From kayak clean-ups to rooftop farms and zero-carbon buses, Copenhagen is raising the bar for urban sustainability — both literally and figuratively
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Set beside the still waters of the Sortedams Sø – a large, man-made lake in the heart of Copenhagen – the bench was, in most respects, just like any other. It offered a place to stop and rest while watching joggers and dog walkers file past in the early morning sunshine. But there was one thing about this bench that made it quite unlike any other: it was raised nearly a metre higher than you would expect, and sitting on it involved clambering up.
Thanks to a superb social care system and a strong emphasis on environmental preservation and quality of life, the Danish capital has been declared the world’s happiest city (Happy City Index) as well as the most liveable (Economist Intelligence Unit). However, despite the awards, it’s not all good news for Copenhagen. A recent report by the National Geological Surveys of Denmark and Greenland (GEUS) revealed that over the next 50 years, climate change will likely raise sea levels around the city by between 54 and 74 centimetres. That means that by the latter half of this century, parts of this low-lying coastal city could be consumed by the waves.
The raised bench at Sortedams Sø – and others installed elsewhere in the city in 2022 – were created to alert the public to the dangers of sea-level rise. To reinforce the point, an engraved panel on each bench offers a stark message: ‘Flooding will become part of our everyday life unless we start doing something about our climate. According to the latest UN Climate Report, sea levels are expected to rise by up to one metre by 2100 if global warming continues.’
Copenhagen could be said to have woken up to the dangers of environmental damage as early as 1853, when a cholera outbreak caused by poor wastewater management and the dumping of raw sewage into the harbour killed more than 4,500 people in just a few months. The catastrophe forced the authorities
to rethink how the city’s waste was handled – a focus that continues today. Across the city, neighbourhood collectives and government agencies work to reduce Copenhagen’s contribution to climate change and make it as environmentally friendly as possible.
In fact, the city is aiming to become the world’s first carbon-neutral capital – a goal it’s on course to achieve by the end of this year. This dedication to environmental protection means that alongside its quality-of-life awards, Copenhagen frequently tops sustainability rankings.
As I lowered myself from the bench and continued my morning walk around the lake’s perimeter, I vowed to find out more about how this Scandinavian city had become a global role model for sustainability. Copenhagen is a city sliced through with canals and
waterways. Just like Sortedams Sø, these are a focal point of life, and on a hot summer’s day, they’re filled with swimming, sunbathing locals. At first glance, the water looks clean – but poke about the nooks and crannies along the canal banks and you’ll uncover plastic bags, cups, broken glass bottles and other detritus of urban life.
‘I used to own a kayak rental business,’ said Tobias from Green Kayak, as we paddled through one of the main waterways, filling a bin with rubbish as we went.
‘Being on the water all day – and having the canals as my office – meant I soon realised how much waste was ending up here. One day, I had the idea of offering people a kayak for free if they gathered up some of the rubbish. I’ll admit it’s an unusual business model, but we make money through sponsorships. And I’m proud to say that since we set up in 2017, we’ve gathered more than 100 tonnes of garbage from the city’s waterways. The idea of Green Kayak has spread. We’re now present in cities across Scandinavia, some parts of Germany – even Tokyo. My goal is to take Green Kayak across Europe.’
After a gentle hour of paddling and cleaning, we returned to shore and weighed our haul. ‘Four kilos. We did well. That’s quite a lot in an hour – but it shows how much work is still to be done.’
Kayaking isn’t the only way to get around Copenhagen. Like any major European city, it boasts a comprehensive public transport system – buses, ferries and a metro link all corners of the city. But in Copenhagen, speed and efficiency aren’t the only goals – everything must also serve the environment. The city is the only one in the world where all water-based public transport is electric. By the end of 2025, all buses must be carbon neutral and a new metro line under construction aims to have a 50 per cent lower carbon footprint than its predecessors.
In most cities, personal car use is a major contributor to emissions, but in Copenhagen, the bicycle rules the road. There are estimated to be five times more bicycles than cars and 62 per cent of adults use a bike to commute to work. The city has nearly 400 kilometres of cycle paths (by comparison, London – nearly ten times larger – has just 360 kilometres). Cycle racks are standard on metro carriages, all major roads have adjacent bike lanes, and traffic lights automatically turn green for cyclists travelling faster than 20 km/h – a clever incentive to keep cycling.
