This Stockholm Neighborhood Was Built on Ambitious Sustainability Goals. When It Came Up Short, It Doubled Down and Became a Blueprint for Others

The original plan for Hammarby Sjöstad was for an eco-village aimed at attracting the Olympics. They never came, but the locals moved in and, with upgrades, hope to be carbon neutral by 2030

Christa Avampato | Freelance writer

May 5, 2026 10:06 a.m.

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I did not go to Stockholm to study the future of urban design. I went because I wanted to relax in a beautiful city known for its history, art, food and friendly people.

It was early August 2025. I arrived in the Hammarby Sjöstad district fresh from my graduation ceremony at University of Cambridge, where I had just finished my master’s degree in sustainability leadership, not knowing anything about the Hammarby Model.

To the casual observer and tourist like me, Hammarby Sjöstad is a scenic waterfront district. But beneath the timber boardwalk lies a feat of engineering—an invisible machine that transforms waste into energy.

A waiter at a local Vietnamese spot called Madame Thu introduced me to the eco-village, built in phases beginning in the mid-1990s as part of Stockholm’s unsuccessful bid to host the 2004 Summer Olympics.

He gestured to the ski slope visible in the distance—the same one my hotel room overlooked—and dropped a casual bombshell with a wry smile. “You know that ski slope used to be a landfill, right?” he said.

He explained the heat used to make my pho came from waste. The public transit I took to get to the restaurant ran on food scraps from yesterday’s lunch. The beautiful reed beds in the nearby Sickla Canal were engineered filtration systems. There was an invisible, multilayered story underlying every view.

Shortly after I returned to New York, I overheard two college students on the subway speaking Swedish. When I told them I had just visited Hammarby Sjöstad and was blown away by its sustainability, they exchanged knowing glances. “It’s a good start,” one said with a polite smile, “but it could be much better.” They exited at the next stop, leaving me to wonder what they meant. How could it be better? I went looking for answers.

In the early 2000s, global urban planners from Shanghai to London visited Stockholm to study the Hammarby Model. Originally planned to address Stockholm’s housing shortage, the district was transformed into a pioneering experiment in integrated infrastructure to bolster the city’s bid for the Olympics. Planners marveled at the vacuum waste system that sucked trash through underground pipes at up to 40 miles per hour, reducing the need for garbage trucks. They celebrated a closed-loop ecosystem that transformed wastewater into biogas and solid waste into district heating. It was an exemplar for sustainable urban development.

But the design had a flaw: while the hardware was groundbreaking at the time, the project missed its ambitious energy and economic targets. The residents weren’t seeing what developers had promised, because the engineers hadn’t accounted for actual human behaviors or invited the community to participate in decision-making. The Swedish students were right—the system lacked the citizen collaboration required to make the technology work.

In 2011, a small group of concerned, self-empowered citizens led by Allan Larsson—a retired statesman who had served as Sweden’s finance minister—decided to take the reins. They realized that for Hammarby to reach its full potential, residents could no longer be passive consumers; they had to be engaged decision-makers. Around Larsson’s kitchen table, they formed what would become ElectriCITY, focused on providing the community, technology and actionable data needed to change behaviors. They began charting a new course: a citizen-led mission to become climate-neutral by 2030, putting the residents, not the municipality, at the center of Hammarby’s model for change.

Hammarby Sjöstad 1.0’s Olympic dreams

To the outside world, Hammarby Sjöstad looked like a utopia in the early 2000s. In the 1990s, it was a heavily polluted brownfield area—a mix of industrial sites, warehouses and old railway tracks. The revitalization project sought to turn this roughly 600-acre area into a district with a carbon footprint 50 percent lower than the rest of Stockholm.

The urgent mission and vision of Hammarby Sjöstad was the brainchild of Mats Hulth, the Social Democratic mayor of Stockholm in the 1990s, and planner Jan Inghe-Hagström. Seeking to reinvent Stockholm’s image for the new millennium, Hulth and Inghe-Hagström positioned the neighborhood as both an answer to the city’s housing shortage and the crown jewel of its Olympic bid. From the start, planners designed the Olympic Village with a lifespan far beyond the games; once the athletes departed, the high-performance housing would be converted into a permanent residential neighborhood for 25,000 people.

