Sustainable Cities: What They Are and Real Examples

By 2050, the number of people living in cities around the world will multiply to 6 billion. That vast urbanization will bring major sustainability challenges, especially in urban areas themselves.

The truth, though, is that these challenges are already here. Many cities in Latin America today have serious problems with shortages of clean water, electricity supply, pollution, transport, education, health care, housing and employment, among others.

That is the challenge. Cities have to plan and manage their resources and spaces properly in order to maximize the economic and social opportunities open to their residents while minimizing environmental damage. Cities are where the main battle against climate change and poverty will be fought.

Many people may think these challenges are the responsibility of government, local or national — that they are the ones who should solve these problems, since that is what we elect them for. But governments, local and national alike, face many fiscal and political limits on what they can achieve.

Achieving effective solutions or innovations also requires large sums of capital, skills and coordination between different powers. In that sense the private sector cannot stand aside, because it holds the resources needed to drive sustainable projects.

Perhaps the main limitation on achieving sustainable cities, though, is the need for society as a whole to take part and change its consumption preferences and lifestyle. More: sustainable consumption

So the difficulties in achieving sustainable cities — the limits of government, the lack of coordination and resources, and citizen participation — can be overcome if the public sector, the private sector and citizens work together. How cities develop will depend on cooperation between those powers.

Citizens, governments and businesses can promote actions, policies and programs aimed at improving the current model of production and consumption. Government, with determined support or pressure from citizens, can create laws or institutions that drive sustainability. For the private sector, this can also be a major business opportunity, in which companies create value through the efficient use of resources while increasing their profits.

If that cooperation is achieved, sustainable cities call for the large-scale development of new infrastructure alongside the creation of new social and cultural institutions. These are the minimum elements for cities to accommodate millions of people without doing irreparable damage to the environment.

What is a sustainable city? A city is an urban space where many people live, while sustainability means meeting our present needs without compromising the possibilities open to future generations.

Sustainable cities, then, are habitats that provide people with an adequate quality of life while preserving resources so as not to compromise the possibilities open to future generations.

For some, however, the concept is mistaken. They consider cities to be paradigms of unsustainability, because cities depend heavily on the outside world to sustain themselves — meaning there are no self-sustaining cities. A city on its own does not have the resources to maintain itself, still less to preserve them.

Beyond that debate, it is worth knowing that cities are the most efficient places to live thanks to economies of scale. Because of population density, cities have lower transport, housing and public service costs, which saves a great many resources. That idea is the central thesis of the book Triumph of the City. 

In that book its author, Edward Glaeser, also criticizes the false environmentalism that champions residential areas designed as country homes which look ecological but are in fact highly inefficient and have unintended consequences. Dense urban areas are therefore better for achieving sustainability.

Beyond the concept of sustainable cities, what is the importance of a sustainable city?

On one hand, achieving this kind of city will improve the lives of millions of people. Better transport systems will raise people’s productivity and incomes and reduce stress and pollution; greater safety will bring peace of mind and more public space for residents; more jobs will make cities more competitive, more equitable and less poor.

On the other, the urban development of the coming decades will determine the trajectory of greenhouse gas emissions and the depletion of natural resources. Whatever development in cities looks like will be what the world looks like. Whether global warming and other global problems worsen or not will depend on them. More: What causes global warming

The IDB defines smart cities as follows:

A smart, sustainable city is an innovative city that uses information and communication technologies (ICT) and other means to improve decision-making, the efficiency of its operations, the delivery of urban services and its competitiveness. At the same time, it seeks to meet the needs of present and future generations in economic, social and environmental terms. It is also attractive to citizens, entrepreneurs and workers, since it creates a safer space with better services and an innovation environment that encourages creative solutions, generates jobs and reduces inequality. In this way smart cities promote a virtuous cycle that produces not only economic wellbeing and social wellbeing, but also the sustainable use of their resources with a view to raising quality of life over the long term.

 

 

Smart cities have many advantages over traditional ones. They increase the efficiency of government, raise residents’ satisfaction, optimize the allocation of resources, allow greater participation by civil society and produce useful indicators for measuring and comparing public policy.

These cities also use smart infrastructure such as wireless sensors that can analyze data and optimize processes across power lines, water pipes, roads and buildings. In doing so they reduce wasted resources and greenhouse gas production. Such systems have so much potential that The Climate Group believes ICT could cut global emissions by 15% by 2020.

Technology, together with the management and planning of social assets, thus becomes a tool for achieving sustainable development.

Attributes and characteristics of sustainable cities

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So what does a city have to do to be sustainable? There are some milestones that, once reached, would bring a city a little closer to sustainability. Some of these are:

• 100% renewable energy production.
• An interconnected transport system that encourages people to walk or cycle by bicycle and to use public transport.
• Resource conservation: improving the efficient use of water and electrical energy; preserving green spaces and wildlife.
• Green building 
• Smart sensors in public services.
• Water recycling systems
• Urban agriculture

Examples of sustainable cities

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Many cities around the world stand out for their sustainability efforts, green projects and long-term vision. Most of these cities are in developed countries, but several are in developing ones. These are some of the sustainable cities in the world:

 

Copenhagen, Denmark

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Copenhagen is a city with significant recognition for its sustainability efforts. In 2013 it won the Index Award for its ambitious climate change adaptation plans. In 2014 it was awarded by the European Commission for its ability to combine sustainable solutions with growth and a high quality of life.

It is also known for an enormous culture of love for bicycles. There are in fact more bicycles than inhabitants, and only 29% of households own a car.

By 2025 the city aims to be the first carbon-neutral city in the world.

Bristol, United Kingdom

 

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Thanks to the high level of education among its citizens, Bristol is a magnet for green companies and environmental organizations. The city is home to many high-tech companies that are environmentally responsible and innovate to reduce their carbon footprint.

The city has also made significant efforts in new sustainable technologies; it has wind turbines for power generation and a high-tech water treatment plant.

Bristol has also produced award-winning innovations, such as Walkit, a prize-winning app designed to encourage people to leave their cars behind and travel on foot.

Curitiba, Brazil

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Of 17 Latin American cities, Curitiba is the best rated in the Latin American Green City Index.

The city has a long history of environmental planning. As early as 1960 the local government was designing the city’s spaces from a holistic perspective to cope with its rapid population growth. It built green areas and efficient transport options, water recycling and sanitation systems, and it limited the uncontrolled spread of urban areas. City authorities also keep detailed track of how much CO₂ the city’s green spaces absorb and of the city’s total CO₂ emissions.

Melbourne, Australia

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Melbourne has been chosen six times running by The Economist as the world’s most liveable city. It is known for its high scores on liveability, health and culture, and above all for its environmental management and public infrastructure.

 

The city has one of the largest tram networks in the world, more than 240 km long. It also has an extensive network of bicycle routes and wide green spaces — it is known, with reason, as the garden city.PDFs 📃 on sustainable cities:

La ruta hacia las smart cities: migrando de una gestión tradicional a la ciudad inteligente
Ciudad y Sostenibilidad: el mayor reto del siglo XXI
Movilidad urbana sostenible: un reto para las ciudades del siglo XXI
Ciudades Sostenibles
Sustainable Cities: Oxymoron or the Shape of the Future?
The Green City Index
Sustainable cities in Latin America 

 

Sources:

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Dialnet
UN
HBR
VisitCopenhagen
Green Capital
Green City Index
The Economist Intelligence Unit
The Climate Group

According to the World Bank in 2023, 56% of the world’s population lives in urban areas.

Last updated: July 5, 2026