: with the renovations, they reduced their energy bill to almost zero and became a benchmark for their neighbors.
Rafael Robles, an urban planner based in Chicago, sums it up clearly: «Neighborhoods are the ideal scale for change. Because that is where the link with the neighbor allows the solutions to multiply.»
This vision coincides with that of sociologist Bruno Latour, who in his work Where to Land (2017), argues that climate change is not solved from a global abstraction, but from specific territories where people redefine their way of living. The neighborhood, as a microcosm, becomes the first stage of this change.
Cities that lead by example
Bahnstadt and Bryant are not isolated experiments. They are part of a global movement of cities seeking to achieve carbon neutrality in the coming decades.
In 2014, the Carbon Neutral Cities Alliance (CNCA) was founded, a network that brings together cities that have committed to reducing at least 80% of their emissions by 2050.
By the end of 2024, 22 cities on different continents were already part of this initiative.
One of the ideas that has most influenced these developments is that of the Colombian-French urban planner Carlos Moreno, creator of the concept of the «15-minute city».
According to this proposal, each inhabitant should be able to access their work, school, supermarket and health center within a radius of 15 minutes on foot or by bicycle.
This model has been implemented in urban projects such as Nordhavn, in Copenhagen, and in several areas of Bogotá, promoting more compact, connected and sustainable neighborhoods.
In the Danish city of Sønderborg, the commitment to sustainability took the form of public policy. The Project Zero program has been in place since 2007, with the goal of reducing carbon emissions to zero by 2029.
By 2023, they had already achieved a 66% reduction, thanks to district heating networks, biogas, wind energy and community actions.
As economist Nicholas Stern, author of the influential Stern Review on the Economics of Climate Change (2006), explains, «investing in urban decarbonization is not only an ecological necessity, but an economic and social opportunity.»
Not everything is as easy as it seems
Despite the advances, these models face challenges.
In Bahnstadt, many voices pointed out that the neighborhood could become inaccessible to middle or lower sectors. Green homes have higher costs, and there is a risk that sustainability will become a privilege.
In Bryant, although access was free for families, the project relied on public subsidies and private donations.
Without continuity in funding, the process could stall. In addition, breaking down digital and cultural barriers was not easy: technical terms had to be translated, strategies adapted and trust built from scratch.
Sønderborg also has its limits. Although the infrastructure is ready, the success of the project depends on the whole of Denmark moving towards a 100% renewable energy matrix.
It also requires banks to continue offering affordable credit for families to invest in clean technology.
And there is the challenge of scale. How can these models be replicated in megacities such as Mexico City, Lima or São Paulo?
It is not a matter of copying formulas, but of adapting principles: community participation, accessibility, intelligent planning.
As the academic Jane Jacobs states in Death and Life of Big Cities (1961), «successful cities are those that respect the complexity of everyday life.»
Three paths to a possible future
- BedZED, London (2000-2002): One of the first neighbourhoods designed to be self-sufficient. Their homes produced their own energy, recycled water and reused heat. Although he faced difficulties, he showed that another urbanism was possible.
- Nordhavn, Copenhagen (2024): A new urban development where everything is less than a five-minute walk away. Public spaces, services and clean mobility combine to reduce the carbon footprint without sacrificing comfort.
- Sønderborg, Denmark (since 2007): An entire city that decided to reinvent itself. With clear policies, citizen participation and public-private partnerships, it achieved a large-scale energy transformation.
These examples show that there are several paths to a cleaner future.
Some start from scratch, others regenerate what exists. But they all have something in common: they are born of collective commitment, political will and the desire to live better without destroying the environment.
In conclusion
Carbon-neutral neighbourhoods are a concrete example that it is possible to combat climate change from everyday life. It is not just technology, nor large investments.
It’s community, planning, and vision. Bahnstadt, Bryant, and others like them teach that the home can be the starting point of a new covenant with the planet. And in times when everything seems urgent, returning to the neighbourhood can be the first step towards a fairer and more sustainable future.
References:
- Alter, C. (2024). The Rise of Carbon-Neutral Neighborhoods. TIME. Available in: https://time.com/7200318/the-rise-of-carbon-neutral-neighborhoods
- Latour, B. (2017). Where to land. Taurus Publishing.
- Stern, N. (2006). The Economics of Climate Change: The Stern Review. Cambridge University Press.
- Jacobs, J. (1961). The Death and Life of Great American Cities. Random House.
- Moreno, C. (2020). La ville du quart d’heure. Urbanisme.