After losing the bid to Athens, Stockholm decided to revitalize the district anyway. In 1997, the city adopted an ambitious environmental program, setting strict targets that were twice as stringent as conventional construction at the time.

The project functioned as a massive public-private partnership. The City of Stockholm, which owned the land, acted as the lead coordinator. It sold plots to private developers on the condition that they follow the Hammarby Model. Funding was a collaborative effort. The city invested roughly 500 million Euros in specialized infrastructure while private developers spent approximately 3 billion Euros on residential and commercial construction.

To manage this, the city utilized a unique eco-governance model. Typically, city departments for water, energy and waste operate independently. In Hammarby, Hulth called for these departments to work together. They assembled integrated project teams with representatives from city departments responsible for planning, roads, real estate, water and waste. For the first time, the output of the waste department—combustible trash—became the input for the energy department in the form of district heating.

The first phase, largely complete by 2014, included several groundbreaking features. Architect Mats Egelius used large glass facades and balconies to maximize the scarce Swedish sunlight and reduce the need for artificial lighting. Silver waste chutes on every street corner connected to a subterranean vacuum system that whisked trash away at high speeds to a central processing plant. The district’s sewage was treated locally to extract biogas, which fueled the city’s public buses and the cooktops in resident kitchens. Open-air canals and green roofs filtered rain and melting snow through the soil before it reached the Baltic Sea.

The global hype vs. the reality check

In its early years, media perception of the district was near-mythic. Global outlets often described it as a miracle on the water. Egelius, the original architect of Hammarby Sjöstad with the firm White Arkitekter, remembers that the international interest was immediate and intense. The delegations were coming from all over the world, he said, to see how they had integrated the technical systems so seamlessly into the urban fabric. It was a design triumph that proved that sustainable could be beautiful.

However, the scientific community offered a more measured perspective. Örjan Svane, a researcher at KTH Royal Institute of Technology, saw the cracks in the model early on. Once residents moved in, technical management was often poor; energy systems were sometimes installed incorrectly or not maintained, and residents didn’t have access to the data they needed to understand their own consumption. The technology was there, but the human management needed to run it effectively was missing.

Maria Xylia, a senior research fellow at the Stockholm Environment Institute, says that while the world watched the hardware, the data told a different story: The energy story of Hammarby Sjöstad 1.0 did not hit the mark. “The reality was that it only achieved about a 30 to 40 percent reduction,” in environmental impact Xylia says, short of the 50 percent goal. “The targets were missed because the design hadn’t accounted for the actual energy use and habits of the people living there.”

To those who say that 30 to 40 percent reduction is good enough, she argues, “The targets need to represent the highest possible ambition, because when targets are watered down, so is the ambition.”

Egelius not only designed Hammarby Sjöstad, he’s lived there for 31 years. His architectural vision was as environmental as it was aesthetic, rooted in the belief that smart design could meet aggressive energy targets. He pioneered the use of floor-to-ceiling glazing to maximize natural light and heat, and he structured the buildings around shared social spaces—like communal launderettes and collective housing—to reduce the district’s overall energy footprint. For Egelius, the architecture was a deliberate tool to move residents away from passive consumption and toward a more collaborative, low-impact lifestyle.

“I design architecture to make people happy,” Egelius explains. “And relationships make people happy. We wanted to create many meeting points in the community to make people see each other and say hello.”

He designed the buildings with mixed housing types—from multi-bedroom apartments to smaller single flats—to ensure diversity and allow residents to size up or down without needing to move and lose their connections and community. Crucially, he incorporated communal spaces such as courtyards and gardens to foster interactions and relationships between neighbors.

“The social aspects are fundamental and need to be included from the very beginning,” says Anna Graaf, White Arkitekter’s sustainability director. “We regularly carry out social impact assessments and initiate various forms of dialogue and co-design processes. We notice that social aspects are increasingly valued financially, both in the short and long term.”

