In pursuit of sustainability’s holy grail: climate-positive development

The 583-acre Stockholm Royal Seaport redevelopment (above, seen from the north) follows the coastline of the Lilla Värtan strait, stretching southward beyond the ferry terminals. (Image: Flickr / Norra Djurgårdsstaden)

Stockholm’s Royal Seaport district seeks to go beyond carbon-neutral and actually remove emissions from the environment. It hasn’t been an easy journey.

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In 2009, Stockholm was planning the redevelopment of its Royal Seaport district — a 583-acre brownfield adjacent to the city core — when the city’s mayor at the time, Sten Nordin, realized he had a unique opportunity. The C40 Cities organization, in partnership with the Clinton Climate Initiative, had just announced an ambitious program devoted to “climate-positive” development: large-scale projects that would not only eliminate their own carbon emissions, but remove carbon from surrounding areas as well. At Nordin’s urging, Royal Seaport became one of the program’s founding projects, with the hopes of making the district a global showcase for sustainable cities.

A decade later, the C40 program no longer exists, but the climate-positive goal remains painfully urgent. The world’s cities already generate 70 percent of global CO2 emissions, with new urban developments cracking the skyline every day. The Global Alliance for Buildings and Construction, a United Nations-sponsored initiative committed to reducing building industry emissions, estimates that the world’s urban centers will build the equivalent of an entire New York City every 35 days for the foreseeable future.

Climate-positive development requires the thorough re-imagining of traditional development processes. Typical approaches to sustainability — including energy-efficient building design, waste recycling, public transit, and clean energy sources — can help a development approach carbon-neutrality, meaning it removes as much carbon as it emits. But making a climate-positive development entails governments rethinking everything from building codes to mobility to water and waste management; architects designing differently; and developers building differently, too.

The pressures facing the planet call for that type of herculean effort. Yet few cities have the appetite to force all stakeholders — including themselves — out of their well-established development routines in pursuit of this more ambitious goal. Stockholm is the rare exception: following then-Mayor Nordin’s lead, the city declared that the Royal Seaport would be climate-positive by its completion in 2030, with more than 12,000 new residential apartments and 10 million square feet of office and commercial space.

As Stockholm nears the halfway point in a project with no global precedent, those involved point to two main drivers that have kept Royal Seaport on the climate-positive path: strong political will and private-sector buy-in. Amid early pushback to the climate-positive concept from both the development community and the Swedish national government, Stockholm City Hall held firm to its vision. And once that stance was in place, its planners went to new lengths to help developers build to new standards of sustainability. The result is a premier model of urban sustainability — one worthy of study by cities around the world.

“It was important to set the kinds of bold and ambitious targets that we set,” says Christina Salmhofer, the City of Stockholm sustainability strategist who co-authored the Royal Seaport’s climate-positive roadmap. “But it is easy to have a bold vision. It is much more difficult to implement one.”

Located on the banks of the Lilla Vartän strait, northeast of the Royal Palace of Stockholm and across from the bucolic island of Lidingö, Royal Seaport has for most of its history served as the King of Sweden’s private hunting grounds. As industrialization rose in the 19th century, the area was transformed into a bustling seaport; as industry receded into the late 20th century, it became one of the world’s most expansive urban redevelopment brownfields.

Making Royal Seaport climate-positive would represent a transformation every bit as momentous as those that came before it. “We have a saying in Swedish: sometimes we swat the mosquitoes and swallow the camels,” says Maria Lennartsson, a Stockholm-based environmental consultant who has worked closely with Salmhofer on Royal Seaport development. The adage is a caution against focusing on the small details at the expense of the big picture. As Salmhofer and her team set about creating a climate-positive plan for the development, they were forced to size up the camels. “Writing the roadmap really gave us a sense of the magnitude of what we were trying to accomplish.”

To arrive at this roadmap, city officials called upon a multitude of expert groups to help them establish a new set of sustainability standards. “We consulted academics, ecologists, toxicologists, energy and climate experts, architects and engineers to understand just what was possible,” she says. By the time they’d figured out what it would take to make the Royal Seaport carbon positive, they’d essentially rewritten the building code.

Each new building in the area had to attain some 40 new requirements: minimum design standards for exterior green space and interior daylight, onsite renewable energy generation, graywater plumbing to recycle tap water through toilets, restricted parking for vehicles, and strict standards for energy efficiency and air quality, among others. The changes were controversial, and the initial reaction was icy. Developers argued that the proliferation of municipal building regimes would make economies of scale impossible.

“The developers were not amused,” says Salmhofer. “There was lots of discussion. They said, ‘How can you come up with requirements like this? No one has ever built to this standard.’ And we said, ‘Yes, that’s right.’ ”

The issue eventually found its way to the Riksdag, Sweden’s national parliament, which in 2013 passed a law forbidding municipalities from setting sustainable building standards more stringent than the country’s national building code. Stockholm, however, found a loophole in the legislation. “The city owns all the land in the Royal Seaport,” says Salmhofer, “and so we are able to make contractual agreements with developers to achieve the standards we want.”

That didn’t stop one firm, which was planning a large office complex in the Royal Seaport, from pushing back against the new standards. The key sticking point was the Royal Seaport’s mobility plan, which is based upon a “reversed traffic hierarchy” that prioritizes pedestrians and cyclists first, transit commuters second, and private vehicles last. This particular developer tried to bargain for an exemption to build parking spaces for every employee in its complex.

