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What Is A Green City?

Once, a successful city was almost always a dirty one. Smokestacks, industry, huge roads, traffic jams, these were the signs of a city on the up. Times change. Now, cities are being thought of as more than just production machines. They’re taking their place at the forefront of the fight against climate change, evolving to be greener, cleaner, and better places to live. 

The concept of the ‘Green City’ is gaining traction. But what is it? Let us explain…

The Concept of Green Cities

A good place to start is by defining the term. There’s no single definition, but let’s start with this: a Green City is one that’s “in balance with nature”, according to one academic. But what does that mean on an urban level? 

For that, let’s look at the organisation C40, a collection of the mayors of over 100 of the world’s leading cities. Their goal is to envision and implement city-based climate action that helps reduce emissions and keep 1.5C alive. 

Green Cities are cities that are enacting climate-focused policies to reduce emissions and fight climate change. We separate the common elements of a Green City into three main categories: mobility, urban planning, and resource management.


Cities tend to be big. And big places generally require big systems for moving people around them. For the past 100 years, we’ve designed our cities to accommodate cars. Green cities are leading the way in moving away from dependence on the automobile. Instead, public transportation, cycling, and of course, our own two feet, are having a comeback. 

To encourage people to choose bikes, trains, and buses over their cars, they have to become more attractive options in comparison. It’s much harder to persuade people to cycle when it involves real danger, dicing with death on busy roads, for example. So improving bike lane provision and road safety is a big part of green city efforts. 

London and other cities have introduced Low Emissions Zones, limiting the number of cars that can travel freely in the city. Similarly, Barcelona has pioneered the creation of superblocks – big zones of blocks where only pedestrians and bikes may enter, taking urban space from the car and giving it to people. Quality of life has increased and retail footfall has increased by 30% in these zones.

Public transport needs to be made convenient and as clean as possible. The Chinese city of Shenzhen has achieved great success in this. It’s managed to transform its fleet so that all 16,000 of its buses are now electric – it also has 22,000 electric taxis! Efforts to improve public transportation must focus on linking all aspects: walking, cycling, e-scooters, buses, trains, and more, to be effective.

Green Urban Planning 

What if instead of struggling to move our citizens around vast spaces in an efficient way, we designed our cities for people, first? One new concept that attempts to provide a framework for this is the 15 Minute City. This is the idea that we should all be able to access most of the places we need to go within a 15-minute walk or bike. 

The concept has taken hold in Paris, with the mayor declaring in 2021 the desire to turn Paris into a 15 minute city. Since her election in 2014, Mayor Anne Hidalgo has embarked on a series of projects to make Paris Europe’s greenest city. This has included closing the city’s famous ‘quois’ – roads running align the Sienne – to cars. They’re planning to plant ‘urban forests’ alongside many of the city’s most famous landmarks. And now, plans are going ahead to greenify the Champs-Elysees, the city’s famous traffic-heavy promenade. 

Down to the individual building level, Green Cities must encourage sustainable building practices, both past, and present. For existing buildings that means retrofitting to improve energy efficiency and installing solar panels. For new buildings, regulations must be created to ensure that new construction uses more sustainable materials, that they’re built to last, and that they’re energy-efficient. 

Resource Management

Cities are massive consumers of resources. Keeping their huge populations alive, healthy, and entertained isn’t easy. Cities of the past have often been very damaging to their environment, extracting more and more until their resources are depleted and they have to look further afield to survive. In a Green City, efforts must be made to redress this. 

That means any resources the city uses: energy, water, food, fashion, for example, should be sourced sustainably. Waste and emissions should be limited as much as possible by cleaner systems, more recycling, and less waste. 

Last year, Milan scooped the Earthshot Prize (a new programme awarding the world’s most sustainable projects), for its city-wide food waste programme, the first of its kind. The scheme recovers food from supermarkets, restaurants, and company canteens and distributes it to those in need. Three food hubs recover about 350kg of food per day. At the same time, they’re also working to cut emissions in school dinners by introducing more plant-based meals. So far they’ve cut 20% of their school dinner emissions. 

When it comes to food provision, urban farming has an important role to play. Urban farms, rooftop vegetable patches, and community gardens, can all help provide public good by offering employment, leisure opportunities, and of course, sustainable food. However, for big cities, there will rarely be enough suitable space within the city limits to support itself. Cities can, however, think regionally, rather than sourcing most of their food from all over the world and nearby farms supplying food to the global markets, more food should be made available in the region, where shorter supply chains may decrease emissions. 

Zero Waste

There are many ways for a city to progress towards becoming a ‘Green City’. As the source of over 60% of the world’s emissions, cities can make an astounding difference. That’s why it’s the theme of Zero Waste Festival Berlin this year. If you’ve got an idea, project or solution you’d like to share with us, apply to be part of the festival.