Op-Ed: Helsinki wants to go greener sooner, so the city held a novel competition

A pink and purple light installation on an imposing building in Helsinki, Finland, with people skating in front of it.
A light installation illuminates the Finnish National Theatre during the Helsinki Lux Festival on Jan. 7, 2013.

(Jarno Mela / Lehtikuva via AP

Among the many misleading beliefs about climate change, one in particular has too often gone unchallenged. This is the idea that temperature increases will negatively affect only warmer regions, while making polar climates milder and more pleasant. In fact, extreme weather and rising sea levels in colder countries will far outweigh the benefits of warmer winters.

Northern European cities are well aware of this. According to a 2021 study by the World Economic Forum, nine of the 10 leading countries in the transition to sustainability are in Europe, and almost all of them are at high latitudes. For example, Nordic cities are competing with one another to see which can cut its emissions the most through various measures related to mobility, raw material consumption, and energy production. Copenhagen wants to become the first “carbon-neutral capital” as early as 2025, while Stockholm aims to be fossil fuel-free by 2040.

But the case of Helsinki is perhaps the most interesting. Finland has placed the sustainability imperative alongside its other pillars of postwar national development: a democracy premised on equality for all citizens, an economic culture based on a healthy work-life balance, and cities living in harmony with nature. These attributes have allowed a relatively peripheral and sparsely populated country to excel consistently in rankings of the world’s happiest countries.


Helsinki’s carbon-dioxide emissions declined by 26% between 1990 and 2019, despite significant population growth over the same period. But the city still has a major problem: Indoor heating, which accounts for more than half of local emissions, is heavily dependent on coal because the district heating system pumps excess hot water from coal-fired power plants across the capital.

This reality becomes strikingly visible as one travels outward from Helsinki’s historic city center, and the severe, 20th century residential blocks and the softer lines of more contemporary architecture suddenly give way to power plants of monstrous scale. The most imposing of these, Hanasaari, has a nearly 500-foot-tall chimney that still towers above all other buildings in the capital.

The closure of Helsinki’s coal-burning power plants — scheduled for 2029 — is high on the local political agenda. But while almost everyone agrees on the need to phase out coal, how to transform the city’s colossal district heating system in a sustainable way is far less obvious. Besides the technical hurdles, there are no standard solutions on this scale or best practices from which to draw inspiration.

Fortunately, the formidable obstacles Helsinki faces inspired a “moonshot” of urban innovation. In February 2020, the city’s then-mayor, Jan Vapaavuori, launched the Helsinki Energy Challenge, an international competition to solicit ideas and technical proposals to accelerate its green transition. In just a few months, more than 250 groups submitted entries. Earlier this year, four groups — including one created by the design firm I co-founded and a large team of consultants — were announced as joint winners.

All four winning proposals adopted a patient, systemic approach, and did not promise panaceas or magic wands. Our project proposes channeling the hot water used for Helsinki’s district heating system into huge thermal basins floating in the water off the harbor. These would act as a battery to store energy generated from renewable sources such as wind power — which is notoriously erratic, sometimes inaccessible and at other times available at low or even negative prices — and release it into the system when needed.

Helsinki and its Energy Challenge hold lessons for the rest of the world. The first is that climate efforts must balance competition with collaboration. Vapaavuori’s contest allowed Helsinki to synthesize a diverse array of skills and visions.

Second, we need to devise new ways to seek out innovative ideas. City governments usually work on the basis of best practices, selecting projects and policies with a proven track record. This strategy is supposed to minimize risk and the possible waste of taxpayers’ money. But the urgency of the climate crisis — not to mention the other demographic and social challenges that cities will face in the near future — demands a different, sometimes riskier approach. It was the absence of best practices that spurred a flurry of innovation in Helsinki. By preventing a large body of prior work from constraining our imaginations, we can replicate this creativity elsewhere.


Given that discretion and modesty are often seen as distinctly Finnish traits, Vapaavuori deserves credit for providing a model not only for how to set an innovative goal, but also how to form a novel process to achieve it. More cities will likely need to explore the moonshot approach taken by Helsinki as they seek to pursue bolder climate policies.

Carlo Ratti is director of the Senseable City Lab at MIT and co-founder of the international design and innovation office Carlo Ratti Associati.