“We just couldn’t agree to it,” says Salmhofer. The phenomenon of induced demand applies to parking space just as it does to road space: if you build lots of parking, it will only encourage more people to drive. City Hall held firm, but at a cost: the company abandoned its Royal Seaport office plans, and the city redesigned the land to include a greater mix of residential units. “The requirements have to be the requirements for all developers,” says Salmhofer.

Stockholm’s development community may not have been enamored of the Royal Seaport’s new sustainability requirements, but that didn’t dampen their eagerness to build. As a waterfront development in an area close to downtown, the Royal Seaport land was the most attractive in the city, and there was robust competition for land allocations. The planning framework set clear parameters: each allocation called for midrise, mixed-use development at a maximum of seven stories and 120 housing units.

But because the city was asking developers to do things they’d never done before, they quickly realized they’d have to help developers fill the gaps in their knowledge and expertise. The city began organizing capacity-building sessions to explain the logic behind the new standards. “Ideally, we try to meet with the developers and their architects before they have made any decisions about building design,” says Lennartsson. “There is so much for them to think about that will impact their plans. And they need to work more closely with their landscapers and builders.”

Those capacity-building sessions uncovered something the city hadn’t considered: that developers would be building with new materials, systems, and components they’d never used before. They started to ask the city things like which photovoltaic panels were top-rate and how best to increase the energy efficiency of HVAC systems. “We didn’t know the answers to those questions,” says Lennartsson. So the city began to organize trade fairs, where clean-technology manufacturers and distributors could pitch their wares to Royal Seaport developers.

“With each development phase, new developers are joining the process, and the questions about why we are doing this, and how they are supposed to meet the standards, start all over again,” says Lennartsson. As a result, after every round of land allocations, the city organizes capacity-building sessions for developers, with trade fairs following later into the design process.

The trade fairs have helped produce some remarkable outcomes, particularly with PVs. Back in 2009, all of Sweden was generating less than 10 megawatts of power from solar panels, and most of it was off-grid. By 2017, the country was generating more than 300 megawatts of solar power, and nearly all of it was grid-connected. The Royal Seaport doesn’t account for all of the growth, but the trade fairs inspired by the project certainly account for the development community’s knowledge of solar power, and its willingness to incorporate PVs into their designs no matter where they build.

A newly-installed green roof generates solar energy, absorbs carbon dioxide from the atmosphere, and can also serve as a relaxed social setting. (Image: Flickr / Norra Djurgårdsstaden)

It’s in the area of waste management, however, where some of the most clever gains are being made. The Royal Seaport’s waste stream contains 30 percent less food waste and packaging waste than the rest of Stockholm, thanks to a couple of fruitful innovations. Every building is connected to an underground vacuum waste system that sorts trash from recyclables. And every kitchen sink features a disposal unit for organic waste, which is collected at the neighboring wastewater treatment plant and turned into biogas used to generate electricity.

It has taken a full decade for Royal Seaport to work out the kinks of its sustainability vision: to set the standards, plan the district, educate stakeholders, build capacity, build apartments, and get the district’s first residents to move in. (Today, only 3,000 of the 12,000 planned residential units have been completed.) But the early returns are promising.

The biggest gains are expected to be made in the area of building energy use, which accounts for the largest share of greenhouse gas emissions. Royal Seaport’s building energy consumption is 40 percent lower than those built to the standards of the national building code, and the development’s green roofs and courtyards combined are the size of six soccer fields. The city believes it can double the energy efficiency of its already high-performing buildings, largely through commitments to Passive House construction standards and geothermal energy.

In terms of mobility, the expectation is that the reversed traffic hierarchy, combined with the increasing adoption of electric vehicles, can reduce transportation emissions by two-thirds. For every residence in the Royal Seaport, developers have provided an average of 2.1 bicycle parking spaces and 0.46 vehicle spaces, reversing the conventional traffic hierarchy.

Even after all those measures are implemented, reaching climate-positivity is still an uphill climb. Royal Seaport’s CO2 emissions per capita will decline from the Stockholm average of 0.87 metric tons to 0.19 metric tons. That’s a tremendous achievement from an already low baseline (by comparison, New York averages 6.1 metric tons and London averages 3.5 metric tons). But it’s not quite carbon-neutral, let alone climate-positive.

For Royal Seaport, taking that final step into climate-positive development comes in the form of carbon credits: systems and innovations whose impact can help reduce carbon emissions in surrounding developments and communities. In the Royal Seaport’s roadmap, its credits come from applying its sustainability requirements to other forthcoming developments elsewhere in Stockholm, also on city-owned land, totaling an additional 7,000 residential dwellings. Once those credits are factored into the equation, the Royal Seaport’s emissions decline from 0.19 to -0.37 metric tons per capita.

In addition to influencing nearby developments, the groundwork laid in the Royal Seaport may yet be adopted by other municipalities in Sweden — and beyond. Philadelphia’s recent experience certainly echoes some of what Stockholm has been through: last year the city successfully lobbied the Pennsylvania state government for permission to enact its own, more stringent building code, one that will result in emissions 30 percent lower than the state code would.

For its part, Stockholm has already established a set of even more ambitious requirements for emissions reductions in the final phases of the Royal Seaport build-out. It’s not yet clear exactly how developers will meet those “progressive” requirements, but the city has faith that advances in clean technology will make it possible — to go with its track record of pushing the climate envelope.

“The Royal Seaport development will take at least 20 years to build out,” says Salmhofer. “The goals we have for reducing emissions tomorrow can’t be the goals for development 20 years from now.”

Philip Preville is a writer based in the Toronto area.

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December 6, 2019