The social side of Hammarby worked beautifully. For example, Egelius’ building has a communal dining space where he and about 40 of his neighbors cook and eat dinner together four times per week. This example of shared lifestyle demonstrates the communal readiness Larsson and his burgeoning ElectriCITY had identified in 2011. A dense social fabric would serve as the foundation for the next phase of the district.

The missed targets were a reality check. The existing technology had done all it could, but a system is only as efficient as the people living inside it. To close the gap, the district needed a new strategy centered on the human factor. In the context of Hammarby 2.0, this meant moving beyond municipal engineering and empowering residents with the data, tools and incentives to manage their own consumption. It required a shift from being passive residents of a green district to becoming active partners in its performance, using their sense of community to drive the behavioral changes that no vacuum tube or biogas plant could achieve on its own.

“Hammarby 1.0 was a masterpiece of Stockholm’s mayor,” Larsson says. “Hammarby 2.0 had to be citizen-led.”

Svane, who studies the district’s governance, uses the Swedish concept of radighet—translated as “agency.”

“The actor can make progress by acting within its own fields of influence,” Svane says. “Identify what can be easily changed quickly and by whom. Figure out who are the real agents of change and give them support.”

The kitchen table cure

Fifteen years ago, looking at his own energy bills, Larsson saw the district’s innovation aging. Energy costs were rising and building systems were underperforming. The technology was there, but the results fell short, costing residents money and leaving the district’s lofty environmental goals out of reach.

So, he did what a storyteller does: he wrote an article in the local newspaper explaining his rising energy bills and asking his neighbors if they saw their bills rising, too. His neighbors confirmed they did, and he invited them to his kitchen table to brainstorm solutions. Through their dialogue, the issues they uncovered were structural. The energy companies provided the power and heat to the district but had no stake in the efficiency of the pipes and wires inside the private buildings; the city had the policy goals but did not own the buildings; and the residents who used energy did not have the data they needed to make changes.

Larsson’s kitchen gathering matched the communal spirit of Egelius’s architectural design. Around Larsson’s table, he and his neighbors planted the seeds of the district’s second act­—ElectriCITY, a citizen-led initiative that would transform the district from Hammarby Sjöstad 1.0’s static model into Hammarby Sjöstad 2.0’s circular economy test bed.

Utilizing Svane’s research and counsel, ElectriCITY realized the agents of change they could influence and support were the housing associations in Hammarby Sjöstad. The housing associations needed energy data in an accessible, actionable format to lower their energy use and costs.

Jörgen Lööf, a business and marketing executive turned community organizer, is the CEO of ElectriCITY. He lived in Hammarby for 15 years and originally got involved as a concerned resident.

“Sustainability goals needed to be financially irresistible to be viable and scalable,” he says. “People will engage with energy issues if it’s fun to solve these problems together.”

Rickard Dahlstrand, chief technology officer of ElectriCITY and a resident of Hammarby, describes a system where residents do not need to think about sustainability. He explains, “People want to live their lives confident that the energy they use to charge the car, wash clothes and heat their homes is being produced in the cleanest, most economical way. The best technology is the kind you don’t see.”

The problem in Hammarby, according to Lööf and Dahlstrand, was the persistence of inaccessible data: the water company did not talk to the electric company, and neither talked to the residents. Under the pair’s leadership, ElectriCITY builds digital tools to break down the data silos. For the first time, housing associations that are members of ElectriCITY could see exactly where and how much energy they used compared to their neighbors. Then, they shared their knowledge and ideas to help one another use less energy and save money. ElectriCITY calls this the “twin transition”—combining sustainability goals with digital transformation.

Going a step further, ElectriCITY leveraged the trust and the relationships it built with the housing associations to guide them to act as a collective to increase their market power. That allowed them to negotiate bulk deals on energy services and products. The results have been so effective that the housing associations have invested 250 million Swedish krona (about $27 million U.S. dollars) into energy retrofits.

A prime example is electric vehicle (EV) charging. Dahlstrand explains that residents plug in their cars when they get home from work—right when the grid is most strained by cooking and lighting.

“It’s the worst time to charge,” Dahlstrand says. “That’s when the energy is dirtiest and most expensive.”