The impact on emissions has been enormous, and it’s clear that small changes can make a big difference. Take wildflowers, for example – they’re everywhere. Rather than being neatly trimmed, road verges are allowed to grow wild. The banks of ponds and lakes brim with reeds, pavements are fringed with blooms, and bird, bat and insect boxes are strapped to trees and walls across the city. These features have enabled wildlife – from insects to small mammals – to thrive in the heart of the city.
And you don’t need to travel far to find bigger species. Around a quarter of Copenhagen’s area is green space. Within walking distance of the southern suburbs and airport lies a vast expanse of salt meadows and wetlands where cows, sheep and horses live semi-wild and keep vegetation low, allowing birds – from kites and grebes to kestrels and bitterns – to flourish. At the opposite end of the city, you can step off the metro and minutes later be walking through oak and chestnut woodland among herds of red and fallow deer. But these aren’t wilderness reserves – they’re threaded with cycle paths, walking trails and bird hides so residents can enjoy nature.
As one of northern Europe’s most visited cities, Copenhagen’s sustainability efforts are extended to tourists, too. The CopenPay scheme – launched in 2024 by the city’s tourist board – rewards visitors who make sustainable choices. By collecting rubbish, cycling, walking or using public transport, tourists earn free or discounted entry to attractions, or even a complimentary organic meal.
And how that complimentary meal is produced also matters. Buying locally produced food is important here. Denmark is a world leader in the consumption of organic produce – 14 per cent of all food sales are organic, and 65.5 per cent of Danes buy organic items at least once a week. Across the city are numerous restaurants and markets serving entirely organic meals made from locally sourced products.
To find those ingredients, Copenhagen’s chefs often need only look up. Rooftop gardens, forests and farms dot the city. One afternoon I joined a small group of volunteers tending to crops at ØsterGro, an organic rooftop farm. As we gathered ripe rhubarb and brushed soil from thick carrots, one of the volunteers explained that the farm – the first of its kind in the city – was launched in 2014 to help urbanites reconnect with the soil. Today, 40 members buy into a share of the harvest at the start of each growing season and commit time to nurturing the crops.
‘When I was a child, I lived in the countryside and loved gardening with my parents,’ she said. ‘Now I live in an apartment, I don’t have a garden – but coming here every week reminds me of my childhood. On Tuesdays we have a communal vegetarian lunch made with what we grow. It’s my favourite moment of the week.’
All the small-scale projects I’d seen so far were inspiring – proof that simple, affordable actions can improve quality of life for people and wildlife alike. But the true test of a city’s sustainability is how it’s powered. Much of Copenhagen’s energy comes from renewable sources: wind turbines harness sea breezes and solar panels soak up summer sun. But to truly meet its carbon-neutral goals – and inspire other cities to do the same – Copenhagen did something revolutionary. It turned to skiing.
As I slid – slowly, and with much less grace than the locals – down the 850-metre dry ski slope on the roof of CopenHill, a massive waste-to-energy plant on the edge of the city, it was hard to believe that beneath my skis was a furnace turning rubbish into power.
At the base of the slope, I met Sune Martin Scheibye, head of press at CopenHill. ‘The basic concept,’ he explained, ‘is that we take most of Copenhagen’s household waste and convert it – sustainably and without carbon emissions – into heat energy. Using a centralised, city-wide system, we provide almost free heating to 98 per cent of buildings in Copenhagen. Best of all, other countries – Italy, Germany, even the UK – pay us to take their rubbish. And we get free energy from it.’
As we toured the plant, a massive claw lifted waste into furnaces heated to 1,000°C. ‘We can process 70 tonnes of rubbish an hour,’ said Sune. ‘In 2024, we handled 610,000 tonnes – most of which would have gone to landfill elsewhere in Europe.’ Surely, I asked, burning all that waste must create emissions? ‘It does,’ he admitted, ‘but we have a built-in carbon-capture system. Wastewater from the cooling process is cleaned and recycled, and most other emissions are filtered and turned into vapour.’
A system that turns waste into affordable, low-impact energy seemed like a no-brainer. Why, I wondered, wasn’t this model being adopted across Europe? ‘It comes down to practicalities and economics,’ said Sune. ‘Copenhagen is relatively small, and we’ve built this infrastructure over 50 years. Doing the same in a city like London would be far more complex and expensive.’
And perhaps that’s the sad truth. No matter how hard Copenhagen works to make itself sustainable, it may not be enough. Because unless London, Paris and others commit the time and resources to follow its lead, it may not be long before the raised benches beside Sortedams Sø are no longer raised quite so far above the water.