So, ElectriCITY helped install smart EV chargers that talk to each other. Now, residents plug in when they arrive home, but the charging starts in the middle of the night when electricity is clean, inexpensive and abundant.

The new project did not replace the original infrastructure; it optimized it. While the previous era focused on the heavy hardware, such as waste-to-energy plants and vacuum suction tubes, the evolution added a digital layer of sensors and smart controls. For example, ElectriCITY is introducing smart heat pumps and ventilation systems that use A.I. to predict weather patterns and adjust a building’s temperature before the outdoor air even changes. It is also updating the district’s famous vacuum waste system with optical sorting technology, allowing for more precise recycling.

Larsson took the lessons from his kitchen table and scaled them up through Viable Cities, a national Swedish innovation program he helps lead. The result is the Climate City Contract 2030, a nonbinding pact now used by the European Union’s 100 Climate-Neutral Cities Mission to foster investment and digitalization to speed up the transition to carbon neutrality by 2030, influencing broad European efforts for sustainable urban development.

The contract solidifies the relationship between a city, its businesses and its citizens. It acknowledges a municipality cannot solve the climate crisis alone and needs the trust and investment of residents, companies and academia—what ElectriCITY calls the quadruple helix.

Measuring the momentum

Today, Hammarby Sjöstad is no longer just aiming for the original 50 percent reduction, it is pursuing climate neutrality. Specific buildings in the district have already achieved significant measurable gains. Energy use in residential buildings that have undergone the ElectriCITY-led retrofits has dropped by an average of 20 to 30 percent beyond the 1.0 baseline. When combined with the original efficiencies, many of these buildings are now operating at a 60 to 70 percent total reduction in energy use compared to conventional Stockholm housing.

Financially, the model has proven its viability. The 250 million Swedish krona invested by housing associations has not only lowered carbon footprints but also reduced annual energy costs for residents by millions of Swedish krona. On a broader scale, the district is on pace to meet its 2030 carbon-neutral target. This progress is driven by a steady transition to 100 percent renewable energy for the local grid and the rapid expansion of solar-cell coverage on rooftops, which currently provides a growing share of the community’s domestic electricity. By focusing on the quadruple helix, Hammarby is proving that the gap to climate neutrality is best closed through collective investment rather than municipal mandates alone.

New York state of mind

Back home in Brooklyn, I ruminate on three factors Larsson gave me to consider when thinking about how to apply the Hammarby Model in New York.

“First, climate transition is a task for cities,” he says. “Cities cover 3 percent of the Earth but produce 70 percent of emissions.”

Second, 99 percent of a city is already built. “If you’re going to tackle climate emissions, you have to manage the city’s existing buildings,” Larsson says.

Finally, you have to engage citizens and real estate owners. “High energy use is expensive,” he adds. “You can save money by reducing it. You can also save on interest rates by showing you have a well-run association.”

The sustainability argument alone cannot precipitate lasting behavior change. “It’s important to see the economic side of it,” says Larsson. “We have not sold climate or ‘twin transition’ in Hammarby only on climate issues. We have done it because it makes good economic sense.”

Manhattan landlords are currently scrambling to comply with Local Law 97, the city’s groundbreaking legislation to cut building emissions. They are installing heat pumps and upgrading windows, treating the buildings as tunable machines.

But the lesson from Hammarby is you cannot retrofit a city by changing only the hardware. You have to give residents the agency to share, learn and participate in change.

The hardware is important. The software—the people—is what makes it work.

Xylia, the researcher at the Stockholm Environment Institute, now watches the evolution of Hammarby 2.0 from her office within the district. She sees the citizen-led retrofitting of buildings as the necessary completion of the original vision. Her hope is that Hammarby serves as a global laboratory, proving ElectriCITY’s thesis that high-performance technology reaches its potential only when combined with high-performance community engagement.

By giving residents the data and the agency to act, Hammarby Sjöstad is a reminder that we do not just need smarter buildings, we need smarter ways of living together.

Christa Avampato | Read More

Christa Avampato is a freelance writer based in New York City. She writes hopeful stories about this beautiful planet we all share.